Abstract: A numerical simulation of micro Poiseuille flow has
performed for rarefied and compressible flow at slip flow regimes.
The wall roughness is simulated in two cases with triangular
microelements and random micro peaks distributed on wall surfaces
to study the effects of roughness shape and distribution on flow field.
Two values of Mach and Knudsen numbers have used to investigate
the effects of rarefaction as well as compressibility. The numerical
results have also checked with available theoretical and experimental
relations and good agreements has achieved. High influence of
roughness shape can be seen for both compressible and
incompressible rarefied flows. In addition it is found that rarefaction
has more significant effect on flow field in microchannels with
higher relative roughness. It is also found that compressibility has
more significant effects on Poiseuille number when relative
roughness increases.
Abstract: A model of vortex wake is suggested to determine the
induced power during animal hovering flight. The wake is modeled
by a series of equi-spaced rigid rectangular vortex plates, positioned
horizontally and moving vertically downwards with identical speeds;
each plate is generated during powering of the functionally wing
stroke. The vortex representation of the wake considered in the
current theory allows a considerable loss of momentum to occur. The
current approach accords well with the nature of the wingbeat since it
considers the unsteadiness in the wake as an important fluid
dynamical characteristic. Induced power in hovering is calculated as
the aerodynamic power required to generate the vortex wake system.
Specific mean induced power to mean wing tip velocity ratio is
determined by solely the normal spacing parameter (f) for a given
wing stroke amplitude. The current theory gives much higher specific
induced power estimate than anticipated by classical methods.
Abstract: The complex hybrid and nonlinear nature of many processes that are met in practice causes problems with both structure modelling and parameter identification; therefore, obtaining a model that is suitable for MPC is often a difficult task. The basic idea of this paper is to present an identification method for a piecewise affine (PWA) model based on a fuzzy clustering algorithm. First we introduce the PWA model. Next, we tackle the identification method. We treat the fuzzy clustering algorithm, deal with the projections of the fuzzy clusters into the input space of the PWA model and explain the estimation of the parameters of the PWA model by means of a modified least-squares method. Furthermore, we verify the usability of the proposed identification approach on a hybrid nonlinear batch reactor example. The result suggest that the batch reactor can be efficiently identified and thus formulated as a PWA model, which can eventually be used for model predictive control purposes.
Abstract: In this paper, we seek to determine one reasonable
local hub port and optimal routes for a containership fleet,
performing pick-ups and deliveries, between the hub and spoke ports
in a same region. The relationship between a hub port, and traffic in
feeder lines is analyzed. A new network planning method is proposed,
an integrated hub port location and route design, a capacitated vehicle
routing problem with pick-ups, deliveries and time deadlines are
formulated and solved using an improved genetic algorithm for
positioning the hub port and establishing routes for a containership
fleet. Results on the performance of the algorithm and the feasibility
of the approach show that a relatively small fleet of containerships
could provide efficient services within deadlines.
Abstract: This article makes and attempt to disclose the
dynamics of development of social interactions in an aggravated
environment in relation to the distinctive features of religious wars
and their negative impact to the society. Crisis situations that took
place in all spheres of social life are described, on the grounds of
which the author comes to specific conclusions.
Abstract: Results in one field necessarily give insight into the
others, and all have much potential for scientific and technological
application. The Hadamard-transform technique once been applied to
the spectrometry also has its use in the SNR Enhancement of OTDR.
In this report, a new set of code (Simplex-codes) is discussed and
where the addition gain of SNR come from is implied.
Abstract: The study was conducted to investigate the profile of
hepatitis in Kingdom of Saudi Arabia, and to determine which age
group hepatitis viruses most commonly infect. The epidemiology of
viral hepatitis in Saudi Arabia has undergone major changes,
concurrent with major socioeconomic developments over the last two
to three decades. This disease represents a major public health
problem in Saudi Arabia resulting in the need for considerable
healthcare resources. A retrospective cross sectional analysis of the
reported cases of viral hepatitis was conducted based on the reports
of The Ministry of Health in Saudi Arabia about Hepatitis A, B and C
infections in all regions from the period of January 2006 to December
2010. The study demonstrated that incidence of viral Hepatitis is
decreasing, except for Hepatitis B that showed minimal increase. Of
hepatitis A, B, and C, Hepatitis B virus (HBV) was the most
predominant type, accounting for (53%) of the cases, followed by
Hepatitis C virus (HCV) (30%) and HAV (17%). HAV infection
predominates in children (5–14 years) with 60% of viral hepatitis
cases, HBV in young adults (15–44 years) with 69% of viral hepatitis
cases, and HCV in older adults (>45 years) with 59% of viral
hepatitis cases. Despite significant changes in the prevalence of viral
hepatitis A, B and C, it remains a major public health problem in
Saudi Arabia; however, it showed a significant decline in the last two
decades that could be attributed to the vaccination programs and the
improved health facilities. Further researches are needed to identify
the risk factors making a specific age group or a specific region in
Saudi Arabia targeted for a specific type of hepatitis viruses.
Abstract: Target tracking and localization are important applications
in wireless sensor networks. In these applications, sensor nodes
collectively monitor and track the movement of a target. They have
limited energy supplied by batteries, so energy efficiency is essential
for sensor networks. Most existing target tracking protocols need to
wake up sensors periodically to perform tracking. Some unnecessary
energy waste is thus introduced. In this paper, an energy efficient
protocol for target localization is proposed. In order to preserve
energy, the protocol fixes the number of sensors for target tracking,
but it retains the quality of target localization in an acceptable
level. By selecting a set of sensors for target localization, the other
sensors can sleep rather than periodically wake up to track the target.
Simulation results show that the proposed protocol saves a significant
amount of energy and also prolongs the network lifetime.
Abstract: Fourier transform infrared (FT-IR) spectroscopic imaging
is an emerging technique that provides both chemically and
spatially resolved information. The rich chemical content of data
may be utilized for computer-aided determinations of structure and
pathologic state (cancer diagnosis) in histological tissue sections for
prostate cancer. FT-IR spectroscopic imaging of prostate tissue has
shown that tissue type (histological) classification can be performed to
a high degree of accuracy [1] and cancer diagnosis can be performed
with an accuracy of about 80% [2] on a microscopic (≈ 6μm)
length scale. In performing these analyses, it has been observed
that there is large variability (more than 60%) between spectra from
different points on tissue that is expected to consist of the same
essential chemical constituents. Spectra at the edges of tissues are
characteristically and consistently different from chemically similar
tissue in the middle of the same sample. Here, we explain these
differences using a rigorous electromagnetic model for light-sample
interaction. Spectra from FT-IR spectroscopic imaging of chemically
heterogeneous samples are different from bulk spectra of individual
chemical constituents of the sample. This is because spectra not
only depend on chemistry, but also on the shape of the sample.
Using coupled wave analysis, we characterize and quantify the nature
of spectral distortions at the edges of tissues. Furthermore, we
present a method of performing histological classification of tissue
samples. Since the mid-infrared spectrum is typically assumed to
be a quantitative measure of chemical composition, classification
results can vary widely due to spectral distortions. However, we
demonstrate that the selection of localized metrics based on chemical
information can make our data robust to the spectral distortions
caused by scattering at the tissue boundary.
Abstract: Ramadan requires individuals to abstain from food and fluid intake between sunrise and sunset; physiological considerations predict that poorer mood, physical performance and mental performance will result. In addition, any difficulties will be worsened because preparations for fasting and recovery from it often mean that nocturnal sleep is decreased in length, and this independently affects mood and performance.
A difficulty of interpretation in many studies is that the observed changes could be due to fasting but also to the decreased length of sleep and altered food and fluid intakes before and after the daytime fasting. These factors were separated in this study, which took place over three separate days and compared the effects of different durations of fasting (4, 8 or 16h) upon a wide variety of measures (including subjective and objective assessments of performance, body composition, dehydration and responses to a short bout of exercise) - but with an unchanged amount of nocturnal sleep, controlled supper the previous evening, controlled intakes at breakfast and daytime naps not being allowed. Many of the negative effects of fasting observed in previous studies were present in this experiment also. These findings indicate that fasting was responsible for many of the changes previously observed, though some effect of sleep loss, particularly if occurring on successive days (as would occur in Ramadan) cannot be excluded.
Abstract: Since injection engines have a considerable portion, in
consumption of energy and environmental pollution, using an
alternative source of energy with lower pollutant effects in this
regard is necessary.
Biodiesel fuel is a suitable alternative for gasoline in diesel
engines.
In this research the property of biodiesel, the function and the
pollution effects of diesel engine, when using 100% biodiesel, using
100% gasoline and mixing ratio of both fuels for comparing them,
have been investigated.
The researches have shown, using biodiesel fuel in prevalent
diesel engine, will reduce the pollutants such as Co, half burned
carbohydrate and suspended particles and a little increase in
oxidation will achieve while power consumption, particularly fuel
and thermal efficiency of diesel fuel has the same.
Abstract: Numerical analysis for the aerodynamic characteristics
of the WIG (wing-in ground effect) craft with highly cambered and
aspect ratio of one is performed to predict the ground effect for the
case of with- and without- lower-extension endplate. The analysis is
included varying angles of attack from 0 to10 deg. and ground
clearances from 5% of chord to 50%. Due to the ground effect, the lift
by rising in pressure on the lower surface is increased and the
influence of wing-tip vortices is decreased. These two significant
effects improve the lift-drag ratio. On the other hand, the endplate
prevents the high-pressure air escaping from the air cushion at the
wing tip and causes to increase the lift and lift-drag ratio further. It is
found from the visualization of computation results that two wing-tip
vortices are generated from each surface of the wing tip and their
strength are weak and diminished rapidly. Irodov-s criteria are also
evaluated to investigate the static height stability. The comparison of
Irodov-s criteria shows that the endplate improves the deviation of the
static height stability with respect to pitch angles and heights. As the
results, the endplate can improve the aerodynamic characteristics and
static height stability of wings in ground effect, simultaneously.
Abstract: A data cutting and sorting method (DCSM) is proposed
to optimize the performance of data mining. DCSM reduces the
calculation time by getting rid of redundant data during the data
mining process. In addition, DCSM minimizes the computational units
by splitting the database and by sorting data with support counts. In the
process of searching for the relationship between metabolic syndrome
and lifestyles with the health examination database of an electronics
manufacturing company, DCSM demonstrates higher search
efficiency than the traditional Apriori algorithm in tests with different
support counts.
Abstract: The purpose of this paper is to investigate the adjust-
ment of solar shading devices in office buildings in two different
seasons by occupants, and its influence on the lighting control and
indoor illuminance levels. The results show that occupants take
inappropriate measures both in reducing solar radiation in summer
and in admitting solar gains in winter, resulting in an increase in
lighting energy and a reduction in indoor illuminance. Therefore,
movable shading devices, controlled automatically, are suitable for
building applications to reduce energy consumption.
Abstract: Rapid urbanization, industrialization and population
growth have led to an increase in number of automobiles that cause
air pollution. It is estimated that road traffic contributes 60% of air
pollution in urban areas. A case by case assessment is required to
predict the air quality in urban situations, so as to evolve certain
traffic management measures to maintain the air quality levels with
in the tolerable limits. Calicut city in the state of Kerala, India has
been chosen as the study area. Carbon Monoxide (CO) concentration
was monitored at 15 links in Calicut city and air quality performance
was evaluated over each link. The CO pollutant concentration values
were compared with the National Ambient Air Quality Standards
(NAAQS), and the CO values were predicted by using CALINE4 and
IITLS and Linear regression models. The study has revealed that
linear regression model performs better than the CALINE4 and
IITLS models. The possible association between CO pollutant
concentration and traffic parameters like traffic flow, type of vehicle,
and traffic stream speed was also evaluated.
Abstract: Documents clustering become an essential technology
with the popularity of the Internet. That also means that fast and
high-quality document clustering technique play core topics. Text
clustering or shortly clustering is about discovering semantically
related groups in an unstructured collection of documents. Clustering
has been very popular for a long time because it provides unique
ways of digesting and generalizing large amounts of information.
One of the issues of clustering is to extract proper feature (concept)
of a problem domain. The existing clustering technology mainly
focuses on term weight calculation. To achieve more accurate
document clustering, more informative features including concept
weight are important. Feature Selection is important for clustering
process because some of the irrelevant or redundant feature may
misguide the clustering results. To counteract this issue, the proposed
system presents the concept weight for text clustering system
developed based on a k-means algorithm in accordance with the
principles of ontology so that the important of words of a cluster can
be identified by the weight values. To a certain extent, it has resolved
the semantic problem in specific areas.
Abstract: This paper reviews the objectives, methods and results of previous studies on biodrying of solid waste in several countries. Biodrying of solid waste is a novel technology in developing countries such as in Malaysia where high moisture content in organic waste makes the segregation process for recycling purposes complicated and diminishes the calorific value for the use of fuel source. In addition, the high moisture content also encourages the breeding of vectors and disease-bearing animals. From the laboratory results, the average moisture content of organic waste, paper, plastics and metals are 58.17%, 37.93%, 29.79% and 1.03% respectively for UKM campus. Biodrying of solid waste is a simple method of waste treatment as well as a cost-efficient technology to dry the solid waste. The process depends on temperature monitoring and air flow control along with the natural biodegradable process of organic waste. This review shows that the biodrying of solid waste method has high potential in treatment and recycling of solid waste, be useful for biodrying study and implementation in Malaysia.
Abstract: We present the development of a new underwater laser
cutting process in which a water-jet has been used along with the
laser beam to remove the molten material through kerf. The
conventional underwater laser cutting usually utilizes a high pressure
gas jet along with laser beam to create a dry condition in the cutting
zone and also to eject out the molten material. This causes a lot of gas
bubbles and turbulence in water, and produces aerosols and waste
gas. This may cause contamination in the surrounding atmosphere
while cutting radioactive components like burnt nuclear fuel. The
water-jet assisted underwater laser cutting process produces much
less turbulence and aerosols in the atmosphere. Some amount of
water vapor bubbles is formed at the laser-metal-water interface;
however, they tend to condense as they rise up through the
surrounding water. We present the design and development of a
water-jet assisted underwater laser cutting head and the parametric
study of the cutting of AISI 304 stainless steel sheets with a 2 kW
CW fiber laser. The cutting performance is similar to that of the gas
assist laser cutting; however, the process efficiency is reduced due to
heat convection by water-jet and laser beam scattering by vapor. This
process may be attractive for underwater cutting of nuclear reactor
components.
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: This paper proposes a method, combining color and layout features, for identifying documents captured from low-resolution handheld devices. On one hand, the document image color density surface is estimated and represented with an equivalent ellipse and on the other hand, the document shallow layout structure is computed and hierarchically represented. Our identification method first uses the color information in the documents in order to focus the search space on documents having a similar color distribution, and finally selects the document having the most similar layout structure in the remaining of the search space.