Abstract: the work contains the results of complex investigation
related to the evaluation of condition of working blades of gas turbine
engines during fatigue tests by applying the acoustic emission
method. It demonstrates the possibility of estimating the fatigue
damage of blades in the process of factory tests. The acoustic
emission criteria for detecting and testing the kinetics of fatigue crack
distribution were detected. It also shows the high effectiveness of the
method for non-destructive testing of condition of solid and cooled
working blades for high-temperature gas turbine engines.
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: It is well known that during the developments in the
economic sector and through the financial crises occur everywhere in
the whole world, volatility measurement is the most important
concept in financial time series. Therefore in this paper we discuss
the volatility for Amman stocks market (Jordan) for certain period of
time. Since wavelet transform is one of the most famous filtering
methods and grows up very quickly in the last decade, we compare
this method with the traditional technique, Fast Fourier transform to
decide the best method for analyzing the volatility. The comparison
will be done on some of the statistical properties by using Matlab
program.
Abstract: A high-frequency low-power sinusoidal quadrature
oscillator is presented through the use of two 2nd-order low-pass
current-mirror (CM)-based filters, a 1st-order CM low-pass filter and
a CM bilinear transfer function. The technique is relatively simple
based on (i) inherent time constants of current mirrors, i.e. the
internal capacitances and the transconductance of a diode-connected
NMOS, (ii) a simple negative resistance RN formed by a resistor load
RL of a current mirror. Neither external capacitances nor inductances
are required. As a particular example, a 1.9-GHz, 0.45-mW, 2-V
CMOS low-pass-filter-based all-current-mirror sinusoidal quadrature
oscillator is demonstrated. The oscillation frequency (f0) is 1.9 GHz
and is current-tunable over a range of 370 MHz or 21.6 %. The
power consumption is at approximately 0.45 mW. The amplitude
matching and the quadrature phase matching are better than 0.05 dB
and 0.15°, respectively. Total harmonic distortions (THD) are less
than 0.3 %. At 2 MHz offset from the 1.9 GHz, the carrier to noise
ratio (CNR) is 90.01 dBc/Hz whilst the figure of merit called a
normalized carrier-to-noise ratio (CNRnorm) is 153.03 dBc/Hz. The
ratio of the oscillation frequency (f0) to the unity-gain frequency (fT)
of a transistor is 0.25. Comparisons to other approaches are also
included.
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 paper presents the modeling of nonlinear
longitudinal aerodynamics using flight data of Hansa-3 aircraft at
high angles of attack near stall. The Kirchhoff-s quasi-steady stall
model has been used to incorporate nonlinear aerodynamic effects in
the aerodynamic model used to estimate the parameters, thereby,
making the aerodynamic model nonlinear. The Maximum Likelihood
method has been applied to the flight data (at high angles of attack)
for the estimation of parameters (aerodynamic and stall
characteristics) using the nonlinear aerodynamic model. To improve
the accuracy level of the estimates, an approach of fixing the strong
parameters has also been presented.
Abstract: By employing BS (Base Station) cooperation we can
increase substantially the spectral efficiency and capacity of cellular
systems. The signals received at each BS are sent to a central unit that
performs the separation of the different MT (Mobile Terminal) using
the same physical channel. However, we need accurate sampling and
quantization of those signals so as to reduce the backhaul
communication requirements.
In this paper we consider the optimization of the quantizers for BS
cooperation systems. Four different quantizer types are analyzed and
optimized to allow better SQNR (Signal-to-Quantization Noise
Ratio) and BER (Bit Error Rate) performance.
Abstract: The position and momentum space information entropies
of hydrogen atom are exactly evaluated. Using isospectral
Hamiltonian approach, a family of isospectral potentials is constructed having same energy eigenvalues as that of the original potential. The information entropy content is obtained in position
space as well as in momentum space. It is shown that the information
entropy content in each level can be re-arranged as a function of deformation parameter.
Abstract: Intellectual capital reporting becomes critical at
universities, mainly due to the fact that knowledge is the main output
as well as input in these institutions. In addition, universities have
continuous external demands for greater information and
transparency about the use of public funds, and are increasingly
provided with greater autonomy regarding their organization,
management, and budget allocation. This situation requires new
management and reporting systems. The purpose of the present study
is to provide a model for intellectual capital report in Spanish
universities. To this end, a questionnaire was sent to every member of
the Social Councils of Spanish public universities in order to identify
which intangible elements university stakeholders demand most. Our
proposal for an intellectual capital report aims to act as a guide to
help the Spanish universities on the road to the presentation of
information on intellectual capital which can assist stakeholders to
make the right decisions.
Abstract: The hand is one of the essential parts of the body for
carrying out Activities of Daily Living (ADLs). Individuals use their
hands and fingers in everyday activities in the both the workplace
and home. Hand-intensive tasks require diverse and sometimes
extreme levels of exertion, depending on the action, movement or
manipulation involved. The authors have undertaken several studies
looking at grip choice and comfort. It is hoped that in providing
improved understanding of discomfort during ADLs this will aid in
the design of consumer products.
Previous work by the authors outlined a methodology for
calculating pain frequency and pain level for a range of tasks. From
an online survey undertaken by the authors with regards
manipulating objects during everyday tasks, tasks involving
gripping were seen to produce the highest levels of pain and
discomfort. Questioning of the participants showed that cleaning
tasks were seen to be ADL's that produced the highest levels of
discomfort, with women feeling higher levels of discomfort than
men.
This paper looks at the methodology for calculating pain
frequency and pain level with particular regards to gripping
activities. This methodology shows that activities such as mopping,
sweeping and hoovering shows the highest numbers of pain
frequency and pain level at 3112.5 frequency per month while the
pain level per person doing this action was 0.78.The study then uses
thin-film force sensors to analyze the force distribution in the hand
whilst hoovering and compares this for differing grip styles and
genders. Women were seen to have more of their hand under a
higher pressure than men when undertaking hoovering. This
suggests that women may feel greater discomfort than men since
their hand is at a higher pressure more of the time.
Abstract: The most important parameter in transformers life
expectancy is the hot-spot temperature level which accelerates the
rate of aging of the insulation. The aim of this paper is to present
thermal models for transformers loaded at prefabricated MV/LV
transformer substations and outdoor situations. The hot-spot
temperature of transformers is studied using their top-oil temperature
rise models. The thermal models proposed for hot-spot and top-oil
temperatures of different operating situations are compared. Since the
thermal transfer is different for indoor and outdoor transformers
considering their operating conditions, their hot-spot thermal models
differ from each other. The proposed thermal models are verified by
the results obtained from the experiments carried out on a typical
1600 kVA, 30 /0.4 kV, ONAN transformer for both indoor and
outdoor situations.
Abstract: This paper presents a new method of analog fault diagnosis based on back-propagation neural networks (BPNNs) using wavelet decomposition and fractal dimension as preprocessors. The proposed method has the capability to detect and identify faulty components in an analog electronic circuit with tolerance by analyzing its impulse response. Using wavelet decomposition to preprocess the impulse response drastically de-noises the inputs to the neural network. The second preprocessing by fractal dimension can extract unique features, which are the fed to a neural network as inputs for further classification. A comparison of our work with [1] and [6], which also employs back-propagation (BP) neural networks, reveals that our system requires a much smaller network and performs significantly better in fault diagnosis of analog circuits due to our proposed preprocessing techniques.
Abstract: Median filter is widely used to remove impulse noise
without blurring sharp edges. However, when noise level increased,
or with thin edges, median filter may work poorly. This paper
proposes a new filter, which will detect edges along four possible
directions, and then replace noise corrupted pixel with estimated
noise-free edge median value. Simulations show that the proposed
multi-stage directional median filter can provide excellent
performance of suppressing impulse noise in all situations.
Abstract: The Muslim faith requires individuals to fast between
the hours of sunrise and sunset during the month of Ramadan. Our
recent work has concentrated on some of the changes that take place
during the daytime when fasting. A questionnaire was developed to
assess subjective estimates of physical, mental and social activities,
and fatigue. Four days were studied: in the weeks before and after
Ramadan (control days) and during the first and last weeks of
Ramadan (experimental days). On each of these four days, this
questionnaire was given several times during the daytime and once
after the fast had been broken and just before individuals retired at
night.
During Ramadan, daytime mental, physical and social activities
all decreased below control values but then increased to abovecontrol
values in the evening. The desires to perform physical and
mental activities showed very similar patterns. That is, individuals
tried to conserve energy during the daytime in preparation for the
evenings when they ate and drank, often with friends. During
Ramadan also, individuals were more fatigued in the daytime and
napped more often than on control days. This extra fatigue probably
reflected decreased sleep, individuals often having risen earlier
(before sunrise, to prepare for fasting) and retired later (to enable
recovery from the fast).
Some physiological measures and objective measures of
performance (including the response to a bout of exercise) have also
been investigated. Urine osmolality fell during the daytime on
control days as subjects drank, but rose in Ramadan to reach values
at sunset indicative of dehydration. Exercise performance was also
compromised, particularly late in the afternoon when the fast had
lasted several hours. Self-chosen exercise work-rates fell and a set
amount of exercise felt more arduous. There were also changes in
heart rate and lactate accumulation in the blood, indicative of greater
cardiovascular and metabolic stress caused by the exercise in
subjects who had been fasting. Daytime fasting in Ramadan produces
widespread effects which probably reflect combined effects of sleep
loss and restrictions to intakes of water and food.
Abstract: Subsurface erosion in river banks and its details, in
spite of its occurrence in various parts of the world has rarely been
paid attention by researchers. In this paper, quantitative concept of
the subsurface bank erosion has been investigated for vertical banks.
Vertical banks were simulated experimentally by considering a sandy
erodible layer overlaid by clayey one under uniformly distributed
constant overhead pressure. Results of the experiments are indicated
that rate of sandy layer erosion is decreased by an increase in
overburden; likewise, substituting 20% of coarse (3.5 mm) sand layer
bed material by fine material (1.4 mm) may lead to a decrease in
erosion rate by one-third. This signifies the importance of the bed
material composition effect on sandy layers erosion due to subsurface
erosion in river banks.
Abstract: Reciprocating compressors are flexible to handle wide capacity and condition swings, offer a very efficient method of compressing almost any gas mixture in wide range of pressure, can generate high head independent of density, and have numerous applications and wide power ratings. These make them vital component in various units of industrial plants. In this paper optimum reciprocating compressor configuration regarding interstage pressures, low suction pressure, non-lubricated cylinder, speed of machine, capacity control system, compressor valve, lubrication system, piston rod coating, cylinder liner material, barring device, pressure drops, rod load, pin reversal, discharge temperature, cylinder coolant system, performance, flow, coupling, special tools, condition monitoring (including vibration, thermal and rod drop monitoring), commercial points, delivery and acoustic conditions are presented.
Abstract: Computers are being integrated in the various aspects
of human every day life in different shapes and abilities. This fact
has intensified a requirement for the software development
technologies which is ability to be: 1) portable, 2) adaptable, and 3)
simple to develop. This problem is also known as the Pervasive
Computing Problem (PCP) which can be implemented in different
ways, each has its own pros and cons and Context Oriented
Programming (COP) is one of the methods to address the PCP.
In this paper a design for a COP framework, a context aware
framework, is presented which has eliminated weak points of a
previous design based on interpreter languages, while introducing the
compiler languages power in implementing these frameworks.
The key point of this improvement is combining COP and
Dependency Injection (DI) techniques. Both old and new frameworks
are analyzed to show advantages and disadvantages. Finally a
simulation of both designs is proposed to indicating that the practical
results agree with the theoretical analysis while the new design runs
almost 8 times faster.
Abstract: The purpose of this study was to explore the learning
effects on dance domain in Arts Curriculum at junior and senior high
levels. A total of 1,366 students from 9th to 11th grade of different
areas from Taiwan were administered a self-designed dance
achievement test. Data were analyzed through descriptive analysis,
independent sample t test, one-way ANOVA and Post hoc comparison
analysis using Scheffé Test. The results showed (1) female students
Abstract: Information on weed distribution within the field is necessary to implement spatially variable herbicide application. Since hand labor is costly, an automated weed control system could be feasible. This paper deals with the development of an algorithm for real time specific weed recognition system based on Histogram Maxima with threshold of an image that is used for the weed classification. This algorithm is specifically developed to classify images into broad and narrow class for real-time selective herbicide application. The developed system has been tested on weeds in the lab, which have shown that the system to be very effectiveness in weed identification. Further the results show a very reliable performance on images of weeds taken under varying field conditions. The analysis of the results shows over 95 percent classification accuracy over 140 sample images (broad and narrow) with 70 samples from each category of weeds.
Abstract: Since the world printing industry has to confront
globalization with a constant change, the Thai printing industry, as a
small but increasingly significant part of the world printing industry,
cannot inevitably escape but has to encounter with the similar change
and also the need to revamp its production processes, designs and
technology to make them more appealing to both international and
domestic market. The essential question is what is the Thai
competitive edge in the printing industry in changing environment?
This research is aimed to study the Thai level of competitive edge in
terms of marketing, technology, environment friendly, and the level
of satisfaction of the process of using printing machines. To access
the extent to which is the trends in competitiveness of Thai printing
industry, both quantitative and qualitative study were conducted. The
quantitative analysis was restricted to 100 respondents. The
qualitative analysis was restricted to a focus group of 10 individuals
from various backgrounds in the Thai printing industry. The findings
from the quantitative analysis revealed that the overall mean scores
are 4.53, 4.10, and 3.50 for the competitiveness of marketing, the
competitiveness of technology, and the competitiveness of being
environment friendly respectively. However, the level of satisfaction
for the process of using machines has a mean score only 3.20. The
findings from the qualitative analysis have revealed that target
customers have increasingly reordered due to their contentment in
both low prices and the acceptable quality of the products. Moreover,
the Thai printing industry has a tendency to convert to ambient green
technology which is friendly to the environment. The Thai printing
industry is choosing to produce or substitute with products that are
less damaging to the environment. It is also found that the Thai
printing industry has been transformed into a very competitive
industry which bargaining power rests on consumers who have a
variety of choices.