Abstract: This paper presents performance comparison of three estimation techniques used for peak load forecasting in power systems. The three optimum estimation techniques are, genetic algorithms (GA), least error squares (LS) and, least absolute value filtering (LAVF). The problem is formulated as an estimation problem. Different forecasting models are considered. Actual recorded data is used to perform the study. The performance of the above three optimal estimation techniques is examined. Advantages of each algorithms are reported and discussed.
Abstract: The structural stability of the model of a nonelectroneutral current sheath is investigated. The stationary model of a current sheath represents the system of four connected nonlinear differential first-order equations and thus they should manifest structural instability property, i.e. sensitivity to the infinitesimal changes of parameters and starting conditions. Domains of existence of the solutions of current sheath type are found. Those solutions of the current sheath type are realized only in some regions of sevendimensional space of parameters of the problem. The phase volume of those regions is small in comparison with the whole phase volume of the definition range of those parameters. It is shown that the offered model of a nonelectroneutral current sheath is applicable for theoretical interpretation of the bifurcational current sheaths observed in the magnetosphere.
Abstract: It is sometimes difficult to differentiate between
innocent murmurs and pathological murmurs during auscultation. In
these difficult cases, an intelligent stethoscope with decision support
abilities would be of great value. In this study, using a dog model,
phonocardiographic recordings were obtained from 27 boxer dogs
with various degrees of aortic stenosis (AS) severity. As a reference
for severity assessment, continuous wave Doppler was used. The data
were analyzed with recurrence quantification analysis (RQA) with
the aim to find features able to distinguish innocent murmurs from
murmurs caused by AS. Four out of eight investigated RQA features
showed significant differences between innocent murmurs and
pathological murmurs. Using a plain linear discriminant analysis
classifier, the best pair of features (recurrence rate and entropy)
resulted in a sensitivity of 90% and a specificity of 88%. In
conclusion, RQA provide valid features which can be used for
differentiation between innocent murmurs and murmurs caused by
AS.
Abstract: An experiment was implemented in a filed in the south of Morocco to evaluate the effects of domestic treated wastewater use for irrigation of amaranth crop under semi-arid conditions. Three varieties (A0020, A0057 & A211) were tested and irrigated using domestic treated wastewater EC1 (0,92 dS/m) as control, EC3 (3dS/m) and EC6 (6dS/m) obtained by adding sea water. In term of growth, an increase of the EC level of applied irrigation water reduced significantly the plant-s height, leaf area, fresh and dry weight measured at vegetative, flowering and maturity stage for all varieties. Even with the application of the EC6, yields were relatively higher in comparison with the once obtained in normal cultivation conditions. A significant accumulation of nitrate, chloride and sodium in soil layers during the crop cycle was noted. The use of treated waste water for its irrigation is proved to be possible. The variety A211 had showed to be less sensitive to salinity stress and it could be more promising its introduction to study area.
Abstract: Falls are the primary cause of accidents in people over
the age of 65, and frequently lead to serious injuries. Since the early
detection of falls is an important step to alert and protect the aging
population, a variety of research on detecting falls was carried out
including the use of accelerators, gyroscopes and tilt sensors. In
exiting studies, falls were detected using an accelerometer with
errors. In this study, the proposed method for detecting falls was to
use two accelerometers to reject wrong falls detection. As falls are
accompanied by the acceleration of gravity and rotational motion, the
falls in this study were detected by using the z-axial acceleration
differences between two sites. The falls were detected by calculating
the difference between the analyses of accelerometers placed on two
different positions on the chest of the subject. The parameters of the
maximum difference of accelerations (diff_Z) and the integration of
accelerations in a defined region (Sum_diff_Z) were used to form the
fall detection algorithm. The falls and the activities of daily living
(ADL) could be distinguished by using the proposed parameters
without errors in spite of the impact and the change in the positions
of the accelerometers. By comparing each of the axial accelerations,
the directions of falls and the condition of the subject afterwards
could be determined.In this study, by using two accelerometers
without errors attached to two sites to detect falls, the usefulness of
the proposed fall detection algorithm parameters, diff_Z and
Sum_diff_Z, were confirmed.
Abstract: Solidification cracking and hydrogen cracking are some defects generated in the fusion welding of ultrahigh carbon steels. However, friction stir welding (FSW) of such steels, being a solid-state technique, has been demonstrated to alleviate such problems encountered in traditional welding. FSW include different process parameters that must be carefully defined prior processing. These parameters included but not restricted to: tool feed, tool RPM, tool geometry, tool tilt angle. These parameters form a key factor behind avoiding warm holes and voids behind the tool and in achieving a defect-free weld. More importantly, these parameters directly affect the microstructure of the weld and hence the final mechanical properties of weld. For that, 3D finite element (FE) thermo-mechanical model was developed using DEFORM 3D to simulate FSW of carbon steel. At points of interest in the joint, tracking is done for history of critical state variables such as temperature, stresses, and strain rates. Typical results found include the ability to simulate different weld zones. Simulations predictions were successfully compared to experimental FSW tests. It is believed that such a numerical model can be used to optimize FSW processing parameters to favor desirable defect free weld with better mechanical properties.
Abstract: In a recent major industry-supported research and development study, a novel framework was developed and applied for assessment of reliability and quality performance levels in reallife power systems with practical large-scale sizes. The new assessment methodology is based on three metaphors (dimensions) representing the relationship between available generation capacities and required demand levels. The paper shares the results of the successfully completed stud and describes the implementation of the new methodology on practical zones in the Saudi electricity system.
Abstract: Wireless ad hoc nodes are freely and dynamically
self-organize in communicating with others. Each node can act as
host or router. However it actually depends on the capability of
nodes in terms of its current power level, signal strength, number
of hops, routing protocol, interference and others. In this research,
a study was conducted to observe the effect of hops count over
different network topologies that contribute to TCP Congestion
Control performance degradation. To achieve this objective, a
simulation using NS-2 with different topologies have been
evaluated. The comparative analysis has been discussed based on
standard observation metrics: throughput, delay and packet loss
ratio. As a result, there is a relationship between types of topology
and hops counts towards the performance of ad hoc network. In
future, the extension study will be carried out to investigate the
effect of different error rate and background traffic over same
topologies.
Abstract: Unified Theory of Acceptance and Use of Technology
(UTAUT) model has demonstrated the influencing factors for generic
information systems use such as tablet personal computer (TPC) and
mobile communication. However, in the context of digital library
system, there has been very little effort to determine factors affecting
the intention to use digital library based on the UTAUT model. This
paper investigates factors that are expected to influence the intention
of postgraduate students to use digital library based on modified
UTAUT model. The modified model comprises of constructs
represented by several latent variables, namely performance
expectancy (PE), effort expectancy (EE), information quality (IQ)
and service quality (SQ) and moderated by age, gender and
experience in using digital library. Results show that performance
expectancy, effort expectancy and information quality are positively
related to the intention to use digital library, while service quality is
negatively related to the intention to use digital library. Age and
gender have shown no evidence of any significant interactions, while
experience in using digital library significantly interacts with effort
expectancy and intention to use digital library. This has provided the
evidence of a moderating effect of experience in the intention to use
digital library. It is expected that this research will shed new lights
into research of acceptance and intention to use the library in a digital
environment.
Abstract: In this work, we present a comparison between two
techniques of image compression. In the first case, the image is
divided in blocks which are collected according to zig-zag scan. In
the second one, we apply the Fast Cosine Transform to the image,
and then the transformed image is divided in blocks which are
collected according to zig-zag scan too. Later, in both cases, the
Karhunen-Loève transform is applied to mentioned blocks. On the
other hand, we present three new metrics based on eigenvalues for a
better comparative evaluation of the techniques. Simulations show
that the combined version is the best, with minor Mean Absolute
Error (MAE) and Mean Squared Error (MSE), higher Peak Signal to
Noise Ratio (PSNR) and better image quality. Finally, new technique
was far superior to JPEG and JPEG2000.
Abstract: Delayed wound healing in diabetes is primarily
associated with hyperglycemia, over-expression of inflammatory
marker, oxidative stress and delayed collagen synthesis. This
unmanaged wound is producing high economic burden on the
society. Thus research is required to develop new and effective
treatment strategies to deal with this emerging issue. Our present
study incorporates the evaluation of wound healing effects of 50%
ethanol extract of Ocimum sanctum (OSE) in streptozotocin
(45mg/kg)-induced diabetic rats with concurrent wound ulcer. The
animals showing diabetes (Blood glucose level >140 and
Abstract: Over the past few years, companies in developing
countries have implemented enterprise resource planning (ERP)
systems. Regardless of the various benefits of the ERP system, its
adoption and implementation have not been without problems. Many
companies have assigned considerable organizational resources to
their ERP projects, but have encountered unexpected challenges.
Neglecting a number of important factors in ERP projects might lead
to failure instead of success. User satisfaction is among those factors
that has a major influence on ERP implementation success. So, this
paper intends to investigate the key factors that create ERP users-
satisfaction and to discover whether ERP users- satisfaction varies
among different users- profiles. The study was conducted using a
survey questionnaire which was distributed to ERP users in Iranian
organizations. A total of 384 responses were collected and analyzed.
The findings indicated that younger ERP users tend to be more
satisfied with ERP systems. Furthermore, ERP users with more
experiences in IT and also more educated users have more
satisfaction with ERP softwares. However, the study found no
satisfaction differences between men and women users.
Abstract: Effectiveness and efficiency of food distribution is necessary to maintain food security in a region. Food supply varies among regions depending on their production capacity; therefore, it is necessary to regulate food distribution. Sea transportation could play a great role in the food distribution system. To play this role and to support transportation needs in the Eastern Indonesia, sea transportation shall be supported by fleet which is adequate and reliable, both in terms of load and worthiness. This research uses Linear Programming (LP) method to analyze food distribution pattern in order to determine the optimal distribution system. In this research, transshipment points have been selected for regions in one province. Comparison between result of modeling and existing shipping route reveals that from 369 existing routes, 54 routes are used for transporting rice, corn, green bean, peanut, soybean, sweet potato, and cassava.
Abstract: In this paper, a few chattering-free Sliding Mode Controllers (SMC) are proposed to stabilize an Active Magnetic Bearing (AMB) system with gyroscopic effect that is proportional to the rotor speed. The improved switching terms of the controller inherited from the saturation-type function and boundary layer control technique is shown to be able to achieve bounded and asymptotic stability, respectively, while the chattering effect in the input is attenuated. This is proven to be advantageous for AMB system since minimization of chattering results in optimized control effort. The performance of each controller is demonstrated via result of simulation in which the measurement of the total consumed energy and maximum control magnitude of each controller illustrates the effectiveness of the proposed controllers.
Abstract: This paper deals with a novel technique for the
fabrication of Spiral grooves in a dynamic thrust bearing. The main
scheme proposed in this paper is to fabricate the microgrooves using
desktop forming system. This process has advantages compared to the
conventional electro-chemical machining in the viewpoint of a higher
productivity. For this reason, a new testing apparatus is designed and
built for press forming microgrooves on a surface of the thrust bearing.
The material used in this study is sintered Cu-Fe alloy. The effects of
the forming load on the performance of micro press forming are
experimentally investigated. From the experimental results, formed
depths are closed to the target ones with increasing the forming load.
Abstract: Thai language is difficult in all four language skills,
especially reading. The first year students may have different abilities
in reading, so a teacher is required to find out a student’s reading
level so that the teacher can help and support them till they can
develop and resolve each problem themselves. This research is aimed
to study the prosody problem among Thai students and will be
focused on first year Thai students in the second semester. A total of
58 students were involved in this study. Four obstacles were found:
1. Interpretation from what they read and write
2. Incorrectness Pronunciation of Prosody
3. Incorrectness in Rhythm of the Poem
4. Incorrectness of the Thai Poem Pronunciation
Abstract: The Platform Screen Doors improve Indoor Air Quality
(IAQ) in the subway station; however, and the air quality is degraded
in the subway tunnel. CO2 concentration and indoor particulate matter
value are high in the tunnel. The IAQ level in subway tunnel degrades
by increasing the train movements. Air-curtain installation reduces
dusts, particles and moving toxic smokes and permits traffic by
generating virtual wall. The ventilation systems of the subway tunnel
need improvements to have better air-quality. Numerical analyses
might be effective tools analyze the flowfield inside the air-curtain
installed subway tunnel. The ANSYS CFX software is used for steady
computations of the airflow inside the tunnel. The single-track subway
tunnel has the natural shaft, the mechanical shaft, and the PSDs
installed stations. The height and width of the tunnel are 6.0 m and 4.0
m respectively. The tunnel is 400 m long and the air-curtain is installed
at the top of the tunnel. The thickness and the width of the air-curtain
are 0.08 m and 4 m respectively. The velocity of the air-curtain
changes between 20 - 30 m/s. Three cases are analyzed depending on
the installing location of the air-curtain. The discharged-air through
the natural shafts increases as the velocity of the air-curtain increases
when the air-curtain is installed between the mechanical and the
natural shafts. The pollutant-air is exhausted by the mechanical and the
natural shafts and remained air is pushed toward tunnel end. The
discharged-air through the natural shaft is low when the air-curtain
installed before the natural shaft. The mass flow rate decreases in the
tunnel after the mechanical shaft as the air-curtain velocity increases.
The computational results of the air-curtain installed tunnel become
basis for the optimum design study. The air-curtain installing location
is chosen between the mechanical and the natural shafts. The velocity
of the air-curtain is fixed as 25 m/s. The thickness and the blowing
angles of the air-curtain are the design variables for the optimum
design study. The object function of the design optimization is
maximizing the discharged air through the natural shaft.
Abstract: Cement stabilization has been widely used for
improving the strength and stiffness of soft clayey soils. Cement
treated soil specimens used to investigate the stress-strain behaviour in
the laboratory study are usually cured for 7 days. This paper examines
the effects of curing time on the strength and stress strain behaviour of
cement treated marine clay under triaxial loading condition.
Laboratory-prepared cement treated Singapore marine clay with
different mix proportion S-C-W (soil solid-cement solid-water) and
curing time (7 days to 180 days) was investigated through conducting
unconfined compressive strength test and triaxial test. The results
show that the curing time has a significant effect on the unconfined
compressive strength u q , isotropic compression behaviour and stress
strain behaviour. Although the primary yield loci of the cement treated
soil specimens with the same mix proportion expand with curing time,
they are very narrowly banded and have nearly the same shape after
being normalized by isotropic compression primary stress '
py p . The
isotropic compression primary yield stress '
py p was shown to be
linearly related to unconfined compressive strength u q for specimens
with different curing time and mix proportion. The effect of curing
time on the hardening behaviour will diminish with consolidation
stress higher than isotropic compression primary yield stress but its
damping rate is dependent on the cement content.
Abstract: Family structure that is culturally constructed in every
society is the basic unit of social structure. Purpose of the study was
to compare family structure, including marriage, residence, family
size, type, role sharing, authority, and communication patterns
between Muslim and Santal communities in rural Bangladesh. For
this we assumed that family structure with the elements was
significantly different between the two communities in rural
Bangladesh. In so doing, 288 active couples (145 for Muslim and 143
for Santal) selected by cluster random sampling were intensively
interviewed with a semi-structured questionnaire method. The results
of Pearson Chi-Squire Test reveal that there were significant
differences in the family structure followed by the two communities
in the study area. Further cross-cultural study should be done on why
family structure varies between the communities in Bangladesh.
Abstract: In modern era, the biggest challenge facing the
software industry is the upcoming of new technologies. So, the
software engineers are gearing up themselves to meet and manage
change in large software system. Also they find it difficult to deal
with software cognitive complexities. In the last few years many
metrics were proposed to measure the cognitive complexity of
software. This paper aims at a comprehensive survey of the metric of
software cognitive complexity. Some classic and efficient software
cognitive complexity metrics, such as Class Complexity (CC),
Weighted Class Complexity (WCC), Extended Weighted Class
Complexity (EWCC), Class Complexity due to Inheritance (CCI) and
Average Complexity of a program due to Inheritance (ACI), are
discussed and analyzed. The comparison and the relationship of these
metrics of software complexity are also presented.