Abstract: The problem of manipulator control is a highly
complex problem of controlling a system which is multi-input, multioutput,
non-linear and time variant. In this paper some adaptive
fuzzy, and a new hybrid fuzzy control algorithm have been
comparatively evaluated through simulations, for manipulator
control. The adaptive fuzzy controllers consist of self-organizing,
self-tuning, and coarse/fine adaptive fuzzy schemes. These
controllers are tested for different trajectories and for varying
manipulator parameters through simulations. Various performance
indices like the RMS error, steady state error and maximum error are
used for comparison. It is observed that the self-organizing fuzzy
controller gives the best performance. The proposed hybrid fuzzy
plus integral error controller also performs remarkably well, given its
simple structure.
Abstract: As a matter of the fact that online social networks like
Twitter, Facebook and MySpace have experienced an extensive
growth in recent years. Social media offers individuals with a tool for
communicating and interacting with one another. These social
networks enable people to stay in touch with other people and
express themselves. This process makes the users of online social
networks active creators of content rather than being only consumers
of traditional media. That’s why millions of people show strong
desire to learn the methods and tools of digital content production
and necessary communication skills. However, the booming interest
in communication and interaction through online social networks and
high level of eagerness to invent and implement the ways to
participate in content production raise some privacy and security
concerns.
This presentation aims to open the assumed revolutionary,
democratic and liberating nature of the online social media up for
discussion by reviewing some recent political developments in
Turkey. Firstly, the role of Internet and online social networks in
mobilizing collective movements through social interactions and
communications will be questioned. Secondly, some cases from Gezi
and Okmeydanı Protests and also December 17-25 period will be
presented in order to illustrate misinformation and manipulation in
social media and violation of individual privacy through online social
networks in order to damage social unity and stability contradictory
to democratic nature of online social networking.
Abstract: Due to their high power-to-weight ratio and low cost,
pneumatic actuators are attractive for robotics and automation
applications; however, achieving fast and accurate control of their
position have been known as a complex control problem. A
methodology for obtaining high position accuracy with a linear
pneumatic actuator is presented. During experimentation with a
number of PID classical control approaches over many operations of
the pneumatic system, the need for frequent manual re-tuning of the
controller could not be eliminated. The reason for this problem is
thermal and energy losses inside the cylinder body due to the
complex friction forces developed by the piston displacements.
Although PD controllers performed very well over short periods, it
was necessary in our research project to introduce some form of
automatic gain-scheduling to achieve good long-term performance.
We chose a fuzzy logic system to do this, which proved to be an
easily designed and robust approach. Since the PD approach showed
very good behaviour in terms of position accuracy and settling time,
it was incorporated into a modified form of the 1st order Tagaki-
Sugeno fuzzy method to build an overall controller. This fuzzy gainscheduler
uses an input variable which automatically changes the PD
gain values of the controller according to the frequency of repeated
system operations. Performance of the new controller was
significantly improved and the need for manual re-tuning was
eliminated without a decrease in performance. The performance of
the controller operating with the above method is going to be tested
through a high-speed web network (GRID) for research purposes.
Abstract: This paper deals with analysis of flexural stiffness,
indentation and their energies in three point loading of sandwich
beams with composite faces from Eglass/epoxy and cores from
Polyurethane or PVC. Energy is consumed in three stages of
indentation in laminated beam, indentation of sandwich beam and
bending of sandwich beam. Theory of elasticity is chosen to present
equations for indentation of laminated beam, then these equations
have been corrected to offer better results. An analytical model has
been used assuming an elastic-perfectly plastic compressive behavior
of the foam core. Classical theory of beam is used to describe three
point bending. Finite element (FE) analysis of static indentation
sandwich beams is performed using the FE code ABAQUS. The
foam core is modeled using the crushable foam material model and
response of the foam core is experimentally characterized in uniaxial
compression.
Three point bending and indentation have been done
experimentally in two cases of low velocity and higher velocity
(quasi-impact) of loading. Results can describe response of beam in
terms of core and faces thicknesses, core material, indentor diameter,
energy absorbed, and length of plastic area in the testing. The
experimental results are in good agreement with the analytical and
FE analyses. These results can be used as an introduction for impact
loading and energy absorbing of sandwich structures.
Abstract: In this study, Friction Stir Processing (FSP) a recent grain refinement technique was employed to disperse micron-sized (2 *m) SiCp particles into aluminum alloy AA6063. The feasibility to fabricate bulk composites through FSP was analyzed and experiments were conducted at different traverse speeds and wider volumes of the specimens. Micro structural observation were carried out by employing optical microscopy test of the cross sections in both parallel and perpendicular to the tool traverse direction. Mechanical property including micro hardness was evaluated in detail at various regions on the specimen. The composites had an excellent bonding with aluminum alloy substrate and a significant increase of 30% in the micro hardness value of metal matrix composite (MMC) as to that of the base metal has observed. The observations clearly indicate that SiC particles were uniformly distributed within the aluminum matrix.
Abstract: Pentachlorophenol (PCP) is a polychlorinated
aromatic compound that is widespread in industrial effluents and is
considered to be a serious pollutant. Among the variety of industrial
effluents encountered, effluents from tanning industry are very
important and have a serious pollution potential. PCP is also formed
unintentionally in effluents of paper and pulp industries. It is highly
persistent in soils and is lethal to a wide variety of beneficial
microorganisms and insects, human beings and animals. The natural
processes that breakdown toxic chemicals in the environment have
become the focus of much attention to develop safe and environmentfriendly
deactivation technologies. Microbes and plants are among
the most important biological agents that remove and degrade waste
materials to enable their recycling in the environment. The present
investigation was carried out with the aim of developing a microbial
system for bioremediation of PCP polluted soils. A number of plant
species were evaluated for their ability to tolerate different
concentrations of pentachlorophenol (PCP) in the soil. The
experiment was conducted for 30 days under pot culture conditions.
The toxic effect of PCP on plants was studied by monitoring seed
germination, plant growth and biomass. As the concentration of PCP
was increased to 50 ppm, the inhibition of seed germination, plant
growth and biomass was also increased. Although PCP had a
negative effect on all plant species tested, maize and groundnut
showed the maximum tolerance to PCP. Other tolerating crops
included wheat, safflower, sunflower, and soybean. From the
rhizosphere soil of the tolerant seedlings, as many as twenty seven
PCP tolerant bacteria were isolated. From soybean, 8; sunflower, 3;
safflower 8; maize 2; groundnut and wheat, 3 each isolates were
made. They were screened for their PCP degradation potentials.
HPLC analyses of PCP degradation revealed that the isolate MAZ-2
degraded PCP completely. The isolate MAZ-1 was the next best
isolate with 90 per cent PCP degradation. These strains hold promise
to be used in the bioremediation of PCP polluted soils.
Abstract: In this paper we present a new approach to detecting a
flaw in T.O.F.D (Time Of Flight Diffraction) type ultrasonic image
based on texture features. Texture is one of the most important
features used in recognizing patterns in an image. The paper
describes texture features based on 2D Gabor functions, i.e.,
Gaussian shaped band-pass filters, with dyadic treatment of the radial
spatial frequency range and multiple orientations, which represent an
appropriate choice for tasks requiring simultaneous measurement in
both space and frequency domains. The most relevant features are
used as input data on a Fuzzy c-mean clustering classifier. The
classes that exist are only two: 'defects' or 'no defects'. The proposed
approach is tested on the T.O.F.D image achieved at the laboratory
and on the industrial field.
Abstract: The new semi-experimental method for simulation of
the turbine flow meters rotation in the transitional flow has been
developed. The method is based on the experimentally established
exponential low of changing of dimensionless relative turbine gas
meter rotation frequency and meter inertia time constant. For
experimental evaluation of the meter time constant special facility
has been developed. The facility ensures instant switching of turbine
meter under test from one channel to the other channel with different
flow rate and measuring the meter response. The developed method
can be used for evaluation and predication of the turbine meters
response and dynamic error in the transitional flow with any arbitrary
law of flow rate changing. The examples of the method application
are presented.
Abstract: In this paper, a parametric experimental study for producing paving blocks using fine and coarse waste glass is presented. Some of the physical and mechanical properties of paving blocks having various levels of fine glass (FG) and coarse glass (CG) replacements with fine aggregate (FA) are investigated. The test results show that the replacement of FG by FA at level of 20% by weight has a significant effect on the compressive strength, flexural strength, splitting tensile strength and abrasion resistance of the paving blocks as compared with the control sample because of puzzolanic nature of FG. The compressive strength, flexural strength, splitting tensile strength and abrasion resistance of the paving block samples in the FG replacement level of 20% are 69%, 90%, 47% and 15 % higher as compared with the control sample respectively. It is reported in the earlier works the replacement of FG by FA at level of 20% by weight suppress the alkali-silica reaction (ASR) in the concrete. The test results show that the FG at level of 20% has a potential to be used in the production of paving blocks. The beneficial effect on these properties of CG replacement with FA is little as compared with FG.
Abstract: The stab resistance performance of newly developed
fabric composites composed of hexagonal paper honeycombs, filled
with shear thickening fluid (STF), and woven Kevlar® fabric or
UHMPE was investigated in this study. The STF was prepared by
dispersing submicron SiO2 particles into polyethylene glycol (PEG).
Our results indicate that the STF-Kevlar composite possessed lower
penetration depth than that of neat Kevlar. In other words, the
STF-Kevlar composite can attain the same energy level in
stab-resistance test with fewer layers of Kevlar fabrics than that of the
neat Kevlar fabrics. It also indicates that STF can be used for the
fabrication of flexible body armors and can provide improved
protection against stab threats. We found that the stab resistance of the
STF-Kevlar composite increases with the increase of SiO2
concentration in STF. Moreover, the silica particles functionalized
with silane coupling agent can further improve the stab resistance.
Abstract: This paper presents an approach which is based on the
use of supervised feed forward neural network, namely multilayer
perceptron (MLP) neural network and finite element method (FEM)
to solve the inverse problem of parameters identification. The
approach is used to identify unknown parameters of ferromagnetic
materials. The methodology used in this study consists in the
simulation of a large number of parameters in a material under test,
using the finite element method (FEM). Both variations in relative
magnetic permeability and electrical conductivity of the material
under test are considered. Then, the obtained results are used to
generate a set of vectors for the training of MLP neural network.
Finally, the obtained neural network is used to evaluate a group of
new materials, simulated by the FEM, but not belonging to the
original dataset. Noisy data, added to the probe measurements is used
to enhance the robustness of the method. The reached results
demonstrate the efficiency of the proposed approach, and encourage
future works on this subject.
Abstract: Chicken feathers were used as biosorbent for Pb
removal from aqueous solution. In this paper, the kinetics and
equilibrium studies at several pH, temperature, and metal
concentration values are reported. For tested conditions, the Pb
sorption capacity of this poultry waste ranged from 0.8 to 8.3 mg/g.
Optimal conditions for Pb removal by chicken feathers have been
identified. Pseudo-first order and pseudo-second order equations
were used to analyze the experimental data. In addition, the sorption
isotherms were fitted to classical Langmuir and Freundlich models.
Finally, thermodynamic parameters for the sorption process have
been determined. In summary, the results showed that chicken
feathers are an alternative and promising sorbent for the treatment of
effluents polluted by Pb ions.
Abstract: The accomplished study is based on the appointment
and identification of ageing effects and according to this absorption
of moisture of aircraft cabin components over the life-cycle. In the
first step of the study ceiling panels from same age and from the
same aircraft cabin have been examined according to weight changes
depending on the position in the aircraft cabin. In the second step of
the study different aged ceiling panels have been examined
concerning deflection, weight changes and the acoustic sound
transmission loss. To prove the assumption of water absorption
within the study and with the theoretical background from literature
and scientific papers, an older test panel was exposed extreme
thermal conditions (humidity and temperature) within a climate
chamber to show that there is a general ingress of water to cabin
components and that this ingress of water leads to the change of
different mechanical properties.
Abstract: For complete support of Quality of Service, it is better that environment itself predicts resource requirements of a job by using special methods in the Grid computing. The exact and correct prediction causes exact matching of required resources with available resources. After the execution of each job, the used resources will be saved in the active database named "History". At first some of the attributes will be exploit from the main job and according to a defined similarity algorithm the most similar executed job will be exploited from "History" using statistic terms such as linear regression or average, resource requirements will be predicted. The new idea in this research is based on active database and centralized history maintenance. Implementation and testing of the proposed architecture results in accuracy percentage of 96.68% to predict CPU usage of jobs and 91.29% of memory usage and 89.80% of the band width usage.
Abstract: This study was conducted to evaluate the antifungal
activities of Cinnamomum zeylanicum and Origanum vulgare L.
essential oil against Aspergillus flavus in culture media and tomato
paste. 200 ppm of cinnamon and 500 ppm of oregano completely
inhibited A. flavus growth in culture media, while in tomato paste 300
ppm of cinnamon and 200 ppm of oregano had the same effect. Test
panel evaluations revealed that samples with 100 and 200 ppm
cinnamon were acceptable. The results may suggest the potential use
of Cinnamomum zeylanicum essential oil as natural preservative in
tomato paste.
Abstract: The present study aims at determining the effect of ageing on the impact toughness and microstructure of 2024 Al-Cu - Mg alloy. Following the 2 h solutionizing treatment at 450°C and water quench, the specimens were aged at 200°C for various periods (1 to 18 h). The precipitation stages during ageing were monitored by hardness measurements. For each specimen group, Charpy impact and hardness tests were carried out. During ageing the impact toughness of the alloy first increased, and then, following a maxima decreased due to the precipitation of intermediate phases, finally it reached its minimum at the peak hardness. Correlations between hardness and impact toughness were investigated.
Abstract: Stair climbing is one of critical issues for field robots to
widen applicable areas. This paper presents optimal design on
kinematic parameters of a new robotic platform for stair climbing. The
robotic platform climbs various stairs by body flip locomotion with
caterpillar type main platform. Kinematic parameters such as platform
length, platform height, and caterpillar rotation speed are optimized to
maximize stair climbing stability. Three types of stairs are used to
simulate typical user conditions. The optimal design process is
conducted based on Taguchi methodology, and resulting parameters
with optimized objective function are presented. In near future, a
prototype is assembled for real environment testing.
Abstract: Web applications have become complex and crucial for many firms, especially when combined with areas such as CRM (Customer Relationship Management) and BPR (Business Process Reengineering). The scientific community has focused attention to Web application design, development, analysis, testing, by studying and proposing methodologies and tools. Static and dynamic techniques may be used to analyze existing Web applications. The use of traditional static source code analysis may be very difficult, for the presence of dynamically generated code, and for the multi-language nature of the Web. Dynamic analysis may be useful, but it has an intrinsic limitation, the low number of program executions used to extract information. Our reverse engineering analysis, used into our WAAT (Web Applications Analysis and Testing) project, applies mutational techniques in order to exploit server side execution engines to accomplish part of the dynamic analysis. This paper studies the effects of mutation source code analysis applied to Web software to build application models. Mutation-based generated models may contain more information then necessary, so we need a pruning mechanism.
Abstract: This paper presents a critical study about the
application of Neural Networks to ion-exchange process. Ionexchange
is a complex non-linear process involving many factors
influencing the ions uptake mechanisms from the pregnant solution.
The following step includes the elution. Published data presents
empirical isotherm equations with definite shortcomings resulting in
unreliable predictions. Although Neural Network simulation
technique encounters a number of disadvantages including its “black
box", and a limited ability to explicitly identify possible causal
relationships, it has the advantage to implicitly handle complex
nonlinear relationships between dependent and independent
variables. In the present paper, the Neural Network model based on
the back-propagation algorithm Levenberg-Marquardt was developed
using a three layer approach with a tangent sigmoid transfer function
(tansig) at hidden layer with 11 neurons and linear transfer function
(purelin) at out layer. The above mentioned approach has been used
to test the effectiveness in simulating ion exchange processes. The
modeling results showed that there is an excellent agreement between
the experimental data and the predicted values of copper ions
removed from aqueous solutions.
Abstract: Environmental awareness and the recent
environmental policies have forced many electric utilities to
restructure their operational practices to account for their emission
impacts. One way to accomplish this is by reformulating the
traditional economic dispatch problem such that emission effects are
included in the mathematical model. This paper presents a Particle
Swarm Optimization (PSO) algorithm to solve the Economic-
Emission Dispatch problem (EED) which gained recent attention due
to the deregulation of the power industry and strict environmental
regulations. The problem is formulated as a multi-objective one with
two competing functions, namely economic cost and emission
functions, subject to different constraints. The inequality constraints
considered are the generating unit capacity limits while the equality
constraint is generation-demand balance. A novel equality constraint
handling mechanism is proposed in this paper. PSO algorithm is
tested on a 30-bus standard test system. Results obtained show that
PSO algorithm has a great potential in handling multi-objective
optimization problems and is capable of capturing Pareto optimal
solution set under different loading conditions.