Abstract: This work is focused on the numerical prediction of the fracture resistance of a flat stiffened panel made of the aluminium alloy 2024 T3 under a monotonic traction condition. The performed numerical simulations have been based on the micromechanical Gurson-Tvergaard (GT) model for ductile damage. The applicability of the GT model to this kind of structural problems has been studied and assessed by comparing numerical results, obtained by using the WARP 3D finite element code, with experimental data available in literature. In the sequel a home-made procedure is presented, which aims to increase the residual strength of a cracked stiffened aluminum panel and which is based on the stochastic design improvement (SDI) technique; a whole application example is then given to illustrate the said technique.
Abstract: In this paper, we consider the problem of tracking
multiple maneuvering targets using switching multiple target motion
models. With this paper, we aim to contribute in solving the problem
of model-based body motion estimation by using data coming from
visual sensors. The Interacting Multiple Model (IMM) algorithm is
specially designed to track accurately targets whose state and/or
measurement (assumed to be linear) models changes during motion
transition. However, when these models are nonlinear, the IMM
algorithm must be modified in order to guarantee an accurate track.
In this paper we propose to avoid the Extended Kalman filter because
of its limitations and substitute it with the Unscented Kalman filter
which seems to be more efficient especially according to the
simulation results obtained with the nonlinear IMM algorithm (IMMUKF).
To resolve the problem of data association, the JPDA
approach is combined with the IMM-UKF algorithm, the derived
algorithm is noted JPDA-IMM-UKF.
Abstract: In this paper, we have applied the homotopy perturbation
method (HPM) for obtaining the analytical solution of unsteady
flow of gas through a porous medium and we have also compared the
findings of this research with some other analytical results. Results
showed a very good agreement between results of HPM and the
numerical solutions of the problem rather than other analytical solutions
which have previously been applied. The results of homotopy
perturbation method are of high accuracy and the method is very
effective and succinct.
Abstract: Recently, the health of retired National Football
League players, particularly lineman has been investigated. A number of studies have reported increased cardiometabolic risk, premature ardiovascular disease and incidence of type 2 diabetes. Rugby union players have somatotypes very similar
to National Football league players which suggest that rugby players may have similar health risks. The International Golden Oldies World Rugby Festival (GORF) provided a
unique opportunity to investigate the demographics of veteran rugby players. METHODOLOGIES: A cross-sectional, observational study was completed using an online web-based
questionnaire that consisted of medical history and
physiological measures. Data analysis was completed using a one sample t-test (50yrs) and Chi-square test. RESULTS: A total of 216 veteran rugby competitors
(response rate = 6.8%) representing 10 countries, aged 35-72 yrs (mean 51.2, S.D. ±8.0), participated in the online survey. As a group, the incidence of current smokers was low at 8.8%
(avg 72.4 cigs/wk) whilst the percentage consuming alcohol
was high (93.1% (avg 11.2 drinks/wk). Competitors reported
the following top six chronic diseases/disorders; hypertension
(18.6%), arthritis (OA/RA, 11.5%), asthma (9.3%),
hyperlipidemia (8.2%), diabetes (all types, 7.5%) and gout (6%), there were significant differences between groups with
regard to cancer (all types) and migraines. When compared to
the Australian general population (Australian Bureau of Statistics data, n=18,000), GORF competitors had a
Climstein Mike, Walsh Joe (corresponding author) and Burke Stephen
School of Exercise Science, Australian Catholic University, 25A Barker Road,
Strathfield, Sydney, NSW, 2016, Australia (e-mail:
[email protected], [email protected],
[email protected]).
John Best is with Orthosports, 160 Belmore Rd., Randwick, Sydney,NSW
2031, Australia (e-mail: [email protected]).
Heazlewood, Ian Timothy is with School of Environmental and Life
Sciences, Faculty Education, Health and Science, Charles Darwin University,
Precinct Yellow Building 2, Charles Darwin University, NT 0909, Australia
(e-mail: [email protected]).
Kettunen Jyrki Arcada University of Applied Sciences, Jan-Magnus
Janssonin aukio 1, FI-00550, Helsinki, Finland (e-mail:
[email protected]).
Adams Kent is with California State University Monterey Bay, Kinesiology Department, 100 Campus Center, Seaside, CA., 93955, USA (email: [email protected]).
DeBeliso Mark is with Department of Physical Education and Human
Performance, Southern Utah University, 351 West University Blvd, Cedar
City, Utah, USA (e-mail: [email protected]).
significantly lower incidence of anxiety (p
Abstract: This paper describes a platform that faces the main
research areas for e-learning educational contents. Reusability tackles
the possibility to use contents in different courses reducing costs and
exploiting available data from repositories. In our approach the
production of educational material is based on templates to reuse
learning objects. In terms of interoperability the main challenge lays
on reaching the audience through different platforms. E-learning
solution must track social consumption evolution where nowadays
lots of multimedia contents are accessed through the social networks.
Our work faces it by implementing a platform for generation of
multimedia presentations focused on the new paradigm related to
social media. The system produces videos-courses on top of web
standard SMIL (Synchronized Multimedia Integration Language)
ready to be published and shared. Regarding interfaces it is
mandatory to satisfy user needs and ease communication. To
overcome it the platform deploys virtual teachers that provide natural
interfaces while multimodal features remove barriers to pupils with
disabilities.
Abstract: This paper presents the application of Intelligent
Techniques to the various duties of Intelligent Condition Monitoring
Systems (ICMS) for Unmanned Aerial Vehicle (UAV) Robots. These
Systems are intended to support these Intelligent Robots in the event
of a Fault occurrence. Neural Networks are used for Diagnosis, whilst
Fuzzy Logic is intended for Prognosis and Remedy. The ultimate
goals of ICMS are to save large losses in financial cost, time and
data.
Abstract: Clustering algorithms are attractive for the task of class identification in spatial databases. However, the application to large spatial databases rises the following requirements for clustering algorithms: minimal requirements of domain knowledge to determine the input parameters, discovery of clusters with arbitrary shape and good efficiency on large databases. The well-known clustering algorithms offer no solution to the combination of these requirements. In this paper, a density based clustering algorithm (DCBRD) is presented, relying on a knowledge acquired from the data by dividing the data space into overlapped regions. The proposed algorithm discovers arbitrary shaped clusters, requires no input parameters and uses the same definitions of DBSCAN algorithm. We performed an experimental evaluation of the effectiveness and efficiency of it, and compared this results with that of DBSCAN. The results of our experiments demonstrate that the proposed algorithm is significantly efficient in discovering clusters of arbitrary shape and size.
Abstract: Theobjective of this study was to evaluate the optimal
treatment condition of Fenton oxidation process to removal
contaminant in soil slurry contaminated by petroleum hydrocarbons.
This research studied somefactors that affect the removal efficiency
of petroleum hydrocarbons in soil slurry including molar ratio of
hydrogen peroxide (H2O2) to ferrous ion(Fe2+), pH condition and
reaction time.The resultsdemonstrated that the optimum condition
was that the molar ratio of H2O2:Fe3+ was 200:1,the pHwas 4.0and
the rate of reaction was increasing rapidly from starting point to 7th
hour and destruction kinetic rate (k) was 0.24 h-1. Approximately
96% of petroleum hydrocarbon was observed(initialtotal petroleum
hydrocarbon (TPH) concentration = 70±7gkg-1)
Abstract: At present, the tendency to implement the conditionbased
maintenance (CBM), which allows the optimization of the
expenses for equipment monitoring, is more and more evident; also,
the transformer substations with remote monitoring are increasingly
used. This paper reviews all the advantages of the on-line monitoring
and presents an equipment for on-line monitoring of bushings, which
is the own contribution of specialists who are the authors of this
paper. The paper presents a study of the temperature field, using the
finite element method. For carrying out this study, the 3D modelling
of the above mentioned bushing was performed. The analysis study is
done taking into account the extreme thermal stresses, focusing at the
level of the first cooling wing section of the ceramic insulator. This
fact enables to justify the tanδ variation in time, depending on the
transformer loading and the environmental conditions. With a view
to reducing the variation of dielectric losses in bushing insulation, the
use of ferrofuids instead of mineral oils is proposed.
Abstract: Ovshinsky initiated scientific research in the field of
amorphous and disordered materials that continues to this day. The
Ovshinsky Effect where the resistance of thin GST films is
significantly reduced upon the application of low voltage is of
fundamental importance in phase-change - random access memory
(PC-RAM) devices.GST stands for GdSbTe chalcogenide type
glasses.However, the Ovshinsky Effect is not without controversy.
Ovshinsky thought the resistance of GST films is reduced by the
redistribution of charge carriers; whereas, others at that time including
many PC-RAM researchers today argue that the GST resistance
changes because the GST amorphous state is transformed to the
crystalline state by melting, the heat supplied by external heaters. In
this controversy, quantum mechanics (QM) asserts the heat capacity of
GST films vanishes, and therefore melting cannot occur as the heat
supplied cannot be conserved by an increase in GST film
temperature.By precluding melting, QM re-opens the controversy
between the melting and charge carrier mechanisms. Supporting
analysis is presented to show that instead of increasing GST film
temperature, conservation proceeds by the QED induced creation of
photons within the GST film, the QED photons confined by TIR. QED
stands for quantum electrodynamics and TIR for total internal
reflection. The TIR confinement of QED photons is enhanced by the
fact the absorbedheat energy absorbed in the GST film is concentrated
in the TIR mode because of their high surface to volume ratio. The
QED photons having Planck energy beyond the ultraviolet produce
excitons by the photoelectric effect, the electrons and holes of which
reduce the GST film resistance.
Abstract: Unsteady magnetohydrodynamics (MHD) boundary
layer flow and heat transfer over a continuously stretching surface in
the presence of radiation is examined. By similarity transformation,
the governing partial differential equations are transformed to a set of
ordinary differential equations. Numerical solutions are obtained by
employing the Runge-Kutta-Fehlberg method scheme with shooting
technique in Maple software environment. The effects of
unsteadiness parameter, radiation parameter, magnetic parameter and
Prandtl number on the heat transfer characteristics are obtained and
discussed. It is found that the heat transfer rate at the surface
increases as the Prandtl number and unsteadiness parameter increase
but decreases with magnetic and radiation parameter.
Abstract: We present a genetic algorithm application to the problem of object registration (i.e., object detection, localization and recognition) in a class of medical images containing various types of blood cells. The genetic algorithm approach taken here is seen to be most appropriate for this type of image, due to the characteristics of the objects. Successful cell registration results on real life microscope images of blood cells show the potential of the proposed approach.
Abstract: The extract of milk thistle contains a mix of flavonolignans termed silymarine.. In order to analysis influence of growth regulators, genotype, explant and subculture on the accumulation of flavonolignans, a study was carried out by using two genotype (Budakalszi and Noor abad moghan cultivars), cotyledon and hypocotyle explants, solid media of MS supplemented by different combinations of two growth regulators; Kinetin (0.1, 1 mg/l) and 2,4-D (1, 2 mg/l). Seeds of the plant were germinated in MS media whitout growth regulators in growth chamber at 26°C and darkness condition. In order to callus induction, the culture media was supplemented whit different concentrations of 2,4-D and kinetin. Calli obtained from explants were sub-cultured four times into the fresh media of the first experiment. flavonoides was extracted from calli in four subcultures. The flavonoid components were determined by high- performance liquid choromatography (HPLC) and separated into Taxifolin, Silydianin+Silychristin, Silybin A+B and Isosilybin A+B. Results showed that with increasing callus age, increased accumulation of silybin A+B, but reduced Isosilybin A+B content. Highest accumulation of Taxifolin was observed at first calli. Calli produced from cotyledon explant of Budakalszi cultivar were superior for Silybin A+B, where calli from hypocotyl explant produced higher amount of Taxifolin and Silydianin+Silychristin. The best cultivar for Silymarin production in this study was Budakalszi cultivar. High amount of SBN A+B and TXF were obtained from hypocotil explant.
Abstract: Nurses in an Armed Force Hospital (AFH) expose to stronger stress than those in a civil hospital, especially in an emergency department (ED). Ironically, stresses of these nurses received few if any attention in academic research in the past. This study collects 227 samples from the emergency departments of four armed force hospitals in central and southern Taiwan. The research indicates that the top five stressors are a massive casualty event, delayed physician support, overloads of routine work, overloads of assignments, and annoying paper work. Excessive work loading was found to be the primary source of stress. Nurses who were perceived to have greater stress levels were more inclined to deploy emotion-oriented approaches and more likely to seek job rotations. Professional stressors and problem-oriented approaches were positively correlated. Unlike other local studies, this study concludes that the excessive work-loading is more stressful in an AFH.
Abstract: Extracellular ubiquitin in vivo effect on regenerative liver cells and liver histoarchitectonics has been studied. Experiments were performed on mature female white rats. Partial hepatectomy was made using the modified method of Higgins and Anderson. Standard histopathological assessment of liver tissue was used. Proliferative activity of hepatocytes was analyzed by colchicine mitotic index and immunohistochemical staining on ki67. We have found that regardless of number of injections and dose of extracellular ubiquitin liver histology has not been changed, so at tissue level no effect was observed. In vivo double injection of ubiquitin significantly decreases the mitotic activity at 32 hour point after partial hepatectomy. Thus, we can conclude that in vivo injected extracellular ubiquitin inhibits proliferative activity of hepatocytes in partially hepatectomyzed rats.
Abstract: This study deals with the phenomena of reflection and transmission (refraction) of qSV-waves, for an incident of quasi transverse vertically waves, at a plane interface of two semi-infinite piezoelectric elastic media under the influence of the initial stresses. The relations governing the reflection and transmission coefficients of these reflected waves for various suitable boundary conditions are derived. We have shown analytically that reflection and transmission coefficients of (qP) and (qSV) waves depend upon the angle of incidence, the parameters of electric potential, the material constants of the medium as will as the initial stresses presented in the media. The numerical calculations of the reflection and transmission amplitude ratios for different values of initial stresses have been carried out by computer for different materials as examples and the results are given in the form of graphs. Finally, some of particular cases are considered.
Abstract: Effect of high temperature exposure on properties of cement mortar containing municipal solid waste incineration (MSWI) bottom ash as partial natural aggregate replacement is analyzed in the paper. The measurements of mechanical properties, bulk density, matrix density, total open porosity, sorption and desorption isotherms are done on samples exposed to the temperatures of 20°C to 1000°C. TGA analysis is performed as well. Finally, the studied samples are analyzed by IR spectroscopy in order to evaluate TGA data.
Abstract: In this paper we propose an enhanced equalization technique for multi-carrier code division multiple access (MC-CDMA). This method is based on the control of Equal Gain Combining (EGC) technique. Indeed, we introduce a new level changer to the EGC equalizer in order to adapt the equalization parameters to the channel coefficients. The optimal equalization level is, first, determined by channel training. The new approach reduces drastically the mutliuser interferences caused by interferes, without increasing the noise power. To compare the performances of the proposed equalizer, the theoretical analysis and numerical performances are given.
Abstract: Utilizing echoic intension and distribution from different organs and local details of human body, ultrasonic image can catch important medical pathological changes, which unfortunately may be affected by ultrasonic speckle noise. A feature preserving ultrasonic image denoising and edge enhancement scheme is put forth, which includes two terms: anisotropic diffusion and edge enhancement, controlled by the optimum smoothing time. In this scheme, the anisotropic diffusion is governed by the local coordinate transformation and the first and the second order normal derivatives of the image, while the edge enhancement is done by the hyperbolic tangent function. Experiments on real ultrasonic images indicate effective preservation of edges, local details and ultrasonic echoic bright strips on denoising by our scheme.
Abstract: For maintenance of a spine stability during the
postoperative period a transpedicular fixing of its elements is often
used. Usually the transpedicular systems are formed of rods which as
a result form a design of the frame type, fastening by screws to
vertebras. Such design should be rigid and perceive loadings
operating from the spine without essential deformations. From the
perfection point of view of known designs their stress
whole, and each of elements, in particular is of interest. In this study
the modeling of the transpedicular screw is performed and
estimation of its deformations taking into account interaction with a
vertebra body having variable structure is made.