Voltage support and stability improvement using unified power flow controller tuned based on simulated annealing
September 2011
In this paper, the authors are willing to study the effects of unified power flow controller (UPFC) on voltage support and also stability enhancement at a multi-machine electric power system. Proportional-Integral (PI) type controllers are considered for UPFC control and the parameters of these PI type controllers are tuned using simulated annealing (SA). In order to show the ability of UPFC in voltage control and...
Implementation of proportional integral (PI) controlled DSP based cost effective inverter fed speed control of induction motor drive with VisSim/ embedded controls and developer (ECD)
September 2011
Real-time implementation of PI controller based cost effective inverter fed speed control of induction motor drive using high performance TMS320F2812 DSP with VisSim/ embedded controls and developer (ECD) is presented in this paper. The four switch three-phase inverter (FSTPI) fed drive system consists of a power circuit having an insulated gate bipolar junction transistor (IGBT) based bridge inverter module feeding a 5...
Determination of mass attenuation coefficients for natural minerals from different places of Turkey
September 2011
The mass attenuation coefficients () for some natural minerals taken from different places of Turkey were measured at various low photon energies. The Am-241 radioactive source and Zr and Cd secondary exciter are used to get photons in the energy range 15.8 to 26.2 keV. For each sample and energy, Io and I intensities which are without and after attenuation were measured by a Si(Li) detector...
Hi-tech manufacturing process selection problem for very low fraction of defectives with multiple characteristics
September 2011
Hi-tech manufacturing process selection is the problem of comparing two processes and selecting the one that has a very low fraction of defectives (VLFD). In this paper, we consider process selection by , which is an extension of the widely-used popular indexCpk to cases with multiple characteristics. We propose an analytical approach is proposed to tackle the process selection problem. Hypothesis testing...
Synchronization and anti-synchronization of two identical hyperchaotic systems based on active backstepping design
September 2011
This paper presents an active backstepping design method for synchronization and anti-synchronization of two identical hyperchaotic Chen systems. The proposed control method, combining backstepping design and active control approach, extends the application of backstepping technique in chaos control. Based on this method, different combinations of controllers can be designed to meet the needs of different applications....
Mitigating the control channel bottleneck problem in dense cognitive radio networks
September 2011
We proposed a group-based multi channel media access control protocol for cognitive radio to mitigate the control channel bottleneck issue and to utilize multiple channels efficiently. The existing multichannel media access control (MMAC) based protocols suffer from higher delay to access data channels. This underutilizes data channels and lowers the network goodput in dense cognitive radio networks. Our approach...
Feature classification for multi-focus image fusion
September 2011
Image processing techniques have witnessed increased usage in various real world applications. For any image processing technique, such as image segmentation, restoration, edge detection, stereo matching etc., to be applied successfully, the image under consideration must contain all of the scene objects in focus. Usually, due to inadequate depth of field of optical lenses, especially with larger focal length, it...
Ouagadougou station F2 layer parameters, yearly and seasonal variations during severe geomagnetic storms generated by coronal mass ejections (CMEs) and fluctuating wind streams
September 2011
Solar sources of geomagnetic activity are determined by means of (1) Mayaud aa index values from 1868 to now; (2) sudden storm commencement (SSC) dates and (3) pixel diagrams. From 1966 to 1998 that is, during 33 years severe geomagnetic storms characterised by aa > = 100 nT have been identified and their solar sources determined. During these three solar cycles (cycles 20, 21 and 22) the effects of these solar...
Spatial rainfall analysis for an urbanized tropical river basin
September 2011
Spatial distributions of the storms are important since it is a major factor influencing flood formation in urban areas. However, the spatial allocations of rainfall data obtained from the interpolation method have many uncertainties. Thus, it is the objective of this research to derive the spatial distribution of storm events by using grid-based Kriging method. The best semi-variogram (SV) model is found for Kriging...
Meshfree modeling of shape memory alloy wires thermomechanical behavior
September 2011
In this research, a macro-scale, phenomenological constitutive model for shape memory alloy (SMA) is used in conjunction with energy balance equations to study the evolution of temperature and deformation profiles seen in SMA wires. In this way, the general fully-coupled thermomechanical formula for resistive heating of an SMA wire-initial detwined martensite, leading to strain recovery on heating, is used and numerical...
Spatial rainfall analysis for an urbanized tropical river basin
September 2011
Spatial distributions of the storms are important since it is a major factor influencing flood formation in urban areas. However, the spatial allocations of rainfall data obtained from the interpolation method have many uncertainties. Thus, it is the objective of this research to derive the spatial distribution of storm events by using grid-based Kriging method. The best semi-variogram (SV) model is found for Kriging...
Preparation of nickel nanowire within polycarbonate membrane and removing polycarbonate by KrF excimer laser
September 2011
Nikel nanowire arrays were fabricated by potentiostatic electrodeposition into track-etched polycarbonate (PC) membranes. By electrochemical deposition of nickel, nanowires were grown in the single pores. The nanowires were contacted by sputtering a gold layer on top of the membrane. The distinct difference in laser ablation thresholds offers the selective material removal. After preparation of nanowires, polycarbonate...
Path planning for a mobile robot in dynamic environments
September 2011
Path planning for mobile robots has been gaining extensive research attention recently. Optimal path planning increases the effectiveness of a mobile robot. There are many algorithms to solve the path planning problems overcoming obstacles. However most of the algorithms are applicable to specific shapes or suitable for static environments. This paper introduces a new method of global path planning for a robot moving in...
Effect of amending urea with humic acids and acid sulphate on biomass production of Masmadu (Zea mays L.) and selected soil chemical properties
September 2011
Excessive use of fertilizers especially nitrogenous fertilizers with low management in relation to food safety and environmental pollution has in recent times become a subject of concern. This greenhouse study compared the effect of three different urea-humic acid-acid sulphate soil mixtures on maize biomass production, soil pH, ammonium and nitrate contents, and urea use efficiency compared with urea-N...
Optimal route choice in stochastic time-varying transportation networks considering on-time arrival probability
September 2011
This paper studies the problem of finding a priori optimal paths to guarantee a maximum likelihood of arriving on-time in a stochastic time-varying transportation network. The reliable path can help travelers better plan their trip by measuring the risk of late under uncertain conditions. We first identify a set of mathematical relationships between the on-time arrival probability, mean and variance of the dynamic and...
Weighting method for modal parameter based damage detection algorithms
September 2011
When researchers use bending modes for the purpose of damage detection, a number of available modes are adopted, each of which return a value indicating the severity of damage. Normally, there is a variance in the sensitivity of different modes and the global stiffness change is derived by taking the algebraic average, which is equivalent to the mean in statistical analysis terms. This study proposes weighting method...
A critical review of parallel distributed computing and the Lyapunov criterion for multiple time-delay fuzzy systems
September 2011
This work reviews some important Lyapunov criterion results based on which we address the stability problems of multiple time-delay Takagi-Sugeno (T-S) fuzzy systems. A delay-dependent stability criterion is derived using the fuzzy Lyapunov method that will ensure the asymptotic stability of the multiple time-delay T-S fuzzy systems. Furthermore, the parallel distributed compensation (PDC) scheme is used to achieve a...
A new approach for interval type-2 by using adaptive network based fuzzy inference system
September 2011
In this paper, adaptive network based fuzzy inference system (ANFIS) was used in control applications of different type nonlinear systems as interval type-2 fuzzy logic controller (IT-2FL). Two adaptive network based fuzzy inference systems were chosen to design type-2 fuzzy logic controllers for each control applications. Membership functions in interval type-2 fuzzy logic controllers were set as an area called...
Thermal insulation and physical properties of particleboards from pineapple leaves
September 2011
The aims of this research were to study the production processes and properties of thermal insulation produced from pineapple leaves using natural rubber latex as a binder. Thermal insulation boards were made by spraying the pretreated natural rubber latex onto pineapple fiber to form a squared thermal insulation with the size of 20 and 1.5 cm thickness. Test results on thermal and physical properties showed that...
Capability measures for Weibull processes with mean shift based on Erto’s-Weibull control chart
September 2011
Process capability indices (PCIs), which are effective tools for quality assurance and are guidance for process improvement, have been proposed in the manufacturing industry to provide numerical measures on process reproduction capability. PCIs are calculated under the assumption that the process is stable while the process mean and variation are not changeable. However, in practice, the process is dynamic. Under the...
Self-managing defense against SYN-flooding attacks
September 2011
SYN-flooding attack uses the weakness available in TCP’s three-way handshake process to keep it from handling legitimate requests. This attack causes the victim host to populate its backlog queue with forged TCP connections. In other words it increases PSA (probability of success of attack) and decreases BUE (buffer utilization efficiency) in the victim host and results to decreased performance of the host. This...
Investigation of induction motor parameter identification using particle swarm optimization-based RBF neural network (PSO-RBFNN)
September 2011
High dynamic performance of induction motor drives is required for accurate system information. From the actual parameters, it is possible to design high performance induction motor drive controllers. In this paper, improving the induction motor performance using intelligent parameter identification was proposed. First, machine model parameters were presented by a set of time-varying differential equations. Second,...
Quantum hybrid genetic algorithm based on simulated annealing and its application
September 2011
Quantum genetic algorithm (QGA) is firstly improved for numerical optimization with real coding, where populations are updated by a simple rotation method which inspires a real quantum genetic algorithm (RQGA), then simulated annealing (SA) is reasonably introduced in the optimizing process of RQGA, and a hybrid quantum genetic algorithm (HQGA) is presented, which could not only effectively avoid the premature...
Correlation of UV irradiation-induced wettability characteristics by factorial design of experiments on Ti6Al4V
September 2011
Biomimetic surface roughness and UV irradiation time will greatly affect their use of hydrophilic and hydrophobic surface of biological material, and then in turn affect cell adhesion, cell growth quality. Therefore, the main purpose of this study in different surface modification treatments on Ti6Al4V discs which around irradiation with UV light influence the wettability on the material surface. Then, Factorial design...
Computerized nuchal translucency three dimensional reconstruction, visualization and measurement for trisomy 21 prenatal early assessment
September 2011
Conventionally, measurement of ultrasonic marker, nuchal translucency or NT is accomplished by manual assessment in two dimensional ultrasound images for trisomy 21 early detection. Nonetheless, the efficiency of 2D measurement depends heavily on the image position and any deviation will prompt inaccurate measurement. Therefore, in this paper we proposed the reconstruction, visualization and measurement of nuchal...
Sensitivity analysis of slopes affected by possible earthquake loading and heavy rainfall: Case study
September 2011
The effect of seismic loading on slope failure is studied both experimentally and analytically to establish the spatial and temporal process of failure initiation and propagation during possible earthquake loading or heavy rainfall. For such purpose different limit equilibrium modeling were carried out and factor of safeties against sliding caused by both excess earthquake loading and heavy rainfall were found. As for...
A hybrid Ant algorithm for the set covering problem
September 2011
Set covering problem is the model for many important industrial applications. In this paper, we solve some benchmarks of this problem with ant colony optimization algorithms using a new transition rule. A look-ahead mechanism was incorporated to check constraint consistency in ant computing. Computational results are presented showing the advantages to use this additional mechanism to ant system and ant colony...
Statistical evaluation of wind speed and energy potential for the construction of a power plant in Baladeh, Nur, Northern Iran
September 2011
Renewable energy does not pollute the environment and it has an endless and free primary source and save fossil fuel reserves for future generations. Finding and confirming the appropriate potential areas for installing wind turbines is the first and the most important step for constructing wind power plants. Hence, installing a standard anemometer station and checking wind flow regime is essential. In...
An analysis on the application of PID controller in the frequency contribution of gas turbine power plant
September 2011
Conventionally, frequency correction is made by water turbine power plants. This paper addresses the role of the gas turbine power plants in frequency correction within the power networks. It gives those conditions that are necessary for a gas turbine power plant that attends in frequency correction task. It studies the functional behavior of the governor system by using extensive simulations in MATLAB environment and...
The worst case upper bounds in #3-SAT with the number of clauses as the parameter
September 2011
The rigorous theoretical analyses of algorithms for #SAT problem had been proposed in recent years. However, as far as we know, all algorithms for solving #SAT had been analyzed using the number of variables as parameter. In this paper, an algorithm for #3-SAT with rigorous complexity analyses using the number of clauses as parameter was presented. By analyzing the algorithm, the worst-case upper...
Effect of soil water retention model on slope stability analysis
September 2011
Understanding of the relationship between volumetric water content (q) and soil capillary pressure (ψ), and between unsaturated hydraulic conductivity K and ψ is important in the analysis of rainwater infiltration into soil and its effect to slope stability. These relationships are known as the water retention curve and the hydraulic conductivity function, respectively. Much soil water...
The role of global warming in the reservoir storage drop at Kainji dam in Nigeria
September 2011
Statistical analysis of hydrometeorological data (temperature, relative humidity, rainfall, reservoir inflow, reservoir storage and turbine release) at Kainji dam was done with the aim of detecting trends. The non parametric Man-Kendall test was used to detect monotonic trends. The Sen’s slope estimator and regression analysis were used to develop models for the variables. A Man-Kendall statistic...
Effects of friction stir welding process parameters on appearance and strength of polypropylene composite welds
September 2011
Friction stir welding is a solid-state joining process that has gained acceptable progress in recent years. This method which was first used for welding of aluminum and its alloys is now employed for welding of other materials such as polymers and composites. In this article, friction stir welding has been used for butt joining polypropylene composite plates having 30% glass fiber by weight. The effects of important...
Hub location selection of third-party logistics service on multiple countries consolidations for ocean freight forwarders by using fuzzy multiple criteria decision-making (MCDM) approach
September 2011
Since a good location will effectively help expand agglomeration economy effects and increase competitive advantages, there is a need to proceed with a study on effects from various perspectives and evaluate proper location objectively. Hence, the main purpose of this paper is to use a fuzzy multiple criteria decision-making (MCDM) approach to select a hub location of third-party logistics service on multiple countries...
Quantum mechanical disclosure of the classical adiabatic constancy of pvg for both an ideal and a photon gas
September 2011
In our recent paper (Yarman et al., 2010), we established a connection between the macroscopic adiabatic transformation law (Pressure ´ Volume5/3= Constant) of an ideal gas and the quantum mechanical description of its molecules. This connection was unique in embodying just the Planck contant and quantum numbers, instead of the classical temperature quantity and Boltzmann constant. It was...
Investigation of discrepancies of some geoids determined using various methods for Turkey
September 2011
In this study, the causes and size of discrepancies between various geoid models were investigated. Local geoid models (Turkish Geoid-1991, Turkish GPS/Leveling Geoid, Updated Turkish Geoid-1999, Turkish Geoid-2003, Turkish Hybrid Geoid Model-2009) and global geoid models (EIGEN-GL04C, EIGEN-GL04S1, EIGEN-5C) were used in Turkey. Thirty different points were selected in Turkey. The geoid heights of the points in...
An investigation of carburization resistance performance of ethylene furnace tube alloys
September 2011
Carburization tests and analysis were performed on some samples of radiant tube alloys of ethylene furnaces at three petrochemical plants. These tubes had undergone carburization in service with some losing their structural integrity. This study evaluates and compares the carburization resistance performances of some of these tubes in service and identifies the cause of their degradation. The polished surfaces of the...
Thermal stabilizers for poly(vinyl chloride): A review
September 2011
Poly(vinyl chloride) (PVC) is one of the most important commercial plastic materials, but it is thermally unstable at processing temperature. Processing of PVC at elevated temperatures requires the use of thermal stabilizers. Widely used thermal stabilizers for PVC incorporate toxic heavy metal and organo-tin compounds that have been severely criticized based on environmental concern. In order to address this issue,...
Investigation on synthesis and size control of copper nanoparticle via electrochemical and chemical reduction method
September 2011
Copper nanoparticles were synthesized and the effect of the operating conditions via both chemical and electrochemical synthesis methods was investigated in this paper. In the chemical reduction method, copper nanoparticles were prepared in a copper sulfate solution using NaBH4 as reducing agent and then stabilized in the presence of polyvinylpyrrolidone under nitrogen atmosphere. Temperature and...
A model about our Galaxy
September 2011
We assumed the energy flow of the nuclear related with Dirac field, and compared it with Dirac equation. We found that energy flow equation has the same form with Dirac equation. There have been results taken from different item, which has the same mass of the energy that changed trend as the clock changed. We calculated the relationship of mass and radius of planet in solar system with the equations just to compare...
The spatial and volumetric variations of radon in Bangalore Metropolitan, India
September 2011
Radon levels have been measured in houses at ten different locations of Bangalore City, India. The study was focused on the basis of quality of construction, age of building and room volume. Solid state nuclear track detectors were used for measuring the concentrations. The average spatial values of 222Rn and 220Rn concentrations were found to be 33.4 ± 6.1 and 21.6 ± 2.5 Bqm-3, respectively....
Detection of fault location in the transmission lines with voltage sampling and CT deletion by network impedance matrix method
September 2011
There are a lot of methods for fault location using synchronized phasor measurement. Most of these methods are based on using measured voltage and current in one or two ends of a transmission line. Current measurement accuracy is limited according to the used current transformer’s (CT) accuracy. In this paper, besides various methods of fault distance location detection in power transmission lines, a new method...
Electrical, structural and optical properties of ZnO thin films grown by pulsed laser deposition
September 2011
We report the influence of oxygen partial pressure (PO2) on the electrical, structural and optical properties of no-stoichiometric ZnO (ZnO1-d) thin films grown by Nd:YAG pulsed laser deposition. We note that the electrical resistance of the ZnO1-d thin films is significantly modified by oxygen pressure; the electrical resistance decreases with the O2pressure in the range of 10 to 40...
Modeling and simulation of maglev train-guideway-tunnel-soil system for vibration
September 2011
A maglev train-guideway-tunnel-soil coupling system model is developed to study the wave propagation problem caused by high speed electromagnetic suspension (EMS) maglev train travelling through tunnel. The maglev train is simulated by multi-bodies, which takes the rigid body characteristics of the body-bogie-magnet system into account. The guideway-tunnel-soil system is simulated by 3D finite elements, and the...
Bayesian networks for defining relationships among climate factors
September 2011
Factors that shape the weather are studied to design models to make predictions. Understanding the relationships among these factors contribute to a better knowledge of atmospheric phenomena. However, conventional statistical techniques do not take into account the dependent relationships among these factors. Bayesian learning models are used in learning processes, which consist in quantification of conditional...
3D numerical definition with vectors for human smiles
September 2011
In most of the numerical methods for facial expressions in the literatures, the number of the key controls for animators or robot programmers are too complex and trivial, because what they want are less and critical controls. This study explored varied types of human smiles and extracted proper key factors affecting the smiles. These key factors then were converted into a set of control points which could serve to...
Groundwater quality assessment of Labuan Island
September 2011
Groundwater is known as an important source of water supply due to its relatively low susceptibility to pollution in comparison to surface water, and its large storage capacity (USEPA, 1985). It should be mentioned that water pollution is any physical, chemical or biological change in the quality of water that has a harmful effect on any living thing that drinks, uses or lives in it. When humans drink polluted water, it...
Modelling morbidity related absenteeism among workers in University of Ibadan Community, Nigeria: Poisson regression
September 2011
Globally, sickness absenteeism is a contemporary public health problem, particularly in developing countries. However, very few studies had addressed the theoretical and methodological aspects of health related absenteeism among University workers. A retrospective study of sickness records of 4447 employees of University of Ibadan made available at the University Staff Clinic (Jaja). The health records of each staff for...
Semantic discovery of web services using principal component analysis
September 2011
With the increase in the number of available web services, searching for appropriate web services fulfilling the service discoverer’s functional requirements has become as major challenge. Web services standards, in their present format support only keyword based search and many services which can fulfill the user’s requirements are not retrieved. Basic requirement for efficient service discovery is to...
Speech control of a teleoperated mobile humanoid robot
September 2011
This paper presents a mobile humanoid robot platform which is able to understand humans' speech commands in teleoperation environments. For service in unstructured environments, the robot must operate efficiently under active auditory perception system to ensure a coordinated human-robot system. First, the speech-based teleoperation control is introduced, with the cameras mounting on the robots, transmitting the...
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