Abstract: A multi fingered dexterous anthropomorphic hand is
being developed by the authors. The focus of the hand is the
replacement of human operators in hazardous environments and also
in environments where zero tolerance is observed for the human
errors. The robotic hand will comprise of five fingers (four fingers
and one thumb) each having four degrees of freedom (DOF) which
can perform flexion, extension, abduction, adduction and also
circumduction. For the actuation purpose pneumatic muscles and
springs will be used. The paper exemplifies the mechanical design for
the robotic hand. It also describes different mechanical designs that
have been developed before date.
Abstract: Direct Torque Control is a control technique in AC
drive systems to obtain high performance torque control. The
conventional DTC drive contains a pair of hysteresis comparators.
DTC drives utilizing hysteresis comparators suffer from high torque
ripple and variable switching frequency. The most common solution
to those problems is to use the space vector depends on the reference
torque and flux. In this Paper The space vector modulation technique
(SVPWM) is applied to 2 level inverter control in the proposed
DTC-based induction motor drive system, thereby dramatically
reducing the torque ripple. Then the controller based on space vector
modulation is designed to be applied in the control of Induction
Motor (IM) with a three-level Inverter. This type of Inverter has
several advantages over the standard two-level VSI, such as a greater
number of levels in the output voltage waveforms, Lower dV/dt, less
harmonic distortion in voltage and current waveforms and lower
switching frequencies. This paper proposes a general SVPWM
algorithm for three-level based on standard two-level SVPWM. The
proposed scheme is described clearly and simulation results are
reported to demonstrate its effectiveness. The entire control scheme is
implemented with Matlab/Simulink.
Abstract: The aim of this study was to investigate whether
magnetite nanoparticles affect the viability of Bradyrhizobium
japanicum cells residing on the surface of soybean seeds during
desiccation. Different concentrations of nanoparticles suspended in
liquid medium, mixed with and adhering to Bradyrhizobium
japanicum, were investigated at two temperatures, using both
soybean seeds and glass beads as surrogates. Statistical design was a
complete randomized block (CRB) in a factorial 6×2×2×6
experimental arrangement with four replications. The most important
variable was the viability of Bradyrhizobium on the surface of the
seeds. The nanoparticles increased Bradyrhizobium viability and
inoculated seeds stored at low temperature had greater viability when
nanoparticles had been added. At the optimum nanoparticle
concentration, 50% bacterium viability on the seeds was retained
after 5 days at 4ºC. Possible explanations for the observed effects are
proposed.
Abstract: The combustion chamber dimensions have important
effects on pollutant emission in furnaces as a direct result of
temperature distribution and maximum temperature value. In this
paper the pollutant emission and the temperature distribution in two
cylindrical furnaces with different dimensions (with similar length to
diameter ratio) in similar condition have been investigated
experimentally. The furnace fuel is gas oil that is used with three
different flow rates. The results show that in these two cases the
temperature increases to its maximum value quickly, and then
decreases slowly. The results also show that increase in fuel flow rate
cause to increase in NOx emission in each case, but this increase is
greater in small furnace. With increase in fuel flow rate, CO emission
decreases firstly, and then it increases. Combustion efficiency
reduces with increase in fuel flow rate but the rate of reduction in
small furnace is greater than large furnace. The results of axial
temperature distribution have been compared with those have been
obtained numerically and experimentally by Moghiman.
Abstract: A fault detection and identification (FDI) technique is
presented to create a fault tolerant control system (FTC). The fault
detection is achieved by monitoring the position of the light source
using an array of light sensors. When a decision is made about the
presence of a fault an identification process is initiated to locate the
faulty component and reconfigure the controller signals. The signals
provided by the sensors are predictable; therefore the existence of a
fault is easily identified. Identification of the faulty sensor is based on
the dynamics of the frame. The technique is not restricted to a
particular type of controllers and the results show consistency.
Abstract: In this work, we address theoretically the influence of red and white Gaussian noise for electronic energies and eigenstates of cylindrically shaped quantum dots. The stochastic effect can be imagined as resulting from crystal-growth statistical fluctuations in the quantum-dot material composition. In particular we obtain analytical expressions for the eigenvalue shifts and electronic envelope functions in the k . p formalism due to stochastic variations in the confining band-edge potential. It is shown that white noise in the band-edge potential leaves electronic properties almost unaffected while red noise may lead to changes in state energies and envelopefunction amplitudes of several percentages. In the latter case, the ensemble-averaged envelope function decays as a function of distance. It is also shown that, in a stochastic system, constant ensembleaveraged envelope functions are the only bounded solutions for the infinite quantum-wire problem and the energy spectrum is completely discrete. In other words, the infinite stochastic quantum wire behaves, ensemble-averaged, as an atom.
Abstract: Wind catchers are traditional natural ventilation
systems attached to buildings in order to ventilate the indoor air. The
most common type of wind catcher is four sided one which is
capable to catch wind in all directions. CFD simulation is the perfect
way to evaluate the wind catcher performance. The accuracy of CFD
results is the issue of concern, so sensitivity analyses is crucial to
find out the effect of different settings of CFD on results. This paper
presents a series of 3D steady RANS simulations for a generic
isolated four-sided wind catcher attached to a room subjected to wind
direction ranging from 0º to 180º with an interval of 45º. The CFD
simulations are validated with detailed wind tunnel experiments. The
influence of an extensive range of computational parameters is
explored in this paper, including the resolution of the computational
grid, the size of the computational domain and the turbulence model.
This study found that CFD simulation is a reliable method for wind
catcher study, but it is less accurate in prediction of models with non
perpendicular wind directions.
Abstract: Turbulent heat transfer to fluid flow through channel with triangular ribs of different angles are presented in this paper. Ansys 14 ICEM and Ansys 14 Fluent are used for meshing process and solving Navier stokes equations respectively. In this investigation three angles of triangular ribs with the range of Reynolds number varied from 20000 to 60000 at constant surface temperature are considered. The results show that the Nusselt number increases with the increase of Reynolds number for all cases at constant surface temperature. According to the profile of local Nusselt number on ribs walled of channel, the peak is at the midpoint between the two ribs. The maximum value of average Nusselt number is obtained for triangular ribs of angel 60°and at Reynolds number of 60000 compared to the Nusselt number for the ribs of angel 90° and 45° and at same Reynolds number. The recirculation regions generated by the ribs corresponding to the velocity streamline show the largest recirculation region at triangular ribs of angle 60° which also provides the highest enhancement of heat transfer.
Abstract: Seasonal variability of nutrients concentration in the Baltic Sea using the 3D ecosystem numerical model 3D-CEMBS has been investigated. Additionally this study shows horizontal and vertical distribution of nutrients in the Baltic Sea. Model domain is an extended Baltic Sea area divided into 600x640 horizontal grid cells. Aside from standard hydrodynamic parameters 3D-CEMBS produces modeled ecological variables such as: three types of phytoplankton, two detrital classes, dissolved oxygen and the nutrients (nitrate, ammonium, phosphate and silicate). The presented model allows prediction of parameters that describe distribution of nutrients concentration and phytoplankton biomass. 3D-CEMBS can be used to study the effect of different hydrodynamic and biogeochemical processes on distributions of these variables in a larger scale.
Abstract: Some theoretical and experimental aspects related to
the conceptual analyses concerning the direct correspondence
identification between the shape, area and orientation of plantar
pressure and obtaining adequate corrective insoles by rapid
prototyping are presented in this paper. In the first part of the paper
there is the theoretical-correlative concept, which is the fundament of
correspondence deduction between plantar surface characteristics and
respectively corrective insoles. In the second part of the paper the
experimental equipment used to analyze and perform the
correspondence stages and then the integral ones between the
analyzed foot shapes and the ones with corrective insoles is
presented. In the final parte the results used to adapt the insoles
obtained by rapid prototyping but also some specific aspects and
conclusions of the conceptual analysis of direct and rapid
correspondence are shown.
Abstract: In this research, the researchers have managed to
design a model to investigate the current trend of stock price of the
"IRAN KHODRO corporation" at Tehran Stock Exchange by
utilizing an Adaptive Neuro - Fuzzy Inference system. For the Longterm
Period, a Neuro-Fuzzy with two Triangular membership
functions and four independent Variables including trade volume,
Dividend Per Share (DPS), Price to Earning Ratio (P/E), and also
closing Price and Stock Price fluctuation as an dependent variable are
selected as an optimal model. For the short-term Period, a neureo –
fuzzy model with two triangular membership functions for the first
quarter of a year, two trapezoidal membership functions for the
Second quarter of a year, two Gaussian combination membership
functions for the third quarter of a year and two trapezoidal
membership functions for the fourth quarter of a year were selected
as an optimal model for the stock price forecasting. In addition, three
independent variables including trade volume, price to earning ratio,
closing Stock Price and a dependent variable of stock price
fluctuation were selected as an optimal model. The findings of the
research demonstrate that the trend of stock price could be forecasted
with the lower level of error.
Abstract: The main purpose of the research is to address the role of psychological harassment behaviors (mobbing) to which employees are exposed and personality characteristics over work alienation. Research population was composed of the employees of Provincial Special Administration. A survey with four sections was created to measure variables and reach out the basic goals of the research. Correlation and step-wise regression analyses were performed to investigate the separate and overall effects of sub-dimensions of psychological harassment behaviors and personality characteristic on work alienation of employees. Correlation analysis revealed significant but weak relationships between work alienation and psychological harassment and personality characteristics. Step-wise regression analysis revealed also significant relationships between work alienation variable and assault to personality, direct negative behaviors (sub dimensions of mobbing) and openness (sub-dimension of personality characteristics). Each variable was introduced into the model step by step to investigate the effects of significant variables in explaining the variations in work alienation. While the explanation ratio of the first model was 13%, the last model including three variables had an explanation ratio of 24%.
Abstract: Many attempts have been made to strengthen Feistel based block ciphers. Among the successful proposals is the key- dependent S-box which was implemented in some of the high-profile ciphers. In this paper a key-dependent permutation box is proposed and implemented on DES as a case study. The new modified DES, MDES, was tested against Diehard Tests, avalanche test, and performance test. The results showed that in general MDES is more resistible to attacks than DES with negligible overhead. Therefore, it is believed that the proposed key-dependent permutation should be considered as a valuable primitive that can help strengthen the security of Substitution-Permutation Network which is a core design in many Feistel based block ciphers.
Abstract: The small interfering RNA (siRNA) alters the
regulatory role of mRNA during gene expression by translational
inhibition. Recent studies show that upregulation of mRNA because
serious diseases like cancer. So designing effective siRNA with good
knockdown effects plays an important role in gene silencing. Various
siRNA design tools had been developed earlier. In this work, we are
trying to analyze the existing good scoring second generation siRNA
predicting tools and to optimize the efficiency of siRNA prediction
by designing a computational model using Artificial Neural Network
and whole stacking energy (%G), which may help in gene silencing
and drug design in cancer therapy. Our model is trained and tested
against a large data set of siRNA sequences. Validation of our results
is done by finding correlation coefficient of experimental versus
observed inhibition efficacy of siRNA. We achieved a correlation
coefficient of 0.727 in our previous computational model and we
could improve the correlation coefficient up to 0.753 when the
threshold of whole tacking energy is greater than or equal to -32.5
kcal/mol.
Abstract: Unsteady natural convection and heat transfer in a square cavity partially filled with porous media using a thermal
non-equilibrium model is studied in this paper. The left vertical wall is
maintained at a constant hot temperature Th and the right vertical wall
is maintained at a constant cold temperature Tc, while the horizontal
walls are adiabatic. The governing equations are obtained by applying
the Darcy model and Boussinesq approximation. COMSOL’s finite
element method is used to solve the non-dimensional governing
equations together with specified boundary conditions. The governing
parameters of this study are the Rayleigh number (Ra = 10^5, and Ra = 10^6 ), Darcy namber (Da = 10^−2, and Da = 10^−3),
the modified thermal conductivity ratio (10^−1 ≤ γ ≤ 10^4), the inter-phase heat transfer coefficien (10^−1 ≤ H ≤ 10^3) and the
time dependent (0.001 ≤ τ ≤ 0.2). The results presented for
values of the governing parameters in terms of streamlines in both
fluid/porous-layer, isotherms of fluid in fluid/porous-layer, isotherms
of solid in porous layer, and average Nusselt number.
Abstract: The world wide web coupled with the ever-increasing
sophistication of online technologies and software applications puts
greater emphasis on the need of even more sophisticated and
consistent quality requirements modeling than traditional software
applications. Web sites and Web applications (WebApps) are
becoming more information driven and content-oriented raising the
concern about their information quality (InQ). The consistent and
consolidated modeling of InQ requirements for WebApps at different
stages of the life cycle still poses a challenge. This paper proposes an
approach to specify InQ requirements for WebApps by reusing and
extending the ISO 25012:2008(E) data quality model. We also
discuss learnability aspect of information quality for the WebApps.
The proposed ISO 25012 based InQ framework is a step towards a
standardized approach to evaluate WebApps InQ.
Abstract: The aim of this research is to develop the
understanding of corporate social responsibility (CSR) from
consumers- perspective toward Thai mobile service providers.
Based on the survey from 400 mobile customers, the result
shows that four dimensions of CSR of Thai mobile service
providers consist of economic, legal, ethical and philanthropic
responsibility. These four CSR factors have positive impacts
on enhancing customer satisfaction except one item of
economic responsibility - profitability to shareholders. Ethical
dimension has the strongest impact on customer satisfaction.
Economic, legal, ethical, philanthropic responsibility and
customer satisfaction have major impact on loyalty, whilst
philanthropic component mostly affects loyalty.
Abstract: As the performance of the filtering system depends
upon the accuracy of the noise detection scheme, in this paper, we
present a new scheme for impulse noise detection based on two
levels of decision. In this scheme in the first stage we coarsely
identify the corrupted pixels and in the second stage we finally
decide whether the pixel under consideration is really corrupt or not.
The efficacy of the proposed filter has been confirmed by extensive
simulations.
Abstract: The aim of this study was to develop a storm water quality improvement strategy plan (WQISP) which assists managers and decision makers of local city councils in enhancing their activities to improve regional water quality. City of Gosnells in Western Australia has been considered as a case study. The procedure on developing the WQISP consists of reviewing existing water quality data, identifying water quality issues in the study areas and developing a decision making tool for the officers, managers and decision makers. It was found that land use type is the main factor affecting the water quality. Therefore, activities, sources and pollutants related to different land use types including residential, industrial, agricultural and commercial are given high importance during the study. Semi-structured interviews were carried out with coordinators of different management sections of the regional councils in order to understand the associated management framework and issues. The issues identified from these interviews were used in preparing the decision making tool. Variables associated with the defined “value versus threat" decision making tool are obtained from the intensive literature review. The main recommendations provided for improvement of water quality in local city councils, include non-structural, structural and management controls and potential impacts of climate change.
Abstract: Location-aware computing is a type of pervasive
computing that utilizes user-s location as a dominant factor for
providing urban services and application-related usages. One of the
important urban services is navigation instruction for wayfinders in a
city especially when the user is a tourist. The services which are
presented to the tourists should provide adapted location aware
instructions. In order to achieve this goal, the main challenge is to
find spatial relevant objects and location-dependent information. The
aim of this paper is the development of a reusable location-aware
model to handle spatial relevancy parameters in urban location-aware
systems. In this way we utilized ontology as an approach which could
manage spatial relevancy by defining a generic model. Our
contribution is the introduction of an ontological model based on the
directed interval algebra principles. Indeed, it is assumed that the
basic elements of our ontology are the spatial intervals for the user
and his/her related contexts. The relationships between them would
model the spatial relevancy parameters. The implementation language
for the model is OWLs, a web ontology language. The achieved
results show that our proposed location-aware model and the
application adaptation strategies provide appropriate services for the
user.