Abstract: The performance and the plasma created by a pulsed
magnetoplasmadynamic thruster for small satellite application is
studied to understand better the ablation and plasma propagation
processes occurring during the short-time discharge. The results can
be applied to improve the quality of the thruster in terms of efficiency,
and to tune the propulsion system to the needs required by the satellite
mission. Therefore, plasma measurements with a high-speed camera
and induction probes, and performance measurements of mass bit
and impulse bit were conducted. Values for current sheet propagation
speed, mean exhaust velocity and thrust efficiency were derived from
these experimental data. A maximum in current sheet propagation
was found by the high-speed camera measurements for a medium
energy input and confirmed by the induction probes. A quasilinear
tendency between the mass bit and the energy input, the current
action integral respectively, was found, as well as a linear tendency
between the created impulse and the discharge energy. The highest
mean exhaust velocity and thrust efficiency was found for the highest
energy input.
Abstract: The objective of this paper is to construct a creativity
composite index designed to capture the growing role of creativity in
driving economic and social development for the 27 European Union
countries.
The paper proposes a new approach for the measurement of EU-27
creative potential and for determining its capacity to attract and
develop creative human capital. We apply a modified version of the
3T model developed by Richard Florida and Irene Tinagli for
constructing a Euro-Creativity Index. The resulting indexes establish
a quantitative base for policy makers, supporting their efforts to
determine the contribution of creativity to economic development.
Abstract: Selection of the best possible set of suppliers has a
significant impact on the overall profitability and success of any
business. For this reason, it is usually necessary to optimize all
business processes and to make use of cost-effective alternatives for
additional savings. This paper proposes a new efficient context-aware
supplier selection model that takes into account possible changes of
the environment while significantly reducing selection costs. The
proposed model is based on data clustering techniques while
inspiring certain principles of online algorithms for an optimally
selection of suppliers. Unlike common selection models which re-run
the selection algorithm from the scratch-line for any decision-making
sub-period on the whole environment, our model considers the
changes only and superimposes it to the previously defined best set
of suppliers to obtain a new best set of suppliers. Therefore, any recomputation
of unchanged elements of the environment is avoided
and selection costs are consequently reduced significantly. A
numerical evaluation confirms applicability of this model and proves
that it is a more optimal solution compared with common static
selection models in this field.
Abstract: Inverse kinematics analysis plays an important role in developing a robot manipulator. But it is not too easy to derive the inverse kinematic equation of a robot manipulator especially robot manipulator which has numerous degree of freedom. This paper describes an application of Artificial Neural Network for modeling the inverse kinematics equation of a robot manipulator. In this case, the robot has three degree of freedoms and the robot was implemented for drilling a printed circuit board. The artificial neural network architecture used for modeling is a multilayer perceptron networks with steepest descent backpropagation training algorithm. The designed artificial neural network has 2 inputs, 2 outputs and varies in number of hidden layer. Experiments were done in variation of number of hidden layer and learning rate. Experimental results show that the best architecture of artificial neural network used for modeling inverse kinematics of is multilayer perceptron with 1 hidden layer and 38 neurons per hidden layer. This network resulted a RMSE value of 0.01474.
Abstract: Cancers could normally be marked by a number of
differentially expressed genes which show enormous potential as
biomarkers for a certain disease. Recent years, cancer classification
based on the investigation of gene expression profiles derived by
high-throughput microarrays has widely been used. The selection of
discriminative genes is, therefore, an essential preprocess step in
carcinogenesis studies. In this paper, we have proposed a novel gene
selector using information-theoretic measures for biological
discovery. This multivariate filter is a four-stage framework through
the analyses of feature relevance, feature interdependence, feature
redundancy-dependence and subset rankings, and having been
examined on the colon cancer data set. Our experimental result show
that the proposed method outperformed other information theorem
based filters in all aspect of classification errors and classification
performance.
Abstract: The paper presents the optimization problem for the
multi-element synthetic transmit aperture method (MSTA) in
ultrasound imaging applications. The optimal choice of the transmit
aperture size is performed as a trade-off between the lateral
resolution, penetration depth and the frame rate. Results of the
analysis obtained by a developed optimization algorithm are
presented. Maximum penetration depth and the best lateral resolution
at given depths are chosen as the optimization criteria. The
optimization algorithm was tested using synthetic aperture data of
point reflectors simulated by Filed II program for Matlab® for the
case of 5MHz 128-element linear transducer array with 0.48 mm
pitch are presented. The visualization of experimentally obtained
synthetic aperture data of a tissue mimicking phantom and in vitro
measurements of the beef liver are also shown. The data were
obtained using the SonixTOUCH Research systemequipped with a
linear 4MHz 128 element transducerwith 0.3 mm element pitch, 0.28
mm element width and 70% fractional bandwidth was excited by one
sine cycle pulse burst of transducer's center frequency.
Abstract: This paper begins with formal defining of human rights and freedoms, and the basic document regarding the said subject is undoubtedly French Declaration of the Rights of Man and of the Citizen from 789. This paper furthermore parses legal sources relevant for the workers' rights in legal system of the Republic of Croatia, international contracts and the Labour Act, which is also a master bill regarding workers' rights The authors are also dealing with issues of Constitutional Court of the Republic of Croatia and its' position in judicial system of the Republic of Croatia, as well as with the specifics of Constitutional Complaint, and the crucial part of the paper is based on the research conducted with an aim to determine implementation of rights and liberties guaranteed by the articles 54. and 55. of the Constitution of the Republic of Croatia by means of Constitutional Complaint.
Abstract: The purpose of this study was to evaluate and
compare new indices based on the discrete wavelet transform
with another spectral parameters proposed in the literature as
mean average voltage, median frequency and ratios between
spectral moments applied to estimate acute exercise-induced
changes in power output, i.e., to assess peripheral muscle
fatigue during a dynamic fatiguing protocol. 15 trained
subjects performed 5 sets consisting of 10 leg press, with 2
minutes rest between sets. Surface electromyography was
recorded from vastus medialis (VM) muscle. Several surface
electromyographic parameters were compared to detect
peripheral muscle fatigue. These were: mean average voltage
(MAV), median spectral frequency (Fmed), Dimitrov spectral
index of muscle fatigue (FInsm5), as well as other five
parameters obtained from the discrete wavelet transform
(DWT) as ratios between different scales. The new wavelet
indices achieved the best results in Pearson correlation
coefficients with power output changes during acute dynamic
contractions. Their regressions were significantly different
from MAV and Fmed. On the other hand, they showed the
highest robustness in presence of additive white gaussian
noise for different signal to noise ratios (SNRs). Therefore,
peripheral impairments assessed by sEMG wavelet indices
may be a relevant factor involved in the loss of power output
after dynamic high-loading fatiguing task.
Abstract: The mosaicing technique has been employed in more and more application fields, from entertainment to scientific ones. In the latter case, often the final evaluation is still left to human beings, that assess visually the quality of the mosaic. Many times, a lack of objective measurements in microscopic mosaicing may prevent the mosaic from being used as a starting image for further analysis. In this work we analyze three different metrics and indexes, in the domain of signal analysis, image analysis and visual quality, to measure the quality of different aspects of the mosaicing procedure, such as registration errors and visual quality. As the case study we consider the mosaicing algorithm we developed. The experiments have been carried out by considering mosaics with very different features: histological samples, that are made of detailed and contrasted images, and live stem cells, that show a very low contrast and low detail levels.
Abstract: The production of a plant can be measured in terms of
seeds. The generation of seeds plays a critical role in our social and
daily life. The fruit production which generates seeds, depends on the
various parameters of the plant, such as shoot length, leaf number,
root length, root number, etc When the plant is growing, some leaves
may be lost and some new leaves may appear. It is very difficult to
use the number of leaves of the tree to calculate the growth of the
plant.. It is also cumbersome to measure the number of roots and
length of growth of root in several time instances continuously after
certain initial period of time, because roots grow deeper and deeper
under ground in course of time. On the contrary, the shoot length of
the tree grows in course of time which can be measured in different
time instances. So the growth of the plant can be measured using the
data of shoot length which are measured at different time instances
after plantation. The environmental parameters like temperature, rain
fall, humidity and pollution are also play some role in production of
yield. The soil, crop and distance management are taken care to
produce maximum amount of yields of plant. The data of the growth
of shoot length of some mustard plant at the initial stage (7,14,21 &
28 days after plantation) is available from the statistical survey by a
group of scientists under the supervision of Prof. Dilip De. In this
paper, initial shoot length of Ken( one type of mustard plant) has
been used as an initial data. The statistical models, the methods of
fuzzy logic and neural network have been tested on this mustard
plant and based on error analysis (calculation of average error) that
model with minimum error has been selected and can be used for the
assessment of shoot length at maturity. Finally, all these methods
have been tested with other type of mustard plants and the particular
soft computing model with the minimum error of all types has been
selected for calculating the predicted data of growth of shoot length.
The shoot length at the stage of maturity of all types of mustard
plants has been calculated using the statistical method on the
predicted data of shoot length.
Abstract: Design for Disassembly (DfD) aims to reuse the
structural components instead of demolition followed by recycling of
the demolition debris. This concept preserves the invested embodied
energy of materials, thus reducing inputs of new embodied energy
during materials reprocessing or remanufacturing. Both analytical and
experimental research on a proposed DfD beam-column connection
for use in residential apartments is currently investigated at the
National University of Singapore in collaboration with the Housing
and Development Board of Singapore. The present study reports on
the results of a numerical analysis of the proposed connection utilizing
finite element analysis. The numerical model was calibrated and
validated by comparison against experimental results. Results of a
parametric study will also be presented and discussed.
Abstract: It is well known that Logistic Regression is the gold
standard method for predicting clinical outcome, especially
predicting risk of mortality. In this paper, the Decision Tree method
has been proposed to solve specific problems that commonly use
Logistic Regression as a solution. The Biochemistry and
Haematology Outcome Model (BHOM) dataset obtained from
Portsmouth NHS Hospital from 1 January to 31 December 2001 was
divided into four subsets. One subset of training data was used to
generate a model, and the model obtained was then applied to three
testing datasets. The performance of each model from both methods
was then compared using calibration (the χ2 test or chi-test) and
discrimination (area under ROC curve or c-index). The experiment
presented that both methods have reasonable results in the case of the
c-index. However, in some cases the calibration value (χ2) obtained
quite a high result. After conducting experiments and investigating
the advantages and disadvantages of each method, we can conclude
that Decision Trees can be seen as a worthy alternative to Logistic
Regression in the area of Data Mining.
Abstract: Over 90% of the world trade is carried by the
international shipping industry. As most of the countries are
developing, seaborne trade continues to expand to bring benefits for
consumers across the world. Studies show that world trade will
increase 70-80% through shipping in the next 15-20 years. Present
global fleet of 70000 commercial ships consumes approximately 200
million tonnes of diesel fuel a year and it is expected that it will be
around 350 million tonnes a year by 2020. It will increase the
demand for fuel and also increase the concentration of CO2 in the
atmosphere. So, it-s essential to control this massive fuel
consumption and CO2 emission. The idea is to utilize a diesel-wind
hybrid system for ship propulsion. Use of wind energy by installing
modern wing-sails in ships can drastically reduce the consumption of
diesel fuel. A huge amount of wind energy is available in oceans.
Whenever wind is available the wing-sails would be deployed and
the diesel engine would be throttled down and still the same forward
speed would be maintained. Wind direction in a particular shipping
route is not same throughout; it changes depending upon the global
wind pattern which depends on the latitude. So, the wing-sail
orientation should be such that it optimizes the use of wind energy.
We have made a computer programme in which by feeding the data
regarding wind velocity, wind direction, ship-motion direction; we
can find out the best wing-sail position and fuel saving for
commercial ships. We have calculated net fuel saving in certain
international shipping routes, for instance, from Mumbai in India to
Durban in South Africa. Our estimates show that about 8.3% diesel
fuel can be saved by utilizing the wind. We are also developing an
experimental model of the ship employing airfoils (small scale wingsail)
and going to test it in National Wind Tunnel Facility in IIT
Kanpur in order to develop a control mechanism for a system of
airfoils.
Abstract: An attractor neural network on the small-world topology
is studied. A learning pattern is presented to the network, then
a stimulus carrying local information is applied to the neurons and
the retrieval of block-like structure is investigated. A synaptic noise
decreases the memory capability. The change of stability from local
to global attractors is shown to depend on the long-range character
of the network connectivity.
Abstract: Fracture process in mechanically loaded steel fiber
reinforced high-strength (SFRHSC) concrete is characterized by
fibers bridging the crack providing resistance to its opening.
Structural SFRHSC fracture model was created; material fracture
process was modeled, based on single fiber pull-out laws, which were
determined experimentally (for straight fibers, fibers with end hooks
(Dramix), and corrugated fibers (Tabix)) as well as obtained
numerically ( using FEM simulations). For this purpose experimental
program was realized and pull-out force versus pull-out fiber length
was obtained (for fibers embedded into concrete at different depth
and under different angle). Model predictions were validated by
15x15x60cm prisms 4 point bending tests. Fracture surfaces analysis
was realized for broken prisms with the goal to improve elaborated
model assumptions. Optimal SFRHSC structures were recognized.
Abstract: Electrocardiogram (ECG) is considered to be the
backbone of cardiology. ECG is composed of P, QRS & T waves and
information related to cardiac diseases can be extracted from the
intervals and amplitudes of these waves. The first step in extracting
ECG features starts from the accurate detection of R peaks in the
QRS complex. We have developed a robust R wave detector using
wavelets. The wavelets used for detection are Daubechies and
Symmetric. The method does not require any preprocessing therefore,
only needs the ECG correct recordings while implementing the
detection. The database has been collected from MIT-BIH arrhythmia
database and the signals from Lead-II have been analyzed. MatLab
7.0 has been used to develop the algorithm. The ECG signal under
test has been decomposed to the required level using the selected
wavelet and the selection of detail coefficient d4 has been done based
on energy, frequency and cross-correlation analysis of decomposition
structure of ECG signal. The robustness of the method is apparent
from the obtained results.
Abstract: This study presents the performance of membrane
bioreactor in treating high phosphate wastewater. The laboratory
scale MBR was operated at permeate flux of 25 L/m2.h with a hollow
fiber membrane (polypropylene, approx. pore size 0.01 - 0.2 μm) at
hydraulic retention time (HRT) of 12 hrs. Scanning electron
microscopy (SEM) and energy diffusive X-ray (EDX) analyzer were
used to characterize the membrane foulants. Results showed that the
removal efficiencies of COD, TSS, NH3-N and PO4
3- were 93, 98, 80
and 30% respectively. On average 91% of influent soluble microbial
products (SMP) were eliminated, with the eliminations of
polysaccharides mostly above 80%. The main fouling resistance was
cake resistance. It should be noted that SMP were found in major
portions of mixed liquor that played a relatively significant role in
membrane fouling. SEM and EDX analyses indicated that the
foulants covering the membrane surfaces comprises not only organic
substances but also inorganic elements including Mg, Ca, Al, K and
P.
Abstract: The financial crisis has decreased the opportunities of
small businesses to acquire financing through conventional financial
actors, such as commercial banks. This credit constraint is partly the
reason for the emergence of new alternatives of financing, in addition
to the spreading opportunities for communication and secure
financial transfer through Internet. One of the most interesting venues
for finance is termed “crowdfunding". As the term suggests
crowdfunding is an appeal to prospective customers and investors to
form a crowd that will finance projects that otherwise would find it
hard to generate support through the most common financial actors.
Crowdfunding is in this paper divided into different models; the
threshold model, the microfinance model, the micro loan model and
the equity model. All these models add to the financial possibilities of
emerging entrepreneurs.
Abstract: The oil and gas industry has moved towards Load and
Resistance Factor Design through API RP2A - LRFD and the
recently published international standard, ISO-19902, for design of
fixed steel offshore structures. The ISO 19902 is intended to provide
a harmonized design practice that offers a balanced structural fitness
for the purpose, economy and safety. As part of an ongoing work, the
reliability analysis of tubular joints of the jacket structure has been
carried out to calibrate the load and resistance factors for the design
of offshore platforms in Malaysia, as proposed in the ISO.
Probabilistic models have been established for the load effects (wave,
wind and current) and the tubular joints strengths. In this study the
First Order Reliability Method (FORM), coded in MATLAB
Software has been employed to evaluate the reliability index of the
typical joints, designed using API RP2A - WSD and ISO 19902.
Abstract: Bone remodeling occurs by the balanced action of
bone resorbing osteoclasts (OC) and bone-building osteoblasts.
Increased bone resorption by excessive OC activity contributes
to malignant and non-malignant diseases including osteoporosis.
To study OC differentiation and function, OC formed in
in vitro cultures are currently counted manually, a tedious
procedure which is prone to inter-observer differences. Aiming
for an automated OC-quantification system, classification of
OC and precursor cells was done on fluorescence microscope
images based on the distinct appearance of fluorescent nuclei.
Following ellipse fitting to nuclei, a combination of eight
features enabled clustering of OC and precursor cell nuclei.
After evaluating different machine-learning techniques, LOGREG
achieved 74% correctly classified OC and precursor cell
nuclei, outperforming human experts (best expert: 55%). In
combination with the automated detection of total cell areas,
this system allows to measure various cell parameters and most
importantly to quantify proteins involved in osteoclastogenesis.