Abstract: Typical load-bearing biological materials like bone,
mineralized tendon and shell, are biocomposites made from both
organic (collagen) and inorganic (biomineral) materials. This
amazing class of materials with intrinsic internally designed
hierarchical structures show superior mechanical properties with
regard to their weak components from which they are formed.
Extensive investigations concentrating on static loading conditions
have been done to study the biological materials failure. However,
most of the damage and failure mechanisms in load-bearing
biological materials will occur whenever their structures are exposed
to dynamic loading conditions. The main question needed to be
answered here is: What is the relation between the layout and
architecture of the load-bearing biological materials and their
dynamic behavior? In this work, a staggered model has been
developed based on the structure of natural materials at nanoscale and
Finite Element Analysis (FEA) has been used to study the dynamic
behavior of the structure of load-bearing biological materials to
answer why the staggered arrangement has been selected by nature to
make the nanocomposite structure of most of the biological materials.
The results showed that the staggered structures will efficiently
attenuate the stress wave rather than the layered structure.
Furthermore, such staggered architecture is effectively in charge of
utilizing the capacity of the biostructure to resist both normal and
shear loads. In this work, the geometrical parameters of the model
like the thickness and aspect ratio of the mineral inclusions selected
from the typical range of the experimentally observed feature sizes
and layout dimensions of the biological materials such as bone and
mineralized tendon. Furthermore, the numerical results validated with
existing theoretical solutions. Findings of the present work emphasize
on the significant effects of dynamic behavior on the natural
evolution of load-bearing biological materials and can help scientists
to design bioinspired materials in the laboratories.
Abstract: A robust sequential nonparametric method is proposed
for adaptation to background noise parameters for real-time. The
distribution of background noise was modelled like to Huber
contamination mixture. The method is designed to operate as an
adaptation-unit, which is included inside a detection subsystem of an
integrated multichannel monitoring system. The proposed method
guarantees the given size of a nonasymptotic confidence set for noise
parameters. Properties of the suggested method are rigorously
proved. The proposed algorithm has been successfully tested in real
conditions of a functioning C-OTDR monitoring system, which was
designed to monitor railways.
Abstract: Ceramic Waste Aggregates (CWAs) were made from
electric porcelain insulator wastes supplied from an electric power
company, which were crushed and ground to fine aggregate sizes. In
this study, to develop the CWA mortar as an eco–efficient, ground
granulated blast–furnace slag (GGBS) as a Supplementary
Cementitious Material (SCM) was incorporated. The water–to–binder
ratio (W/B) of the CWA mortars was varied at 0.4, 0.5, and 0.6. The
cement of the CWA mortar was replaced by GGBS at 20 and 40% by
volume (at about 18 and 37% by weight). Mechanical properties of
compressive and splitting tensile strengths, and elastic modulus were
evaluated at the age of 7, 28, and 91 days. Moreover, the chloride
ingress test was carried out on the CWA mortars in a 5.0% NaCl
solution for 48 weeks. The chloride diffusion was assessed by using an
electron probe microanalysis (EPMA). To consider the relation of the
apparent chloride diffusion coefficient and the pore size, the pore size
distribution test was also performed using a mercury intrusion
porosimetry at the same time with the EPMA. The compressive
strength of the CWA mortars with the GGBS was higher than that
without the GGBS at the age of 28 and 91 days. The resistance to the
chloride ingress of the CWA mortar was effective in proportion to the
GGBS replacement level.
Abstract: In developing countries, one of the most important
restrictions about the economic growth is the lack of national savings
which are supposed to finance the investments. In order to overcome
this restriction and achieve the higher rate of economic growth by
increasing the level of output, countries choose the external
borrowing. However, there is a dispute in the literature over the
correlation between external debt and economic growth. The aim of
this study is to examine the effects of external debt on Turkish
economic growth by using VAR analysis with the quarterly data over
the period of 2002:01-2014:04. In this respect, Johansen
Cointegration Test, Impulse- Response Function and Variance
Decomposition Tests will be used for analyses. Empirical findings
show that there is no cointegration in the long run.
Abstract: Live video streaming is one of the most widely used
service among end users, yet it is a big challenge for the network
operators in terms of quality. The only way to provide excellent
Quality of Experience (QoE) to the end users is continuous
monitoring of live video streaming. For this purpose, there are several
objective algorithms available that monitor the quality of the video in
a live stream. Subjective tests play a very important role in fine
tuning the results of objective algorithms. As human perception is
considered to be the most reliable source for assessing the quality of a
video stream subjective tests are conducted in order to develop more
reliable objective algorithms. Temporal impairments in a live video
stream can have a negative impact on the end users. In this paper we
have conducted subjective evaluation tests on a set of video
sequences containing temporal impairment known as frame freezing.
Frame Freezing is considered as a transmission error as well as a
hardware error which can result in loss of video frames on the
reception side of a transmission system. In our subjective tests, we
have performed tests on videos that contain a single freezing event
and also for videos that contain multiple freezing events. We have
recorded our subjective test results for all the videos in order to give a
comparison on the available No Reference (NR) objective
algorithms. Finally, we have shown the performance of no reference
algorithms used for objective evaluation of videos and suggested the
algorithm that works better. The outcome of this study shows the
importance of QoE and its effect on human perception. The results
for the subjective evaluation can serve the purpose for validating
objective algorithms.
Abstract: In this paper, we consider a cognitive relay network
(CRN) in which the primary receiver (PR) is protected by peak
transmit power ¯PST and/or peak interference power Q constraints.
In addition, the interference effect from the primary transmitter (PT)
is considered to show its impact on the performance of the CRN. We
investigate the outage probability (OP) and outage capacity (OC) of
the CRN by deriving closed-form expressions over Rayleigh fading
channel. Results show that both the OP and OC improve by increasing
the cooperative relay nodes as well as when the PT is far away from
the SR.
Abstract: Multiple User Interference (MUI) considers the
primary problem in Optical Code-Division Multiple Access
(OCDMA), which resulting from the overlapping among the users. In
this article we aim to mitigate this problem by studying an
interference cancellation scheme called successive interference
cancellation (SIC) scheme. This scheme will be tested on two
different detection schemes, spectral amplitude coding (SAC) and
direct detection systems (DS), using partial modified prime (PMP) as
the signature codes. It was found that SIC scheme based on both SAC
and DS methods had a potential to suppress the intensity noise, that is
to say it can mitigate MUI noise. Furthermore, SIC/DS scheme
showed much lower bit error rate (BER) performance relative to
SIC/SAC scheme for different magnitude of effective power. Hence,
many more users can be supported by SIC/DS receiver system.
Abstract: In recent years, fire accidents have been steadily
increased and the amount of property damage caused by the accidents
has gradually raised. Damaging building structure, fire incidents bring
about not only such property damage but also strength degradation and
member deformation. As a result, the building structure undermines its
structural ability. Examining the degradation and the deformation is
very important because reusing the building is more economical than
reconstruction. Therefore, engineers need to investigate the strength
degradation and member deformation well, and make sure that they
apply right rehabilitation methods. This study aims at evaluating
deformation characteristics of fire damaged and rehabilitated normal
strength concrete beams through both experiments and finite element
analyses. For the experiments, control beams, fire damaged beams and
rehabilitated beams are tested to examine deformation characteristics.
Ten test beam specimens with compressive strength of 21MPa are
fabricated and main test variables are selected as cover thickness of
40mm and 50mm and fire exposure time of 1 hour or 2 hours. After
heating, fire damaged beams are air-recurred for 2 months and
rehabilitated beams are repaired with polymeric cement mortar after
being removed the fire damaged concrete cover. All beam specimens
are tested under four points loading. FE analyses are executed to
investigate the effects of main parameters applied to experimental
study. Test results show that both maximum load and stiffness of the
rehabilitated beams are higher than those of the fire damaged beams.
In addition, predicted structural behaviors from the analyses also show
good rehabilitation effect and the predicted load-deflection curves are
similar to the experimental results. For the further, the proposed
analytical method can be used to predict deformation characteristics of
fire damaged and rehabilitated concrete beams without suffering from
time and cost consuming of experimental process.
Abstract: Transparent nickel doped cobalt sulfide was fabricated
on a SnO2:F electrode and tested as an efficient electrocatalyst and as
an alternative to the expensive platinum counter electrode. In order to
investigate how this electrode could affect the electrical
characteristics of a dye-sensitized solar cell, we manufactured cells
with the same TiO2 photoanode sensitized with dye (N719) and
employing the same quasi-solid electrolyte, altering only the counter
electrode used. The cells were electrically and electrochemically
characterized and it was observed that the ones with the Ni doped
CoS2 outperformed the efficiency of the cells with the Pt counter
electrode (3.76% and 3.44% respectively). Particularly, the higher
efficiency of the cells with the Ni doped CoS2 counter electrode (CE)
is mainly because of the enhanced photocurrent density which is
attributed to the enhanced electrocatalytic ability of the CE and the
low charge transfer resistance at the CE/electrolyte interface.
Abstract: This contribution presents a friction estimator for
industrial purposes which identifies Coulomb friction in a steering
system. The estimator only needs a few, usually known, steering
system parameters. Friction occurs on almost every mechanical
system and has a negative influence on high-precision position
control. This is demonstrated on a steering angle controller for highly
automated driving. In this steering system the friction induces limit
cycles which cause oscillating vehicle movement when the vehicle
follows a given reference trajectory. When compensating the friction
with the introduced estimator, limit cycles can be suppressed. This
is demonstrated by measurements in a series vehicle.
Abstract: Psychopathic disorders are taking an important part in
judge sentencing, especially in Canada. First, we will see how this
phenomenon can be illustrated by the high proportion of psychopath
offenders incarcerated in North American prisons. Many decisions in
Canadians courtrooms seem to point out that psychopathy is often
used as a strong argument by the judges to preserve public safety.
The fact that psychopathy is often associated with violence,
recklessness and recidivism, could explain why many judges consider
psychopathic disorders as an aggravating factor. Generally, the judge
reasoning is based on Article 753 of Canadian Criminal Code related
to dangerous offenders, which is used for individuals who show a
pattern of repetitive and persistent aggressive behaviour. Then we
will show how, with cognitive neurosciences, the psychopath’s
situation in courtrooms would probably change. Cerebral imaging
and news data provided by the neurosciences show that emotional
and volitional functions in psychopath’s brains are impaired.
Understanding these new issues could enable some judges to
recognize psychopathic disorders as a mitigating factor. Finally, two
important questions ought to be raised in this article: can exploring
psychopaths ‘brains really change the judge sentencing in Canadian
courtrooms? If yes, can judges consider psychopathy more as a
mitigating factor than an aggravating factor?
Abstract: The design of high pressure water jet based polishing
equipment and its fabrication conducted in this study is reported
herein, together with some preliminary test results for assessing its
applicability for HMA surface polishing. This study also provides
preliminary findings concerning the test variables, such as the
rotational speed, the water jet pressure, the abrasive agent used, and
the impact angel that were experimentally investigated in this study. The preliminary findings based on four trial tests (two on large
slab specimens and two on small size gyratory compacted
specimens), however, indicate that both friction and texture values
tend to increase with the polishing durations for two combinations of
pressure and rotation speed of the rotary deck. It seems that the more
polishing action the specimen is subjected to; the aggregate edges are
created such that the surface texture values are increased with the
accompanied increase in friction values. It may be of interest (but
which is outside the scope of this study) to investigate if the similar
trend exist for HMA prepared with aggregate source that is sand and
gravel.
Abstract: The quantitative study of cell mechanics is of
paramount interest, since it regulates the behaviour of the living cells
in response to the myriad of extracellular and intracellular
mechanical stimuli. The novel experimental techniques together with
robust computational approaches have given rise to new theories and
models, which describe cell mechanics as combination of
biomechanical and biochemical processes. This review paper
encapsulates the existing continuum-based computational approaches
that have been developed for interpreting the mechanical responses of
living cells under different loading and boundary conditions. The
salient features and drawbacks of each model are discussed from both
structural and biological points of view. This discussion can
contribute to the development of even more precise and realistic
computational models of cell mechanics based on continuum
approaches or on their combination with microstructural approaches,
which in turn may provide a better understanding of
mechanotransduction in living cells.
Abstract: In recent years, honeycomb fiber reinforced plastic
(FRP) sandwich panels have been increasingly used in various
industries. Low weight, low price and high mechanical strength are
the benefits of these structures. However, their mechanical properties
and behavior have not been fully explored. The objective of this
study is to conduct a combined numerical-statistical investigation of
honeycomb FRP sandwich beams subject to torsion load. In this
paper, the effect of geometric parameters of sandwich panel on
maximum shear strain in both face and core and angle of torsion in a
honeycomb FRP sandwich structures in torsion is investigated. The
effect of Parameters including core thickness, face skin thickness,
cell shape, cell size, and cell thickness on mechanical behavior of the
structure were numerically investigated. Main effects of factors were
considered in this paper and regression equations were derived.
Taguchi method was employed as experimental design and an
optimum parameter combination for the maximum structure stiffness
has been obtained. The results showed that cell size and face skin
thickness have the most significant impacts on torsion angle,
maximum shear strain in face and core.
Abstract: DNA Barcode provides good sources of needed
information to classify living species. The classification problem has
to be supported with reliable methods and algorithms. To analyze
species regions or entire genomes, it becomes necessary to use the
similarity sequence methods. A large set of sequences can be
simultaneously compared using Multiple Sequence Alignment which
is known to be NP-complete. However, all the used methods are still
computationally very expensive and require significant computational
infrastructure. Our goal is to build predictive models that are highly
accurate and interpretable. In fact, our method permits to avoid the
complex problem of form and structure in different classes of
organisms. The empirical data and their classification performances
are compared with other methods. Evenly, in this study, we present
our system which is consisted of three phases. The first one, is called
transformation, is composed of three sub steps; Electron-Ion
Interaction Pseudopotential (EIIP) for the codification of DNA
Barcodes, Fourier Transform and Power Spectrum Signal Processing.
Moreover, the second phase step is an approximation; it is
empowered by the use of Multi Library Wavelet Neural Networks
(MLWNN). Finally, the third one, is called the classification of DNA
Barcodes, is realized by applying the algorithm of hierarchical
classification.
Abstract: The lifetime of a wireless sensor network can be
effectively increased by using scheduling operations. Once the
sensors are randomly deployed, the task at hand is to find the largest
number of disjoint sets of sensors such that every sensor set provides
complete coverage of the target area. At any instant, only one of these
disjoint sets is switched on, while all other are switched off. This
paper proposes a heuristic search method to find the maximum
number of disjoint sets that completely cover the region. A
population of randomly initialized members is made to explore the
solution space. A set of heuristics has been applied to guide the
members to a possible solution in their neighborhood. The heuristics
escalate the convergence of the algorithm. The best solution explored
by the population is recorded and is continuously updated. The
proposed algorithm has been tested for applications which require
sensing of multiple target points, referred to as point coverage
applications. Results show that the proposed algorithm outclasses the
existing algorithms. It always finds the optimum solution, and that
too by making fewer number of fitness function evaluations than the
existing approaches.
Abstract: In this paper, we present a new segmentation approach
for liver lesions in regions of interest within MRI (Magnetic
Resonance Imaging). This approach, based on a two-cluster Fuzzy CMeans
methodology, considers the parameter variable compactness
to handle uncertainty. Fine boundaries are detected by a local
recursive merging of ambiguous pixels with a sequential forward
floating selection with Zernike moments. The method has been tested
on both synthetic and real images. When applied on synthetic images,
the proposed approach provides good performance, segmentations
obtained are accurate, their shape is consistent with the ground truth,
and the extracted information is reliable. The results obtained on MR
images confirm such observations. Our approach allows, even for
difficult cases of MR images, to extract a segmentation with good
performance in terms of accuracy and shape, which implies that the
geometry of the tumor is preserved for further clinical activities (such
as automatic extraction of pharmaco-kinetics properties, lesion
characterization, etc.).
Abstract: RF magnetron sputtering is used on the ceramic targets,
each of which contains zinc oxide (ZnO), zinc oxide doped with
aluminum (AZO) and zinc oxide doped with gallium (GZO). The XRD
analysis showed a preferred orientation along the (002) plane for ZnO,
AZO, and GZO films. The AZO film had the best electrical properties;
it had the lowest resistivity of 6.6 × 10-4 cm, the best sheet resistance of
2.2 × 10-1 Ω/square, and the highest carrier concentration of 4.3 × 1020
cm-3, as compared to the ZnO and GZO films.
Abstract: The effects of flame-holder position, the ratio of flame
holder diameter to combustion chamber diameter and injection angle
on fuel propulsive droplets sizing and effective mass fraction have
been studied by a cold flow. We named the mass of fuel vapor inside
the flammability limit as the effective mass fraction. An empty
cylinder as well as a flame-holder which are a simulator for duct
combustion has been considered. The airflow comes into the cylinder
from one side and injection operation will be done by four nozzles
which are located on the entrance of cylinder. To fulfill the
calculations a modified version of KIVA-3V code which is a
transient, three-dimensional, multiphase, multi component code for
the analysis of chemically reacting flows with sprays, is used.
Abstract: This paper is based on a large questionnaire study. The
paper presents how all participants and subgroups (upper- and
lower-level white-collar workers) answered the question, “Have you
had an ache, pain, or numbness, which you associate with desktop
computer use, in the different body parts during the last 12 months?’
14.6% of participants (19.4% of women and 8.2% of men) reported
that they had often or very often physical symptoms in the neck. Even
if our results cannot prove a causal relation of symptoms with
computer use, show that workers believe that computer use can
influence their wellbeing: this is important when devising treatment
modalities to decrease these physical symptoms.