Search results for: Characteristic equation.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1668

Search results for: Characteristic equation.

498 Research on Traditional Rammed Earth Houses in Southern Zhejiang, China: Based on the Theory of Embeddedness

Authors: Han Wu, Jie Wang

Abstract:

Zhejiang’s special geographical environment has created characteristic mountain dwellings with climate adaptability. Among them, the terrain of southern Zhejiang is dominated by mountainous and hilly landforms, and its traditional dwellings have distinctive characteristics. They are often adapted to local conditions and laid out in accordance with the mountains. In order to block the severe winter weather conditions, local traditional building materials such as rammed earth are mostly used. However, with the development of urbanization, traditional villages have undergone large-scale changes, gradually losing their original uniqueness. In order to solve this problem, this paper takes traditional villages around Baishanzu National Park in Zhejiang as an example and selects nine typical villages in Jingning County and Longquan, respectively. Based on field investigations, this paper extracts the environmental adaptability of local traditional rammed earth houses from the perspective of “geographical embeddedness”. And then combined with case analysis, the paper discusses the translation and development of its traditional architectural methods in contemporary rammed earth buildings in southern Zhejiang.

Keywords: Rammed earth building, lighting, ventilation, geographical embeddedness, modernization translation.

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497 Application of the Central-Difference with Half- Sweep Gauss-Seidel Method for Solving First Order Linear Fredholm Integro-Differential Equations

Authors: E. Aruchunan, J. Sulaiman

Abstract:

The objective of this paper is to analyse the application of the Half-Sweep Gauss-Seidel (HSGS) method by using the Half-sweep approximation equation based on central difference (CD) and repeated trapezoidal (RT) formulas to solve linear fredholm integro-differential equations of first order. The formulation and implementation of the Full-Sweep Gauss-Seidel (FSGS) and Half- Sweep Gauss-Seidel (HSGS) methods are also presented. The HSGS method has been shown to rapid compared to the FSGS methods. Some numerical tests were illustrated to show that the HSGS method is superior to the FSGS method.

Keywords: Integro-differential equations, Linear fredholm equations, Finite difference, Quadrature formulas, Half-Sweep iteration.

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496 Evaluation of Carbon Dioxide Pressure through Radial Velocity Difference in Arterial Blood Modeled by Drift Flux Model

Authors: Aicha Rima Cheniti, Hatem Besbes, Joseph Haggege, Christophe Sintes

Abstract:

In this paper, we are interested to determine the carbon dioxide pressure in the arterial blood through radial velocity difference. The blood was modeled as a two phase mixture (an aqueous carbon dioxide solution with carbon dioxide gas) by Drift flux model and the Young-Laplace equation. The distributions of mixture velocities determined from the considered model permitted the calculation of the radial velocity distributions with different values of mean mixture pressure and the calculation of the mean carbon dioxide pressure knowing the mean mixture pressure. The radial velocity distributions are used to deduce a calculation method of the mean mixture pressure through the radial velocity difference between two positions which is measured by ultrasound. The mean carbon dioxide pressure is then deduced from the mean mixture pressure.

Keywords: Mean carbon dioxide pressure, mean mixture pressure, mixture velocity, radial velocity difference.

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495 Atmospheric Fluid Bed Gasification of Different Biomass Fuels

Authors: Martin Lisý, Marek Baláš, Michal Špiláček, Zdeněk Skála

Abstract:

This paper shortly describes various types of biomass and a growing number of facilities utilizing the biomass in the Czech Republic. The considerable part of this paper deals with energy parameters of the most frequently used types of biomass and results of their gasification testing. Sixteen most used "Czech" woody plants and grasses were selected; raw, element and biochemical analyses were performed and basic calorimetric values, ash composition, and ash characteristic temperatures were identified. Later, each biofuel was tested in a fluidized bed gasifier. The essential part of this paper provides results of the gasification of selected biomass types. Operating conditions are described in detail with a focus on individual fuels properties. Gas composition and impurities content are also identified. In terms of operating conditions and gas quality, the essential difference occurred mainly between woody plants and grasses. The woody plants were evaluated as more suitable fuels for fluidized bed gasifiers. Testing results significantly help with a decision-making process regarding suitability of energy plants for growing and with a selection of optimal biomass-treatment technology.

Keywords: Biomass Growing, Biomass Types, Gasification.

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494 A Weighted Group EI Incorporating Role Information for More Representative Group EI Measurement

Authors: Siyu Wang, Anthony Ward

Abstract:

Emotional intelligence (EI) is a well-established personal characteristic. It has been viewed as a critical factor which can influence an individual's academic achievement, ability to work and potential to succeed. When working in a group, EI is fundamentally connected to the group members' interaction and ability to work as a team. The ability of a group member to intelligently perceive and understand own emotions (Intrapersonal EI), to intelligently perceive and understand other members' emotions (Interpersonal EI), and to intelligently perceive and understand emotions between different groups (Cross-boundary EI) can be considered as Group emotional intelligence (Group EI). In this research, a more representative Group EI measurement approach, which incorporates the information of the composition of a group and an individual’s role in that group, is proposed. To demonstrate the claim of being more representative Group EI measurement approach, this study adopts a multi-method research design, involving a combination of both qualitative and quantitative techniques to establish a metric of Group EI. From the results, it can be concluded that by introducing the weight coefficient of each group member on group work into the measurement of Group EI, Group EI will be more representative and more capable of understanding what happens during teamwork than previous approaches.

Keywords: Emotional intelligence, EI, Group EI, multi-method research, teamwork.

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493 Derivation of Fractional Black-Scholes Equations Driven by Fractional G-Brownian Motion and Their Application in European Option Pricing

Authors: Changhong Guo, Shaomei Fang, Yong He

Abstract:

In this paper, fractional Black-Scholes models for the European option pricing were established based on the fractional G-Brownian motion (fGBm), which generalizes the concepts of the classical Brownian motion, fractional Brownian motion and the G-Brownian motion, and that can be used to be a tool for considering the long range dependence and uncertain volatility for the financial markets simultaneously. A generalized fractional Black-Scholes equation (FBSE) was derived by using the Taylor’s series of fractional order and the theory of absence of arbitrage. Finally, some explicit option pricing formulas for the European call option and put option under the FBSE were also solved, which extended the classical option pricing formulas given by F. Black and M. Scholes.

Keywords: European option pricing, fractional Black-Scholes equations, fractional G-Brownian motion, Taylor’s series of fractional order, uncertain volatility.

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492 Superior Performances of the Neural Network on the Masses Lesions Classification through Morphological Lesion Differences

Authors: U. Bottigli, R.Chiarucci, B. Golosio, G.L. Masala, P. Oliva, S.Stumbo, D.Cascio, F. Fauci, M. Glorioso, M. Iacomi, R. Magro, G. Raso

Abstract:

Purpose of this work is to develop an automatic classification system that could be useful for radiologists in the breast cancer investigation. The software has been designed in the framework of the MAGIC-5 collaboration. In an automatic classification system the suspicious regions with high probability to include a lesion are extracted from the image as regions of interest (ROIs). Each ROI is characterized by some features based generally on morphological lesion differences. A study in the space features representation is made and some classifiers are tested to distinguish the pathological regions from the healthy ones. The results provided in terms of sensitivity and specificity will be presented through the ROC (Receiver Operating Characteristic) curves. In particular the best performances are obtained with the Neural Networks in comparison with the K-Nearest Neighbours and the Support Vector Machine: The Radial Basis Function supply the best results with 0.89 ± 0.01 of area under ROC curve but similar results are obtained with the Probabilistic Neural Network and a Multi Layer Perceptron.

Keywords: Neural Networks, K-Nearest Neighbours, Support Vector Machine, Computer Aided Detection

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491 Lean Impact Analysis Assessment Models: Development of a Lean Measurement Structural Model

Authors: Catherine Maware, Olufemi Adetunji

Abstract:

The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment on organizational performance. The model will help industry practitioners to assess the impact of implementing Lean constructs on organizational performance. It will also harmonize the measurement models of Lean performance with the house of Lean that seems to have become the industry standard. The sheer number of measurement models for impact assessment of Lean implementation makes it difficult for new adopters to select an appropriate assessment model or deployment methodology. A literature review is conducted to classify the Lean performance model. Pareto analysis is used to select the Lean constructs for the development of the model. The model is further formalized through the use of Structural Equation Modeling (SEM) in defining the underlying latent structure of a Lean system. An impact assessment measurement model developed can be used to measure Lean performance and can be adopted by different industries.

Keywords: Impact measurement model, lean bundles, lean manufacturing, organizational performance.

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490 Emotion Classification by Incremental Association Language Features

Authors: Jheng-Long Wu, Pei-Chann Chang, Shih-Ling Chang, Liang-Chih Yu, Jui-Feng Yeh, Chin-Sheng Yang

Abstract:

The Major Depressive Disorder has been a burden of medical expense in Taiwan as well as the situation around the world. Major Depressive Disorder can be defined into different categories by previous human activities. According to machine learning, we can classify emotion in correct textual language in advance. It can help medical diagnosis to recognize the variance in Major Depressive Disorder automatically. Association language incremental is the characteristic and relationship that can discovery words in sentence. There is an overlapping-category problem for classification. In this paper, we would like to improve the performance in classification in principle of no overlapping-category problems. We present an approach that to discovery words in sentence and it can find in high frequency in the same time and can-t overlap in each category, called Association Language Features by its Category (ALFC). Experimental results show that ALFC distinguish well in Major Depressive Disorder and have better performance. We also compare the approach with baseline and mutual information that use single words alone or correlation measure.

Keywords: Association language features, Emotion Classification, Overlap-Category Feature, Nature Language Processing.

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489 Contact Temperature of Sliding Surfaces in AISI 316 Austenitic Stainless Steel during Pin on Disk Dry Wear Testing

Authors: Dler Abdullah Ahmed, Zozan Ahmed Mohammed

Abstract:

This study looked into contact surface temperature during a pin-on-disk test. Friction and wear between sliding surfaces raised the temperature differential between contact surface and ambient temperatures Tdiff. Tdiff was significantly influenced by wear test variables. Tdiff rose with the increase of sliding speed and applied load, while dropped with the increase in ambient temperature. The highest Tdiff was 289 °C during the tests at room temperature and 2.5 m/s sliding speed, while the minimum was only 24 °C during the tests at 400 °C and 0.5 m/s. However, the maximum contact temperature Tmax was found during tests conducted at high ambient temperatures. The Tmax was estimated based on the theoretical equation. The comparison of experimental and theoretical Tmax data was revealed good agreement.

Keywords: Pin-on-disk test, contact temperature, wear, sliding surface, friction, ambient temperature.

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488 Numerical Simulation of the Air Pollutants Dispersion Emitted by CHP Using ANSYS CFX

Authors: Oliver Mărunţălu, Gheorghe Lăzăroiu, Elena Elisabeta Manea, Dana Andreya Bondrea, Lăcrămioara Diana Robescu

Abstract:

This paper presents the results obtained by numerical simulation using the software ANSYS CFX-CFD for the air pollutants dispersion in the atmosphere coming from the evacuation of combustion gases resulting from the fuel combustion in an electric thermal power plant. The model uses the Navier-Stokes equation to simulate the dispersion of pollutants in the atmosphere. It is considered as important factors in elaboration of simulation the atmospheric conditions (pressure, temperature, wind speed, wind direction), the exhaust velocity of the combustion gases, chimney height and the obstacles (buildings). Using the air quality monitoring stations it is measured the concentrations of main pollutants (SO2, NOx and PM). The pollutants were monitored over a period of 3 months, after that the average concentration are calculated, which is used by the software. The concentrations are: 8.915 μg/m3 (NOx), 9.587 μg/m3 (SO2) and 42 μg/m3 (PM). A comparison of test data with simulation results demonstrated that CFX was able to describe the dispersion of the pollutant as well the concentration of this pollutants in the atmosphere.

Keywords: Air pollutants, computational fluid dynamics, dispersion, simulation.

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487 Untargeted Small Metabolite Identification from Thermally Treated Tualang Honey

Authors: Lee Suan Chua

Abstract:

This study investigated the effects of thermal treatment on Tualang honey sample in terms of honey colour and heat-induced small metabolites. The heating process was carried out in a temperature controlled water batch at 90oC for 4 hours. The honey samples were put in cylinder tubes with the dimension of 1 cm diameter and 10 cm length for homogenous heat transfer. The results found that the thermal treatment produced not only hydroxylmethylfurfural, but also other harmful substances such as phthalic anhydride and radiolytic byproducts. The degradation of honey protein was due to the detection of free amino acids such as cysteine and phenylalanine in heat-treated honey samples. Sugar dehydration was also occurred because fragmented di-galactose was identified based on the presence of characteristic ions in the mass fragmentation pattern. The honey colour was found getting darker as the heating duration was increased up to 4 hours. Approximately, 60 mm PFund of increment was noticed for the honey colour with the colour change rate of 14.8 mm PFund per hour. Based on the principal component analysis, the score plot clearly shows that the chemical profile of Tualang honey was significantly altered after 2 hours of heating at 90oC.

Keywords: Honey colour, hydroxylmethylfurfural, thermal treatment, Tualang honey.

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486 GenCos- Optimal Bidding Strategy Considering Market Power and Transmission Constraints: A Cournot-based Model

Authors: A. Badri

Abstract:

Restructured electricity markets may provide opportunities for producers to exercise market power maintaining prices in excess of competitive levels. In this paper an oligopolistic market is presented that all Generation Companies (GenCos) bid in a Cournot model. Genetic algorithm (GA) is applied to obtain generation scheduling of each GenCo as well as hourly market clearing prices (MCP). In order to consider network constraints a multiperiod framework is presented to simulate market clearing mechanism in which the behaviors of market participants are modelled through piecewise block curves. A mixed integer linear programming (MILP) is employed to solve the problem. Impacts of market clearing process on participants- characteristic and final market prices are presented. Consequently, a novel multi-objective model is addressed for security constrained optimal bidding strategy of GenCos. The capability of price-maker GenCos to alter MCP is evaluated through introducing an effective-supply curve. In addition, the impact of exercising market power on the variation of market characteristics as well as GenCos scheduling is studied.

Keywords: Optimal bidding strategy, Cournot equilibrium, market power, network constraints, market auction mechanism

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485 Relationships among Tourists’ Needs for Uniqueness, Perceived Authenticity and Behavioral Intentions

Authors: Deniz Karagöz Yüncü

Abstract:

This study tested a structural model which investigates the relationships among tourists’ need for uniqueness, perceived authenticity (object-based authenticity and existential authenticity) and behavioral intentions to consume cultural and heritage destinations. The sample of the study comprised of 281 participants in a cultural heritage site, in Cappadocia, Turkey. The data were provided via face to face interviews in two months (September and October) which considered the high season. Structural equation modeling was employed to test the causal relationships among the hypotheses. Findings revealed tourists’ creative choice had an influence on object-based authenticity and existential authenticity. Tourists’ avoidance had an influence on object-based authenticity. The study concluded that two dimensions, namely, the object based authenticity and existential authenticity had significant impact on behavioral intentions.

Keywords: Needs for uniqueness, object-based authenticity, existential authenticity, behavioral intentions.

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484 On the use of Ionic Liquids for CO2 Capturing

Authors: Emad Ali, Inas Alnashef, Abdelhamid Ajbar, Mohamed HadjKali, Sarwono Mulyono

Abstract:

In this work, ionic liquids (ILs) for CO2 capturing in typical absorption/stripper process are considered. The use of ionic liquids is considered to be cost-effective because it requires less energy for solvent recovery compared to other conventional processes. A mathematical model is developed for the process based on Peng-Robinson (PR) equation of state (EoS) which is validated with experimental data for various solutions involving CO2. The model is utilized to study the sorbent and energy demand for three types of ILs at specific CO2 capturing rates. The energy demand is manifested by the vapor-liquid equilibrium temperature necessary to remove the captured CO2 from the used solvent in the regeneration step. It is found that higher recovery temperature is required for solvents with higher solubility coefficient. For all ILs, the temperature requirement is less than that required by the typical monoethanolamine (MEA) solvent. The effect of the CO2 loading in the sorbent stream on the process performance is also examined.

Keywords: Ionic liquid, CO2 capturing, CO2 solubility, Vaporliquid equilibrium.

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483 Effect of Azespirilium Bacteria in Reducing Nitrogen Fertilizers (Urea) and the Interaction of it with Stereptomyces Sp due the Biological Control on the Wheat (Triticum Asstivum) Sustinibelation Culture

Authors: Omid Alizadeh, Ali Parsaeimehr, Barmak.jaefary Hagheghy

Abstract:

An experiment was conducted in October 2008 due the ability replacement plant associate biofertilizers by chemical fertilizers and the qualifying rate of chemical N fertilizers at the moment of using this biofertilizers and the interaction of this biofertilizer on each other. This field experiment has been done in Persepolis (Throne of Jamshid) and arrange by using factorial with the basis of randomized complete block design, in three replication Azespirilium SP bacteria has been admixed with consistence 108 cfu/g and inoculated with seeds of wheat, The streptomyces SP has been used in amount of 550 gr/ha and concatenated on clay and for the qualifying range of chemical fertilizer 4 level of N chemical fertilizer from the source of urea (N0=0, N1=60, N2=120, N3=180) has been used in this experiment. The results indicated there were Significant differences between levels of Nitrogen fertilizer in the entire characteristic which has been measured in this experiment. The admixed Azespirilium SP showed significant differences between their levels in the characteristics such as No. of fertile ear, No. of grain per ear, grain yield, grain protein percentage, leaf area index and the agronomic fertilizer use efficiency. Due the interaction streptomyses with Azespirilium SP bacteria this actinomycet didn-t show any statistically significant differences between it levels.

Keywords: AzetobacterSP, AzespiriliumSP, StreptomycesSP

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482 Torsional Statics of Circular Nanostructures: Numerical Approach

Authors: M.Z. Islam, C.W. Lim

Abstract:

Based on the standard finite element method, a new finite element method which is known as nonlocal finite element method (NL-FEM) is numerically implemented in this article to study the nonlocal effects for solving 1D nonlocal elastic problem. An Eringen-type nonlocal elastic model is considered. In this model, the constitutive stress-strain law is expressed interms of integral equation which governs the nonlocal material behavior. The new NL-FEM is adopted in such a way that the postulated nonlocal elastic behavior of material is captured by a finite element endowed with a set of (cross-stiffness) element itself by the other elements in mesh. An example with their analytical solutions and the relevant numerical findings for various load and boundary conditions are presented and discussed in details. It is observed from the numerical solutions that the torsional deformation angle decreases with increasing nonlocal nanoscale parameter. It is also noted that the analytical solution fails to capture the nonlocal effect in some cases where numerical solutions handle those situation effectively which prove the reliability and effectiveness of numerical techniques.

Keywords: NL-FEM, nonlocal elasticity, nanoscale, torsion.

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481 Application of Strong Optical Feedback to Enhance the Modulation Bandwidth of Semiconductor Lasers to the Millimeter-Wave Band

Authors: Moustafa Ahmed, Ahmed Bakry, Fumio Koyama

Abstract:

We report on the use of strong external optical feedback to enhance the modulation response of semiconductor lasers over a frequency passband around modulation frequencies higher than 60 GHz. We show that this modulation enhancement is a type of photon-photon resonance (PPR) of oscillating modes in the external cavity formed between the laser and the external reflector. The study is based on a time-delay rate equation model that takes into account both the strong feedback and multiple reflections in the external cavity. We examine the harmonic and intermodulation distortions associated with single and two-tone modulations in the mm-wave band of the resonant modulation. We show that compared with solitary lasers modulated around the carrier-photon resonance frequency, the present mm-wave modulated signal has lower distortions.

Keywords: Distortion, intensity modulation, optical feedback, semiconductor laser.

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480 Torque Ripple Minimization in Switched Reluctance Motor Using Passivity-Based Robust Adaptive Control

Authors: M.M. Namazi, S.M. Saghaiannejad, A. Rashidi

Abstract:

In this paper by using the port-controlled Hamiltonian (PCH) systems theory, a full-order nonlinear controlled model is first developed. Then a nonlinear passivity-based robust adaptive control (PBRAC) of switched reluctance motor in the presence of external disturbances for the purpose of torque ripple reduction and characteristic improvement is presented. The proposed controller design is separated into the inner loop and the outer loop controller. In the inner loop, passivity-based control is employed by using energy shaping techniques to produce the proper switching function. The outer loop control is employed by robust adaptive controller to determine the appropriate Torque command. It can also overcome the inherent nonlinear characteristics of the system and make the whole system robust to uncertainties and bounded disturbances. A 4KW 8/6 SRM with experimental characteristics that takes magnetic saturation into account is modeled, simulation results show that the proposed scheme has good performance and practical application prospects.

Keywords: Switched Reluctance Motor, Port HamiltonianSystem, Passivity-Based Control, Torque Ripple Minimization

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479 Effect of Turbulence Models on Simulated Iced Aircraft Airfoil

Authors: Muhammad Afzal, Cao Yihua, Zhao Ming

Abstract:

The present work describes a computational study of aerodynamic characteristics of GLC305 airfoil clean and with 16.7 min ice shape (rime 212) and 22.5 min ice shape (glaze 944).The performance of turbulence models SA, Kε, Kω Std, and Kω SST model are observed against experimental flow fields at different Mach numbers 0.12, 0.21, 0.28 in a range of Reynolds numbers 3x106, 6x106, and 10.5x106 on clean and iced aircraft airfoil GLC305. Numerical predictions include lift, drag and pitching moment coefficients at different Mach numbers and at different angle of attacks were done. Accuracy of solutions with respect to the effects of turbulence models, variation of Mach number, initial conditions, grid resolution and grid spacing near the wall made the study much sensitive. Navier Stokes equation based computational technique is used. Results are very close to the experimental results. It has seen that SA and SST models are more efficient than Kε and Kω standard in under study problem.

Keywords: Aerodynamics, Airfoil GLC305, Iced Airfoil, Turbulence Model

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478 Solving the Nonlinear Heat Conduction in a Spherical Coordinate with Electrical Simulation

Authors: A. M. Gheitaghy, H. Saffari, G. Q. Zhang

Abstract:

Numerical approach based on the electrical simulation method is proposed to solve a nonlinear transient heat conduction problem with nonlinear boundary for a spherical body. This problem represents a strong nonlinearity in both the governing equation for temperature dependent thermal property and the boundary condition for combined convective and radiative cooling. By analysing the equivalent electrical model using the electrical circuit simulation program HSPICE, transient temperature and heat flux distributions at sphere can be obtained easily and fast. The solutions clearly illustrate the effect of the radiation-conduction parameter Nrc, the Biot number and the linear coefficient of temperature dependent conductivity and heat capacity. On comparing the results with corresponding numerical solutions, the accuracy and efficiency of this computational method is found to be good.

Keywords: Convective boundary, radiative boundary, electrical simulation method, nonlinear heat conduction, spherical coordinate.

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477 Multiple Peaks Tracking Algorithm using Particle Swarm Optimization Incorporated with Artificial Neural Network

Authors: Mei Shan Ngan, Chee Wei Tan

Abstract:

Due to the non-linear characteristics of photovoltaic (PV) array, PV systems typically are equipped with the capability of maximum power point tracking (MPPT) feature. Moreover, in the case of PV array under partially shaded conditions, hotspot problem will occur which could damage the PV cells. Partial shading causes multiple peaks in the P-V characteristic curves. This paper presents a hybrid algorithm of Particle Swarm Optimization (PSO) and Artificial Neural Network (ANN) MPPT algorithm for the detection of global peak among the multiple peaks in order to extract the true maximum energy from PV panel. The PV system consists of PV array, dc-dc boost converter controlled by the proposed MPPT algorithm and a resistive load. The system was simulated using MATLAB/Simulink package. The simulation results show that the proposed algorithm performs well to detect the true global peak power. The results of the simulations are analyzed and discussed.

Keywords: Photovoltaic (PV), Partial Shading, Maximum Power Point Tracking (MPPT), Particle Swarm Optimization (PSO) and Artificial Neural Network (ANN)

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476 Parametric Study of Vertical Diffusion Still for Water Desalination

Authors: A. Seleem, M. Mortada, M. El Morsi, M. Younan

Abstract:

Diffusion stills have been effective in water desalination. The present work represents a model of the distillation process by using vertical single-effect diffusion stills. A semianalytical model has been developed to model the process. A software computer code using Engineering Equation Solver EES software has been developed to solve the equations of the developed model. An experimental setup has been constructed, and used for the validation of the model. The model is also validated against former literature results. The results obtained from the present experimental test rig, and the data from the literature, have been compared with the results of the code to find its best range of validity. In addition, a parametric analysis of the system has been developed using the model to determine the effect of operating conditions on the system's performance. The dominant parameters that affect the productivity of the still are the hot plate temperature that ranges from (55- 90°C) and feed flow rate in range of (0.00694-0.0211 kg/m2-s).

Keywords: Analytical Model, Solar Distillation, Sustainable Water Systems, Vertical Diffusion Still.

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475 Adaptation Learning Speed Control for a High- Performance Induction Motor using Neural Networks

Authors: M. Zerikat, S. Chekroun

Abstract:

This paper proposes an effective adaptation learning algorithm based on artificial neural networks for speed control of an induction motor assumed to operate in a high-performance drives environment. The structure scheme consists of a neural network controller and an algorithm for changing the NN weights in order that the motor speed can accurately track of the reference command. This paper also makes uses a very realistic and practical scheme to estimate and adaptively learn the noise content in the speed load torque characteristic of the motor. The availability of the proposed controller is verified by through a laboratory implementation and under computation simulations with Matlab-software. The process is also tested for the tracking property using different types of reference signals. The performance and robustness of the proposed control scheme have evaluated under a variety of operating conditions of the induction motor drives. The obtained results demonstrate the effectiveness of the proposed control scheme system performances, both in steady state error in speed and dynamic conditions, was found to be excellent and those is not overshoot.

Keywords: Electric drive, Induction motor, speed control, Adaptive control, neural network, High Performance.

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474 Searching for Forensic Evidence in a Compromised Virtual Web Server against SQL Injection Attacks and PHP Web Shell

Authors: Gigih Supriyatno

Abstract:

SQL injection is one of the most common types of attacks and has a very critical impact on web servers. In the worst case, an attacker can perform post-exploitation after a successful SQL injection attack. In the case of forensics web servers, web server analysis is closely related to log file analysis. But sometimes large file sizes and different log types make it difficult for investigators to look for traces of attackers on the server. The purpose of this paper is to help investigator take appropriate steps to investigate when the web server gets attacked. We use attack scenarios using SQL injection attacks including PHP backdoor injection as post-exploitation. We perform post-mortem analysis of web server logs based on Hypertext Transfer Protocol (HTTP) POST and HTTP GET method approaches that are characteristic of SQL injection attacks. In addition, we also propose structured analysis method between the web server application log file, database application, and other additional logs that exist on the webserver. This method makes the investigator more structured to analyze the log file so as to produce evidence of attack with acceptable time. There is also the possibility that other attack techniques can be detected with this method. On the other side, it can help web administrators to prepare their systems for the forensic readiness.

Keywords: Web forensic, SQL injection, web shell, investigation.

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473 A Semi-Implicit Phase Field Model for Droplet Evolution

Authors: M. H. Kazemi, D. Salac

Abstract:

A semi-implicit phase field method for droplet evolution is proposed. Using the phase field Cahn-Hilliard equation, we are able to track the interface in multiphase flow. The idea of a semi-implicit finite difference scheme is reviewed and employed to solve two nonlinear equations, including the Navier-Stokes and the Cahn-Hilliard equations. The use of a semi-implicit method allows us to have larger time steps compared to explicit schemes. The governing equations are coupled and then solved by a GMRES solver (generalized minimal residual method) using modified Gram-Schmidt orthogonalization. To show the validity of the method, we apply the method to the simulation of a rising droplet, a leaky dielectric drop and the coalescence of drops. The numerical solutions to the phase field model match well with existing solutions over a defined range of variables.

Keywords: Coalescence, leaky dielectric, numerical method, phase field, rising droplet, semi-implicit method.

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472 Design of Regular Communication Area for Infrared Electronic-Toll-Collection Systems

Authors: Wern-Yarng Shieh, Chao Qian, Bingnan Pei

Abstract:

A design of communication area for infrared electronic-toll-collection systems to provide an extended communication interval in the vehicle traveling direction and regular boundary between contiguous traffic lanes is proposed. By utilizing two typical low-cost commercial infrared LEDs with different half-intensity angles Φ1/2 = 22◦ and 10◦, the radiation pattern of the emitter is designed to properly adjust the spatial distribution of the signal power. The aforementioned purpose can be achieved with an LED array in a three-piece structure with appropriate mounting angles. With this emitter, the influence of the mounting parameters, including the mounting height and mounting angles of the on-board unit and road-side unit, on the system performance in terms of the received signal strength and communication area are investigated. The results reveal that, for our emitter proposed in this paper, the ideal ”long-and-narrow” characteristic of the communication area is very little affected by these mounting parameters. An optimum mounting configuration is also suggested.

Keywords: Dedicated short-range communication (DSRC), electronic toll collection (ETC), infrared communication, intelligent transportation system (ITS), multilane free flow.

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471 Bioconversion of Biodiesel Derived Crude Glycerol by Immobilized Clostridium pasteurianum: Effect of Temperature

Authors: Swati Khanna, Arun Goyal, Vijayanand S. Moholkar

Abstract:

Batch fermentation of 5, 10 and 25 g/L biodiesel derived crude glycerol was carried out at 30, 37 and 450C by Clostridium pasteurianum cells immobilized on silica. Maximum yield of 1,3-propanediol (PDO) (0.60 mol/mol), and ethanol (0.26 mol/mol) were obtained from 10 g/L crude glycerol at 30 and 370C respectively. Maximum yield of butanol (0.28 mol/mol substrate added) was obtained at 370C with 25 g/L substrate. None of the three products were detected at 45oC even after 10 days of fermentation. Only traces of ethanol (0.01 mol/mol) were detected at 450C with 5 g/L substrate. The results obtained for 25 g/L substrate utilization were fitted in first order rate equation to obtain the values of rate constant at three different temperatures for bioconversion of glycerol. First order rate constants for bioconversion of glycerol at 30, 37 and 45oC were found to be 0.198, 0.294 and 0.029/day respectively. Activation energy (Ea) for crude glycerol bioconversion was calculated to be 57.62 kcal/mol.

Keywords: activation energy, Clostridium pasteurianum, crude glycerol, immobilization

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470 Simplified 3R2C Building Thermal Network Model: A Case Study

Authors: S. M. Mahbobur Rahman

Abstract:

Whole building energy simulation models are widely used for predicting future energy consumption, performance diagnosis and optimum control.  Black box building energy modeling approach has been heavily studied in the past decade. The thermal response of a building can also be modeled using a network of interconnected resistors (R) and capacitors (C) at each node called R-C network. In this study, a model building, Case 600, as described in the “Standard Method of Test for the Evaluation of Building Energy Analysis Computer Program”, ASHRAE standard 140, is studied along with a 3R2C thermal network model and the ASHRAE clear sky solar radiation model. Although building an energy model involves two important parts of building component i.e., the envelope and internal mass, the effect of building internal mass is not considered in this study. All the characteristic parameters of the building envelope are evaluated as on Case 600. Finally, monthly building energy consumption from the thermal network model is compared with a simple-box energy model within reasonable accuracy. From the results, 0.6-9.4% variation of monthly energy consumption is observed because of the south-facing windows.

Keywords: ASHRAE case study, clear sky solar radiation model, energy modeling, thermal network model.

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469 Novel Anti-leukemia Calanone Compounds by Quantitative Structure-Activity Relationship AM1 Semiempirical Method

Authors: Ponco Iswanto, Mochammad Chasani, Muhammad Hanafi, Iqmal Tahir, Eva Vaulina YD, Harjono, Lestari Solikhati, Winkanda S. Putra, Yayuk Yuliantini

Abstract:

Quantitative Structure-Activity Relationship (QSAR) approach for discovering novel more active Calanone derivative as anti-leukemia compound has been conducted. There are 6 experimental activities of Calanone compounds against leukemia cell L1210 that are used as material of the research. Calculation of theoretical predictors (independent variables) was performed by AM1 semiempirical method. The QSAR equation is determined by Principle Component Regression (PCR) analysis, with Log IC50 as dependent variable and the independent variables are atomic net charges, dipole moment (μ), and coefficient partition of noctanol/ water (Log P). Three novel Calanone derivatives that obtained by this research have higher activity against leukemia cell L1210 than pure Calanone.

Keywords: AM1 semiempirical calculation, Calanone, Principle Component Regression, QSAR approach.

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