Abstract: Virtual Reality Modelling Language (VRML) is description language, which belongs to a field Window on World virtual reality system. The file, which is in VRML format, can be interpreted by VRML explorer in three-dimensional scene. VRML was created with aim to represent virtual reality on Internet easier. Development of 3D graphic is connected with Silicon Graphic Corporation. VRML 2.0 is the file format for describing interactive 3D scenes and objects. It can be used in collaboration with www, can be used for 3D complex representations creating of scenes, products or VR applications VRML 2.0 enables represent static and animated objects too. Interesting application of VRML is in area of manufacturing systems presentation.
Abstract: In the present paper, we investigate a differential subordination
involving multiplier transformation related to a sector in the
open unit disk E = {z : |z| < 1}. As special cases to our main
result, certain sufficient conditions for strongly starlike and strongly
convex functions are obtained.
Abstract: The processing of the electrocardiogram (ECG) signal consists essentially in the detection of the characteristic points of
signal which are an important tool in the diagnosis of heart diseases. The most suitable are the detection of R waves. In this paper, we
present various mathematical tools used for filtering ECG using digital filtering and Discreet Wavelet Transform (DWT) filtering. In
addition, this paper will include two main R peak detection methods
by applying a windowing process: The first method is based on calculations derived, the second is a time-frequency method based on
Dyadic Wavelet Transform DyWT.
Abstract: Appropriate ventilation in a classroom is helpful for
enhancing air exchange rate and student concentration. This study
focuses on the effects of fenestration in a four-story school building by
performing numerical simulation of a building when considering
indoor and outdoor environments simultaneously. The wind profile
function embedded in PHOENICS code was set as the inlet boundary
condition in a suburban environment. Sixteen fenestration
combinations were compared in a classroom containing thirty seats.
This study evaluates mean age of air (AGE) and airflow pattern of a
classroom on different floors. Considering both wind profile and
fenestration effects, the airflow on higher floors is channeled toward
the area near ceiling in a room and causes older mean age of air in the
breathing zone. The results in this study serve as a useful guide for
enhancing natural ventilation in a typical school building.
Abstract: A preliminary evaluation of the feasibility of installing small wind turbines on offshore oil and gas extraction platforms is presented. Some aerodynamic considerations are developed in order to determine the best rotor architecture to exploit the wind potential on such installations, assuming that wind conditions over the platforms are similar to those registered on the roofs of urban buildings. Economical considerations about both advantages and disadvantages of the exploitation of wind energy on offshore extraction platforms with respect to conventional offshore wind plants, is also presented. Finally, wind charts of European offshore winds are presented together with a map of the major offshore installations.
Abstract: Growing world population has fundamental impacts
and often catastrophic on natural habitat. The immethodical
consumption of energy, destruction of the forests and extinction of
plant and animal species are the consequence of this experience.
Urban sustainability and sustainable urban development, that is so
spoken these days, should be considered as a strategy, goal and
policy, beyond just considering environmental issues and protection.
The desert-s climate has made a bunch of problems for its residents.
Very hot and dry climate in summers of the Iranian desert areas,
when there was no access to modern energy source and mechanical
cooling systems in the past, made Iranian architects to design a
natural ventilation system in their buildings. The structure, like a
tower going upward the roof, besides its ornamental application and
giving a beautiful view to the building, was used as a spontaneous
ventilation system. In this paper, it has been tried to name the
problems of the area and it-s inconvenience, then some answers has
pointed out in order to solve the problems and as an alternative
solution BADGIR (wind-catcher) has been introduced as a solution
knowing that it has been playing a major role in dealing with the
problems.
Abstract: A complete CAD procedure to model a twisted-bladed
vertical-axis wind turbine (VAWT) is presented with the aim of
determining some practical guidelines to be used for the generation
of an easily-meshable CAD geometry to be adopted as the basis of
both CFD and FEM numerical simulations.
Abstract: In this study, aeroelastic response and performance
analyses have been conducted for a 5MW-Class composite wind
turbine blade model. Advanced coupled numerical method based on
computational fluid dynamics (CFD) and computational flexible
multi-body dynamics (CFMBD) has been developed in order to
investigate aeroelastic responses and performance characteristics of
the rotating composite blade. Reynolds-Averaged Navier-Stokes
(RANS) equations with k-ω SST turbulence model were solved for
unsteady flow problems on the rotating turbine blade model. Also,
structural analyses considering rotating effect have been conducted
using the general nonlinear finite element method. A fully implicit
time marching scheme based on the Newmark direct integration
method is applied to solve the coupled aeroelastic governing equations
of the 3D turbine blade for fluid-structure interaction (FSI) problems.
Detailed dynamic responses and instantaneous velocity contour on the
blade surfaces which considering flow-separation effects were
presented to show the multi-physical phenomenon of the huge rotating
wind- turbine blade model.
Abstract: Renewed interest in propeller propulsion on aircraft
configurations combined with higher propeller loads lead to the question how the effects of the propulsion on model support disturbances
should be accounted for. In this paper, the determination of engine power effects on support interference of sting-mounted models is
demonstrated by a measurement on a four-engine turboprop aircraft.
CFD results on a more generic model are presented in order to clarify
the possible mechanism behind engine power effects on support
interference. The engine slipstream induces a local change in angle
of sideslip at the model sting thereby influencing the sting near-field and far-field effects. Whether or not the net result of these changes
in the disturbance pattern leads to a significant engine power effect depends on the configuration of the wind tunnel model and the test
setup.
Abstract: This paper proposes the method combining artificial
neural network (ANN) with particle swarm optimization (PSO) to
implement the maximum power point tracking (MPPT) by controlling
the rotor speed of the wind generator. First, the measurements of wind
speed, rotor speed of wind power generator and output power of wind
power generator are applied to train artificial neural network and to
estimate the wind speed. Second, the method mentioned above is
applied to estimate and control the optimal rotor speed of the wind
turbine so as to output the maximum power. Finally, the result reveals
that the control system discussed in this paper extracts the maximum
output power of wind generator within the short duration even in the
conditions of wind speed and load impedance variation.
Abstract: Applying corona wind as a novel technique can lead
to a great level of heat and mass transfer augmentation by using very
small amount of energy. Enhancement of forced flow evaporation
rate by applying electric field (corona wind) has been experimentally
evaluated in this study. Corona wind produced by a fine wire
electrode which is charged with positive high DC voltage impinges
to water surface and leads to evaporation enhancement by disturbing
the saturated air layer over water surface. The study was focused on
the effect of corona wind velocity, electrode spacing and air flow
velocity on the level of evaporation enhancement. Two sets of
experiments, i.e. with and without electric field, have been
conducted. Data obtained from the first experiment were used as
reference for evaluation of evaporation enhancement at the presence
of electric field. Applied voltages ranged from corona threshold
voltage to spark over voltage at 1 kV increments. The results showed
that corona wind has great enhancement effect on water evaporation
rate, but its effectiveness gradually diminishes by increasing air flow
velocity. Maximum enhancements were 7.3 and 3.6 for air velocities
of 0.125 and 1.75 m/s, respectively.
Abstract: Optimal load shedding (LS) design as an emergency plan is one of the main control challenges posed by emerging new uncertainties and numerous distributed generators including renewable energy sources in a modern power system. This paper presents an overview of the key issues and new challenges on optimal LS synthesis concerning the integration of wind turbine units into the power systems. Following a brief survey on the existing LS methods, the impact of power fluctuation produced by wind powers on system frequency and voltage performance is presented. The most LS schemas proposed so far used voltage or frequency parameter via under-frequency or under-voltage LS schemes. Here, the necessity of considering both voltage and frequency indices to achieve a more effective and comprehensive LS strategy is emphasized. Then it is clarified that this problem will be more dominated in the presence of wind turbines.
Abstract: In North America, Most power distribution systems
employ a four-wire multi-grounded neutral (MGN) design. This paper has explained the inherent characteristics of multi-grounded three-phase four-wire distribution systems under unbalanced
situations. As a result, the mechanism of voltage swell and voltage sag in MGN feeders becomes difficult to understand. The simulation
tool that has been used in this paper is MATLAB under Windows software. In this paper the equivalent model of a full-scale multigrounded
distribution system implemented by MATLAB is
introduced. The results are expected to help utility engineers to understand the impact of MGN on distribution system operations.
Abstract: Model Predictive Control (MPC) is increasingly being
proposed for real time applications and embedded systems. However
comparing to PID controller, the implementation of the MPC in
miniaturized devices like Field Programmable Gate Arrays (FPGA)
and microcontrollers has historically been very small scale due to its
complexity in implementation and its computation time requirement.
At the same time, such embedded technologies have become an
enabler for future manufacturing enterprises as well as a transformer
of organizations and markets. Recently, advances in microelectronics
and software allow such technique to be implemented in embedded
systems. In this work, we take advantage of these recent advances
in this area in the deployment of one of the most studied and
applied control technique in the industrial engineering. In fact in
this paper, we propose an efficient framework for implementation
of Generalized Predictive Control (GPC) in the performed STM32
microcontroller. The STM32 keil starter kit based on a JTAG interface
and the STM32 board was used to implement the proposed GPC
firmware. Besides the GPC, the PID anti windup algorithm was
also implemented using Keil development tools designed for ARM
processor-based microcontroller devices and working with C/Cµ
langage. A performances comparison study was done between both
firmwares. This performances study show good execution speed and
low computational burden. These results encourage to develop simple
predictive algorithms to be programmed in industrial standard hardware.
The main features of the proposed framework are illustrated
through two examples and compared with the anti windup PID
controller.
Abstract: Smoothing or filtering of data is first preprocessing step
for noise suppression in many applications involving data analysis.
Moving average is the most popular method of smoothing the data,
generalization of this led to the development of Savitzky-Golay filter.
Many window smoothing methods were developed by convolving
the data with different window functions for different applications;
most widely used window functions are Gaussian or Kaiser. Function
approximation of the data by polynomial regression or Fourier
expansion or wavelet expansion also gives a smoothed data. Wavelets
also smooth the data to great extent by thresholding the wavelet
coefficients. Almost all smoothing methods destroys the peaks and
flatten them when the support of the window is increased. In certain
applications it is desirable to retain peaks while smoothing the data
as much as possible. In this paper we present a methodology called
as peak-wise smoothing that will smooth the data to any desired level
without losing the major peak features.
Abstract: Demand of energy is increasing faster than the
generation. It leads shortage of power in all sectors of society. At
peak hours this shortage is higher. Unless we utilize energy efficient
technology, it is very difficult to minimize the shortage of energy. So
energy efficiency program and energy conservation has an important
role. Energy efficient technologies are cost intensive hence it is
always not possible to implement in country like India. In the recent
study, an educational building with operating hours from 10:00 a.m.
to 05:00 p.m. has been selected to quantify the possibility of lighting
energy conservation. As the operating hour is in daytime, integration
of daylight with artificial lighting system will definitely reduce the
lighting energy consumption. Moreover the initial investment has
been given priority and hence the existing lighting installation was
unaltered. An automatic controller has been designed which will be
operated as a function of daylight through windows and the lighting
system of the room will function accordingly. The result of the study
of integrating daylight gave quite satisfactory for visual comfort as
well as energy conservation.
Abstract: This paper presents a robust method to detect obstacles in stereo images using shadow removal technique and color information. Stereo vision based obstacle detection is an algorithm that aims to detect and compute obstacle depth using stereo matching and disparity map. The proposed advanced method is divided into three phases, the first phase is detecting obstacles and removing shadows, the second one is matching and the last phase is depth computing. We propose a robust method for detecting obstacles in stereo images using a shadow removal technique based on color information in HIS space, at the first phase. In this paper we use Normalized Cross Correlation (NCC) function matching with a 5 × 5 window and prepare an empty matching table τ and start growing disparity components by drawing a seed s from S which is computed using canny edge detector, and adding it to τ. In this way we achieve higher performance than the previous works [2,17]. A fast stereo matching algorithm is proposed that visits only a small fraction of disparity space in order to find a semi-dense disparity map. It works by growing from a small set of correspondence seeds. The obstacle identified in phase one which appears in the disparity map of phase two enters to the third phase of depth computing. Finally, experimental results are presented to show the effectiveness of the proposed method.
Abstract: The three-time-scale plant model of a wind power
generator, including a wind turbine, a flexible vertical shaft, a Variable
Inertia Flywheel (VIF) module, an Active Magnetic Bearing (AMB)
unit and the applied wind sequence, is constructed. In order to make
the wind power generator be still able to operate as the spindle speed
exceeds its rated speed, the VIF is equipped so that the spindle speed
can be appropriately slowed down once any stronger wind field is
exerted. To prevent any potential damage due to collision by shaft
against conventional bearings, the AMB unit is proposed to regulate
the shaft position deviation. By singular perturbation order-reduction
technique, a lower-order plant model can be established for the
synthesis of feedback controller. Two major system parameter
uncertainties, an additive uncertainty and a multiplicative uncertainty,
are constituted by the wind turbine and the VIF respectively.
Frequency Shaping Sliding Mode Control (FSSMC) loop is proposed
to account for these uncertainties and suppress the unmodeled
higher-order plant dynamics. At last, the efficacy of the FSSMC is
verified by intensive computer and experimental simulations for
regulation on position deviation of the shaft and counter-balance of
unpredictable wind disturbance.
Abstract: Cyber physical system (CPS) for target tracking, military surveillance, human health monitoring, and vehicle detection all require maximizing the utility and saving the energy. Sensor selection is one of the most important parts of CPS. Sensor selection problem (SSP) is concentrating to balance the tradeoff between the number of sensors which we used and the utility which we will get. In this paper, we propose a performance constrained slide windows (PCSW) based algorithm for SSP in CPS. we present results of extensive simulations that we have carried out to test and validate the PCSW algorithms when we track a target, Experiment shows that the PCSW based algorithm improved the performance including selecting time and communication times for selecting.
Abstract: This research aims to develop and evaluate a training
course to promote learning activities of 2nd year, Suan Sunandha
Rajabhat University, faculty of education students using multiple
intelligences theory. The process is divided into two phases: Phase 1
development of training course to promote learning activities
consisting of principles, objectives of the course, structure, training
duration, content, training materials, training activities, media
training, monitoring, measurement and evaluation quality of the
course. Phase 2 evaluation efficiency of training course was to use
the improved curriculum with experimental group which is 2nd year,
Suan Sunandha Rajabhat University, faculty of education students
was drawn randomly 152 students. The experimental pattern was
randomized Control Group Pre-Test Post-Test Design, Analysis Data
by t-Test with the software SPFSS for Windows. Research has shown
that: 1). the ability of teaching and learning according to the theory of
multiple intelligences after training is higher than before training
significantly in statistic at .01 level, 2). The satisfaction of students
to the training courses was overall at the highest level.