Abstract: An effect of rolling temperature on the mechanical properties and microstructural evolution of an Al-Mg-Si alloy was studied. The material was rolled up to a true strain of ~0.7 at three different temperatures viz; room temperature, liquid propanol and liquid nitrogen. The liquid nitrogen rolled sample exhibited superior properties with a yield and tensile strength of 332 MPa and 364 MPa, respectively, with a reasonably good ductility of ~9%. The liquid nitrogen rolled sample showed around 54 MPa increase in tensile strength without much reduction in the ductility as compared to the as received T6 condition alloy. The microstructural details revealed equiaxed grains in the annealed and solutionized sample and elongated grains in the rolled samples. In addition, the cryorolled samples exhibited fine grain structure compared to the room temperature rolled samples.
Abstract: ZnS nanoparticles of different size have been
synthesized using a colloidal particles method. Zns nanoparticles
prepared with capping agent (mercaptoethanol) then were
characterized using X-ray diffraction (XRD) and UV-Vis
spectroscopy. The particle size of the nanoparticles calculated from
the XRD patterns has been found in the range 1.85-2.44nm.
Absorption spectra have been obtained using UV-Vis
spectrophotometer to find the optical band gap and the obtained
values have been founded to being range 3.83-4.59eV. It was also
found that energy band gap increase with the increase in molar
capping agent solution.
Abstract: This paper present a new method for design of power
system stabilizer (PSS) based on sliding mode control (SMC)
technique. The control objective is to enhance stability and improve
the dynamic response of the multi-machine power system. In order to
test effectiveness of the proposed scheme, simulation will be carried
out to analyze the small signal stability characteristics of the system
about the steady state operating condition following the change in
reference mechanical torque and also parameters uncertainties. For
comparison, simulation of a conventional control PSS (lead-lag
compensation type) will be carried out. The main approach is
focusing on the control performance which later proven to have the
degree of shorter reaching time and lower spike.
Abstract: The requirements analysis, modeling, and simulation have consistently been one of the main challenges during the development of complex systems. The scenarios and the state machines are two successful models to describe the behavior of an interactive system. The scenarios represent examples of system execution in the form of sequences of messages exchanged between objects and are a partial view of the system. In contrast, state machines can represent the overall system behavior. The automation of processing scenarios in the state machines provide some answers to various problems such as system behavior validation and scenarios consistency checking. In this paper, we propose a method for translating scenarios in state machines represented by Discreet EVent Specification and procedure to detect implied scenarios. Each induced DEVS model represents the behavior of an object of the system. The global system behavior is described by coupling the atomic DEVS models and validated through simulation. We improve the validation process with integrating formal methods to eliminate logical inconsistencies in the global model. For that end, we use the Z notation.
Abstract: Open urban public spaces comprise an important
element for the development of social, cultural and economic
activities of the population in the modern cities. These spaces are also
considered regulators of the region-s climate conditions, providing
better thermal, visual and auditory conditions which can be optimized
by the application of appropriate strategies of bioclimatic design. The
paper focuses on the analysis and evaluation of the recent unification
of the open spaces in the centre of Xanthi, a medium – size city in
northern Greece, from a bioclimatic perspective, as well as in the
creation of suitable methodology. It is based both on qualitative
observation of the interventions by fieldwork research and
assessment and on quantitative analysis and modeling of the research
area.
Abstract: The Expert Witness Testimony in the Battered
Woman Syndrome Expert witness testimony (EWT) is a kind of
information given by an expert specialized in the field (here in BWS)
to the jury in order to help the court better understand the case. EWT
does not always work in favor of the battered women. Two main
decision-making models are discussed in the paper: the Mathematical
model and the Explanation model. In the first model, the jurors
calculate ″the importance and strength of each piece of evidence″
whereas in the second model they try to integrate the EWT with the
evidence and create a coherent story that would describe the crime.
The jury often misunderstands and misjudges battered women for
their action (or in this case inaction). They assume that these women
are masochists and accept being mistreated for if a man abuses a
woman constantly, she should and could divorce him or simply leave
at any time. The research in the domain found that indeed, expert
witness testimony has a powerful influence on juror’s decisions thus
its quality needs to be further explored. One of the important factors
that need further studies is a bias called the dispositionist worldview
(a belief that what happens to people is of their own doing). This
kind of attributional bias represents a tendency to think that a
person’s behavior is due to his or her disposition, even when the
behavior is clearly attributed to the situation. Hypothesis The
hypothesis of this paper is that if a juror has a dispositionist
worldview then he or she will blame the rape victim for triggering the
assault. The juror would therefore commit the fundamental
attribution error and believe that the victim’s disposition caused the
rape and not the situation she was in. Methods The subjects in the
study were 500 randomly sampled undergraduate students from
McGill, Concordia, Université de Montréal and UQAM.
Dispositional Worldview was scored on the Dispositionist
Worldview Questionnaire. After reading the Rape Scenarios, each
student was asked to play the role of a juror and answer a
questionnaire consisting of 7 questions about the responsibility,
causality and fault of the victim. Results The results confirm the
hypothesis which states that if a juror has a dispositionist worldview
then he or she will blame the rape victim for triggering the assault.
By doing so, the juror commits the fundamental attribution error
because he will believe that the victim’s disposition, and not the
constraints or opportunities of the situation, caused the rape scenario.
Abstract: Estimation of stormwater pollutants is a pre-requisite
for the protection and improvement of the aquatic environment and
for appropriate management options. The usual practice for the
stormwater quality prediction is performed through water quality
modeling. However, the accuracy of the prediction by the models
depends on the proper estimation of model parameters. This paper
presents the estimation of model parameters for a catchment water
quality model developed for the continuous simulation of stormwater
pollutants from a catchment to the catchment outlet. The model is
capable of simulating the accumulation and transportation of the
stormwater pollutants; suspended solids (SS), total nitrogen (TN) and
total phosphorus (TP) from a particular catchment. Rainfall and water
quality data were collected for the Hotham Creek Catchment (HTCC),
Gold Coast, Australia. Runoff calculations from the developed model
were compared with the calculated discharges from the widely used
hydrological models, WBNM and DRAINS. Based on the measured
water quality data, model water quality parameters were calibrated
for the above-mentioned catchment. The calibrated parameters are
expected to be helpful for the best management practices (BMPs)
of the region. Sensitivity analyses of the estimated parameters were
performed to assess the impacts of the model parameters on overall
model estimations of runoff water quality.
Abstract: This paper proposes a novel architecture for At-
Home medical care which enables senior citizens, patients
with chronic ailments and patients requiring post- operative
care to be remotely monitored in the comfort of their homes.
This architecture is implemented using sensors and wireless
networking for transmitting patient data to the hospitals,
health- care centers for monitoring by medical professionals.
Patients are equipped with sensors to measure their
physiological parameters, like blood pressure, pulse rate etc.
and a Wearable Data Acquisition Unit is used to transmit the
patient sensor data. Medical professionals can be alerted to
any abnormal variations in these values for diagnosis and
suitable treatment. Security threats and challenges inherent to
wireless communication and sensor network have been
discussed and a security mechanism to ensure data
confidentiality and source authentication has been proposed.
Symmetric key algorithm AES has been used for encrypting
the data and a patent-free, two-pass block cipher mode CCFB
has been used for implementing semantic security.
Abstract: This research is intended to develop a raw material allocation model in timber processing industry in Perum Perhutani Unit I, Central Java, Indonesia. The model can be used to determine the quantity of allocation of timber between chain in the supply chain to select supplier considering factors that are log price and the distance. In determining the quantity of allocation of timber between chains in the supply chain, the model considers the optimal inventory in each chain. Whilst the optimal inventory is determined based on demand forecast, the capacity and safety stock. Problem solving allocation is conducted by developing linear programming model that aims to minimize the total cost of the purchase, transportation cost and storage costs at each chain. The results of numerical examples show that the proposed model can generate savings of the purchase cost of 20.84% and select suppliers with mileage closer.
Abstract: The present paper reports results of an experimental
program conducted to study performance of fly ash based
geopolymer pastes at elevated temperature. Three series of
geopolymer pastes differing in Na2O content (8.5%, 10% and 11.5%)
were manufactured by activating low calcium fly ash with a mixture
of sodium hydroxide and sodium silicate solution. The paste
specimens were subjected to temperatures as high as 900oC and the
behaviour at elevated temperatures were investigated on the basis of
physical appearance, weight losses, residual strength, shrinkage
measurements and sorptivity tests at different temperatures. Scanning
electron microscopy along with EDX and XRD tests were also
conducted to examine microstructure and mineralogical changes
during the thermal exposure. Specimens which were initially grey
turned reddish accompanied by appearance of small cracks as the
temperature increased to 900oC. Loss of weight was more in
specimens manufactured with highest Na2O content. Geopolymer
paste specimen containing minimum Na2O performed better than
those with higher Na2O content in terms of residual compressive
strength.
Abstract: In contrast to existing of calculation of temperature field of a profile part a blade with convective cooling which are not taking into account multi connective in a broad sense of this term, we develop mathematical models and highly effective combination (BIEM AND FDM) numerical methods from the point of view of a realization on the PC. The theoretical substantiation of these methods is proved by the appropriate theorems.
Abstract: This study was carried out to evaluate concentration
of micro minerals (Zn, Fe, Mn, Cu and Se) of forages and their
distribution in fiber fraction (neutral detergent fiber/NDF and acid
detergent fiber/ADF) in South Sumatra during dry and rainy seasons.
Seven species of commonly forages namely Axonopus compressus,
Panicum maximum, Pennisetum purpuphoides, Leucaena
leucocephala, Centrocema pubescens, Calopogonium mucunoides
and Acacia mangium were collected at native pasture during rainy
and dry seasons. The results showed that micro minerals
concentration of forages and their distribution in fiber fraction varied
among species and season. In general, concentration of micro
minerals was slightly higher in rainy season compared to dry season
either in grass or legumes forages. In grass, concentration of Fe and
Mn were above the critical level, while 33.3 %, 100 % and 16.7 % of
evaluated grass were deficient in Zn, Cu and Se. Data on legume
forages show that 75 % of legumes were deficient in Zn and Mn, 62.5
% deficient in Cu and 50 % deficient in Se. There was no species of
legume deficient in Fe. Distribution of micro minerals in NDF and
ADF were also significantly affected by species and season and
depends on the kinds of element measured. Generally, micro minerals
were associated in fiber fractions much higher during dry season
compared to rainy season. Iron (Fe) and selenium (Se) in forages
were the highest elements associated in NDF and ADF, while the
lowest was found in Copper (Cu).
Abstract: Two seperate experiments by barley and alfalfa were
conducted to a 2×8 factorial completely randomised design, with four
replicates. Factors were inoculation (M) with Gomus mosseae or uninoculation
(M0) and seven levels of contaminants (Co, Cd, Pb and
combinations) plus an uncontaminated control treatment (C). Heavy
metals in plant tissues and soil were quantified by Inductively
Coupled Plasma Optical Emission Spectrometer (ICP-OES) (Variant-
Liberty 150AX Turbo). Phytoextraction coefficient of contaminants
calculated by concentration of heavy metals in the shoot (mgkg-1) /
concentration of heavy metals in soil (mgkg-1). In the barley, the
highest rate of phytoextraction coefficient of Pb, Cd and Co was in
M0Pb, M0PbCoCd and MCo, respectively (P
Abstract: Reinforced concrete stair slabs with mid landings i.e.
Dog-legged shaped are conventionally designed as per specifications
of standard codes of practices which guide about the effective span
according to the varying support conditions. Presently, the behavior
of such slabs has been investigated using Finite Element method. A
single flight stair slab with landings on both sides and supported at
ends on wall, and a multi flight stair slab with landings and six
different support arrangements have been analyzed. The results
obtained for stresses, strains and deflections are used to describe the
behavior of such stair slabs, including locations of critical moments
and deflections. Values of critical moments obtained by F.E. analysis
have also have been compared with that obtained from conventional
analysis. Analytical results show that the moments are also critical
near the kinks i.e. junction of mid-landing and inclined waist slab.
This change in the behavior of dog-legged stair slab may be due to
continuity of the material in transverse direction in two landings
adjoining the waist slab, hence additional stiffness achieved. This
change in the behavior is generally not taken care of in conventional
method of design.
Abstract: Face Recognition is a field of multidimensional
applications. A lot of work has been done, extensively on the most of
details related to face recognition. This idea of face recognition using
PCA is one of them. In this paper the PCA features for Feature
extraction are used and matching is done for the face under
consideration with the test image using Eigen face coefficients. The
crux of the work lies in optimizing Euclidean distance and paving the
way to test the same algorithm using Matlab which is an efficient tool
having powerful user interface along with simplicity in representing
complex images.
Abstract: Although achieving zero-defect software release is
practically impossible, software industries should take maximum
care to detect defects/bugs well ahead in time allowing only bare
minimums to creep into released version. This is a clear indicator of
time playing an important role in the bug detection. In addition to
this, software quality is the major factor in software engineering
process. Moreover, early detection can be achieved only through
static code analysis as opposed to conventional testing.
BugCatcher.Net is a static analysis tool, which detects bugs in .NET®
languages through MSIL (Microsoft Intermediate Language)
inspection. The tool utilizes a Parser based on Finite State Automata
to carry out bug detection. After being detected, bugs need to be
corrected immediately. BugCatcher.Net facilitates correction, by
proposing a corrective solution for reported warnings/bugs to end
users with minimum side effects. Moreover, the tool is also capable
of analyzing the bug trend of a program under inspection.
Abstract: Designing modern machine tools is a complex task. A
simulation tool to aid the design work, a virtual machine, has
therefore been developed in earlier work. The virtual machine
considers the interaction between the mechanics of the machine
(including structural flexibility) and the control system. This paper
exemplifies the usefulness of the virtual machine as a tool for product
development. An optimisation study is conducted aiming at
improving the existing design of a machine tool regarding weight and
manufacturing accuracy at maintained manufacturing speed. The
problem can be categorised as constrained multidisciplinary multiobjective
multivariable optimisation. Parameters of the control and
geometric quantities of the machine are used as design variables. This
results in a mix of continuous and discrete variables and an
optimisation approach using a genetic algorithm is therefore
deployed. The accuracy objective is evaluated according to
international standards. The complete systems model shows nondeterministic
behaviour. A strategy to handle this based on statistical
analysis is suggested. The weight of the main moving parts is reduced
by more than 30 per cent and the manufacturing accuracy is
improvement by more than 60 per cent compared to the original
design, with no reduction in manufacturing speed. It is also shown
that interaction effects exist between the mechanics and the control,
i.e. this improvement would most likely not been possible with a
conventional sequential design approach within the same time, cost
and general resource frame. This indicates the potential of the virtual
machine concept for contributing to improved efficiency of both
complex products and the development process for such products.
Companies incorporating such advanced simulation tools in their
product development could thus improve its own competitiveness as
well as contribute to improved resource efficiency of society at large.
Abstract: This paper uses the radial basis function neural
network (RBFNN) for system identification of nonlinear systems.
Five nonlinear systems are used to examine the activity of RBFNN in
system modeling of nonlinear systems; the five nonlinear systems are
dual tank system, single tank system, DC motor system, and two
academic models. The feed forward method is considered in this
work for modelling the non-linear dynamic models, where the KMeans
clustering algorithm used in this paper to select the centers of
radial basis function network, because it is reliable, offers fast
convergence and can handle large data sets. The least mean square
method is used to adjust the weights to the output layer, and
Euclidean distance method used to measure the width of the Gaussian
function.
Abstract: Biochemical investigations were carried out to assess
the effect of different exposure regimes of Kazakhstan crude oil
(KCO) on hepatic antioxidant defense system in albino rats.
Contaminants were delivered under two different dosing regimes,
with all treatments receiving the same total contaminant load by the
end of the exposure period. Rats in regime A injected with KCO
once at a dose of 6 ml/kg bw while in regime B injected multiply at a
dose of 1.5 ml/kg bw on day 1, 3, 5 and 8. Antioxidant biomarkers
were measured in hepatic tissue after 1, 3, 5 and 8 days. Significant
induction was observed in serum aminotransferases (ALT, AST)
(p
Abstract: In this paper, the strength of a stabilizer is determined when the static and fatigue multiaxial loading are applied. Stabilizer is a part of suspension system in the heavy truck for stabilizing the cabin against the vibration of the road which composes of a thin-walled tube joined to a forge component by fillet weld. The component is loaded by non proportional random sequence of torsion and bending. Residual stress of welding process is considered here for static loading. This static loading with road irregularities are applied in this study as fatigue case that can affected in the fillet welded area of this part. The stresses in the welded structure are calculated using FEA. In addition, the fatigue with multi axial loading in the fillet weld is also investigated and the critical zone of the stabilizer is specified and presented by graphs. Residual stresses that have been resulted by the thermal forces are considered in FEA. Force increasing is the element of finding the critical point of the component.