Abstract: The increasing recognition of the need for education to be closely aligned with team playing, project based learning and problem solving approaches has increase the interest in collaborative learning among university and college instructors. Using online collaboration learning in learning can enhance the outcome and achievement of students as well as improve their communication, critical thinking and personnel skills. The current research aims at examining the effect of OCL on the student's achievement at Kingdom of Bahrain. Numbers of objectives were set to achieve the aim of the research include: investigating the current situation regarding the collaborative learning and OCL at the Kingdom of Bahrain by identifying the advantages and effectiveness of OCL as a learning tool over traditional learning, examining the factors that affect OCL as well as examining the impact of OCL on the student's achievement. To achieve these objectives, quantitative method was adopted. Two hundred and thirty one questionnaires were distributed to students in different local and private universities at Kingdom of Bahrain. The findings of the research show that most of the students prefer to use FTFCL in learning and that OCL is already adopted in some universities especially in University of Bahrain. Moreover, the most factors affecting the adopted OCL are perceived readiness, and guidance and support.
Abstract: The trend in the world of Information Technology
(IT) is getting increasingly large and difficult projects rather than
smaller and easier. However, the data on large-scale IT project
success rates provide cause for concern. This paper seeks to answer
why large-scale IT projects are different from and more difficult than
other typical engineering projects. Drawing on the industrial
experience, a compilation of the conditions that influence failure is
presented. With a view to improve success rates solutions are
suggested.
Abstract: The effects of irrigation with dairy factory wastewater
on soil properties were investigated at two sites that had received
irrigation for > 60 years. Two adjoining paired sites that had never
received DFE were also sampled as well as another seven fields from
a wider area around the factory. In comparison with paired sites that
had not received effluent, long-term wastewater irrigation resulted in
an increase in pH, EC, extractable P, exchangeable Na and K and
ESP. These changes were related to the use of phosphoric acid,
NaOH and KOH as cleaning agents in the factory. Soil organic C
content was unaffected by DFE irrigation but the size (microbial
biomass C and N) and activity (basal respiration) of the soil
microbial community were increased. These increases were
attributed to regular inputs of soluble C (e.g. lactose) present as milk
residues in the wastewater. Principal component analysis (PCA) of
the soils data from all 11sites confirmed that the main effects of DFE
irrigation were an increase in exchangeable Na, extractable P and
microbial biomass C, an accumulation of soluble salts and a liming
effect. PCA analysis of soil bacterial community structure, using
PCR-DGGE of 16S rDNA fragments, generally separated individual
sites from one another but did not group them according to irrigation
history. Thus, whilst the size and activity of the soil microbial
community were increased, the structure and diversity of the
bacterial community remained unaffected.
Abstract: Smoke discharging is a main reason of air pollution
problem from industrial plants. The obstacle of a building has an
affect with the air pollutant discharge. In this research, a mathematical
model of the smoke dispersion from two sources and one source with
a structural obstacle is considered. The governing equation of the
model is an isothermal mass transfer model in a viscous fluid. The
finite element method is used to approximate the solutions of the
model. The triangular linear elements have been used for discretising
the domain, and time integration has been carried out by semi-implicit
finite difference method. The simulations of smoke dispersion in
cases of one chimney and two chimneys are presented. The maximum
calculated smoke concentration of both cases are compared. It is then
used to make the decision for smoke discharging and air pollutant
control problems on industrial area.
Abstract: We present here the results for a comparative study of
some techniques, available in the literature, related to the relevance
feedback mechanism in the case of a short-term learning. Only one
method among those considered here is belonging to the data mining
field which is the K-nearest neighbors algorithm (KNN) while the
rest of the methods is related purely to the information retrieval field
and they fall under the purview of the following three major axes:
Shifting query, Feature Weighting and the optimization of the
parameters of similarity metric. As a contribution, and in addition to
the comparative purpose, we propose a new version of the KNN
algorithm referred to as an incremental KNN which is distinct from
the original version in the sense that besides the influence of the
seeds, the rate of the actual target image is influenced also by the
images already rated. The results presented here have been obtained
after experiments conducted on the Wang database for one iteration
and utilizing color moments on the RGB space. This compact
descriptor, Color Moments, is adequate for the efficiency purposes
needed in the case of interactive systems. The results obtained allow
us to claim that the proposed algorithm proves good results; it even
outperforms a wide range of techniques available in the literature.
Abstract: Later marine propeller is the main component of ship
propulsion system. For a non-series propeller, it is difficult to
indicate the open water marine propeller performance without an
experimental study to measure the marine propeller parameters.
In the present study, the open water performance of a non-series
marine propeller has been carried out experimentally. The
geometrical aspects of a commercial non-series marine propeller
have been measured for a propeller blade area ratio of 0.3985. The
measured propeller performance parameters were the thrust and
torque coefficients for different propeller rotational speed and
different water channel flow velocity, then the open water
performance for the propeller has been plotted.
In addition, a direct comparison between the obtained
experimental results and a theoretical study of a B-series marine
propeller of the same blade area ratio has been carried out. A
correction factor has been introduced to apply the operating
conditions of the experimental results to that of the theoretical study
for the studied marine propeller.
Abstract: In this paper, a solution is presented for a robotic
manipulation problem in industrial settings. The problem is sensing
objects on a conveyor belt, identifying the target, planning and
tracking an interception trajectory between end effector and the
target. Such a problem could be formulated as combining object
recognition, tracking and interception. For this purpose, we integrated
a vision system to the manipulation system and employed tracking
algorithms. The control approach is implemented on a real industrial
manipulation setting, which consists of a conveyor belt, objects
moving on it, a robotic manipulator, and a visual sensor above the
conveyor. The trjectory for robotic interception at a rendezvous point
on the conveyor belt is analytically calculated. Test results show that
tracking the raget along this trajectory results in interception and
grabbing of the target object.
Abstract: New advancement of technology and never satisfying demands of the civilization are putting huge pressure on the natural fuel resources and these resources are at a constant threat to its sustainability. To get the best out of the automobile, the optimum balance between performance and fuel economy is important. In the present state of art, either of the above two aspects are taken into mind while designing and development process which puts the other in the loss as increase in fuel economy leads to decrement in performance and vice-versa. In-depth observation of the vehicle dynamics apparently shows that large amount of energy is lost during braking and likewise large amount of fuel is consumed to reclaim the initial state, this leads to lower fuel efficiency to gain the same performance. Current use of Kinetic Energy Recovery System is only limited to sports vehicles only because of the higher cost of this system. They are also temporary in nature as power can be squeezed only during a small time duration and use of superior parts leads to high cost, which results on concentration on performance only and neglecting the fuel economy. In this paper Kinetic Energy Recovery System for storing the power and then using the same while accelerating has been discussed. The major storing element in this system is a Flat Spiral Spring that will store energy by compression and torsion.
The use of spring ensure the permanent storage of energy until used by the driver unlike present mechanical regeneration system in which the energy stored decreases with time and is eventually lost. A combination of internal gears and spur gears will be used in order to make the energy release uniform which will lead to safe usage. The system can be used to improve the fuel efficiency by assisting in overcoming the vehicle’s inertia after braking or to provide instant acceleration whenever required by the driver. The performance characteristics of the system including response time, mechanical efficiency and overall increase in efficiency are demonstrated. This technology makes the KERS (Kinetic Energy Recovery System) more flexible and economical allowing specific application while at the same time increasing the time frame and ease of usage.
Abstract: Curing of paints by exposure to UV radiations is
emerging as one of the best film forming technique as an alternative
to traditional solvent borne oxidative and thermal curing coatings.
The composition and chemistry of UV curable coatings and role of
multifunctional and monofunctional monomers, oligomers, and
photoinitiators have been discussed. The limitations imposed by
thermodynamic equilibrium and tendency for acrylic double bond
polymerizations during synthesis of multifunctional acrylates have
been presented. Aim of present investigation was thus to explore the
reaction variables associated with synthesis of multifunctional
acrylates. Zirconium oxychloride was evaluated as catalyst against
regular acid functional catalyst. The catalyzed synthesis of glyceryl
acrylate and neopentyl glycol acrylate was conducted by variation of
following reaction parameters: two different reactant molar ratios-
1:4 and 1:6; catalyst usage in % by moles on polyol- 2.5, 5.0 and 7.5
and two different reaction temperatures- 45 and 75 0C. The reaction
was monitored by determination of acid value and hydroxy value at
regular intervals, besides TLC, HPLC, and FTIR analysis of
intermediates and products. On the basis of determination of reaction
progress over 1-60 hrs, the esterification reaction was observed to
follow 2nd order kinetics with rate constant varying from 1*10-4 to
7*10-4. The thermal and catalytic components of second order rate
constant and energy of activation were also determined. Uses of
these kinetic and thermodynamic parameters in design of reactor for
manufacture of multifunctional acrylate ester have been presented.
The synthesized multifunctional acrylates were used to formulate and
apply UV curable clear coat followed by determination of curing
characteristics and mechanical properties of cured film. The overall
curing rates less than 05 min. were easily attained indicating
economical viability of radiation curable system due to faster
production schedules
Abstract: A dynamic software risk assessment model is
presented. Analogies between dynamic financial analysis and
software risk assessment models are established and based on these
analogies it suggested that dynamic risk model for software projects
is the way to move forward for the risk assessment of software
project. It is shown how software risk assessment change during
different phases of a software project and hence requires a dynamic
risk assessment model to capture these variations. Further evolution
of dynamic financial analysis models is discussed and mapped to the
evolution of software risk assessment models.
Abstract: This research seeks to investigate the frequency and
profitability of index arbitrage opportunities involving the SET50
futures, SET50 component stocks, and the ThaiDEX SET50 ETF
(ticker symbol: TDEX). In particular, the frequency and profit of
arbitrage are measured in the following three arbitrage tests: (1)
SET50 futures vs. ThaiDEX SET50 ETF, (2) SET50 futures vs.
SET50 component stocks, and (3) ThaiDEX SET50 ETF vs. SET50
component stocks are investigated. For tests (2) and (3), the problems
involve conic optimization and quadratic programming as subproblems.
This research is first to apply conic optimization and
quadratic programming techniques in the context of index arbitrage
and is first to investigate such index arbitrage in the Thai equity and
derivatives markets. Thus, the contribution of this study is twofold.
First, its results would help understand the contribution of the
derivatives securities to the efficiency of the Thai markets. Second,
the methodology employed in this study can be applied to other
geographical markets, with minor adjustments.
Abstract: An alternative approach to the use of Discrete Fourier
Transform (DFT) for Magnetic Resonance Imaging (MRI) reconstruction
is the use of parametric modeling technique. This method
is suitable for problems in which the image can be modeled by
explicit known source functions with a few adjustable parameters.
Despite the success reported in the use of modeling technique as an
alternative MRI reconstruction technique, two important problems
constitutes challenges to the applicability of this method, these are
estimation of Model order and model coefficient determination. In
this paper, five of the suggested method of evaluating the model
order have been evaluated, these are: The Final Prediction Error
(FPE), Akaike Information Criterion (AIC), Residual Variance (RV),
Minimum Description Length (MDL) and Hannan and Quinn (HNQ)
criterion. These criteria were evaluated on MRI data sets based on the
method of Transient Error Reconstruction Algorithm (TERA). The
result for each criterion is compared to result obtained by the use of a
fixed order technique and three measures of similarity were evaluated.
Result obtained shows that the use of MDL gives the highest measure
of similarity to that use by a fixed order technique.
Abstract: The results of an experimental study of the process of
convective and boiling heat transfer in the vessel with stirrer for
smooth and rough ring-shaped pipes are presented. It is established
that creation of two-dimensional artificial roughness on the heated
surface causes the essential (~100%) intensification of convective
heat transfer. In case of boiling the influence of roughness appears on
the initial stage of boiling and in case of fully developed nucleate
boiling there was no intensification of heat transfer. The similitude
equation for calculating convective heat transfer coefficient, which
generalizes well experimental data both for the smooth and the rough
surfaces is proposed.
Abstract: This paper solves the Non Linear Schrodinger
Equation using the Split Step Fourier method for modeling an optical
fiber. The model generates a complex wave of optical pulses and
using the results obtained two graphs namely Loss versus
Wavelength and Dispersion versus Wavelength are generated. Taking
Chromatic Dispersion and Polarization Mode Dispersion losses into
account, the graphs generated are compared with the graphs
formulated by JDS Uniphase Corporation which uses standard values
of dispersion for optical fibers. The graphs generated when compared
with the JDS Uniphase Corporation plots were found to be more or
less similar thus verifying that the model proposed is right.
MATLAB software was used for doing the modeling.
Abstract: Electricity market activities and a growing demand for electricity have led to heavily stressed power systems. This requires operation of the networks closer to their stability limits. Power system operation is affected by stability related problems, leading to unpredictable system behavior. Voltage stability refers to the ability of a power system to sustain appropriate voltage levels through large and small disturbances. Steady-state voltage stability is concerned with limits on the existence of steady-state operating points for the network. FACTS devices can be utilized to increase the transmission capacity, the stability margin and dynamic behavior or serve to ensure improved power quality. Their main capabilities are reactive power compensation, voltage control and power flow control. Among the FACTS controllers, Static Var Compensator (SVC) provides fast acting dynamic reactive compensation for voltage support during contingency events. In this paper, voltage stability assessment with appropriate representations of tap-changer transformers and SVC is investigated. Integrating both of these devices is the main topic of this paper. Effect of the presence of tap-changing transformers on static VAR compensator controller parameters and ratings necessary to stabilize load voltages at certain values are highlighted. The interrelation between transformer off nominal tap ratios and the SVC controller gains and droop slopes and the SVC rating are found. P-V curves are constructed to calculate loadability margins.
Abstract: An HPLC-UV analytical method was developed to
determine ethylenediaminetetraacetic acid (EDTA) in dairy
wastewater and surface water. The optimizing separation was achieved
by reversed–phase ion-pair liquid chromatography on a C18 column
using methanol as mobile phase solvent, tetrabutylammonium bromide
as the ion-pair reagent in pH 3.3 formate buffer solution at a flow rate
of 0.9 mL min-1 with a UV detector at 265 nm. No interference of Ca,
Mg or NO3
- was detected. Method performance was evaluated in terms
of linearity, repeatability and reproducibility. The method detection
limit was 5 μg L-1. The contents of EDTA in dairy effluents were 72 ~
261 μg L-1 at a large dairy site. A change of EDTA concentration was
observed downstream of the dairy effluent discharge, but this was well
under the predicted no effect concentration for aquatic ecosystem.
Abstract: The use of a Geographic Information System (GIS) in
roadway lighting to show the state of street-lighting and nighttime
accident is demonstrated. Geographical maps were generated
showing colored streets based on how much of the street's length is
illuminated. The night to daytime accidents ratio at intersections
were found along with the state of lighting at those intersections.
The result is a method to show the state of street-lighting at roads and
intersections and a quick guide for decision makers to implement
strategies for better street-lighting to reduce night time traffic
accidents in a particular district.
Abstract: The textural parameters, together with appearance and
flavor, are sensory attributes of great importance for the product to be
accepted by the consumer. The objective of the present study was the
evaluation of the textural attributes of Packhams pears in the fresh
state, after drying in a chamber with forced convection at 50ºC,
lyophilized and re-hydrated. In texture analysis it was used the
method of Texture Profile Analysis (TPA). The parameters analyzed
were hardness, cohesiveness, adhesiveness, elasticity and chewiness.
From the results obtained is possible to see that the drying operation
greatly affected some textural properties of the pears, so that the
hardness diminished very much with drying, for both drying
methods.
Abstract: A new automatic system for the recognition and re¬construction of resealed and/or rotated partially occluded objects is presented. The objects to be recognized are described by 2D views and each view is occluded by several half-planes. The whole object views and their visible parts (linear cuts) are then stored in a database. To establish if a region R of an input image represents an object possibly occluded, the system generates a set of linear cuts of R and compare them with the elements in the database. Each linear cut of R is associated to the most similar database linear cut. R is recognized as an instance of the object 0 if the majority of the linear cuts of R are associated to a linear cut of views of 0. In the case of recognition, the system reconstructs the occluded part of R and determines the scale factor and the orientation in the image plane of the recognized object view. The system has been tested on two different datasets of objects, showing good performance both in terms of recognition and reconstruction accuracy.
Abstract: The effect of flooding can be a serious problem for
wheat farmers, even at dry land condition. Amount of flooding
damage depends on duration flooding, developmental stage, wheat
type and variety. Therefore as a factorial experiment in randomized
complete design based on winter bread wheat cultivars (Pishtaz,
Marvdasht, Shiraz, Zarin, Shahriar, C-81-4, Sardari, Agosta seed,
FGS and Azar2) at stages (Non- flooding stress, flooding at tillering
and stem elongation stages for 15 days) carried out in Faculty of
Agriculture, Razi University, Kermanshah, Iran. During flooding,
soil environment of plant roots were water saturated. Analysis of
variance showed that flooding had a significant effect on the number
of grains per spike, grain weight per spike and a grain weight. Hence
flooding reduces the number of grain per spike between 27.1 to 42.5
percent, grain weight per spike between 34.7 to 54.4 percent and
single grain weight between 12.1 to 15.1 percent. Effects of flooding
at the tillering stage reduced higher than stem elongation stage on
studied traits. The result also showed that flooding at tillering stage
delayed spikelet primordial and floret. Between wheat cultivars was
significant for traits, but were different reactions. "Shiraz", "Zarin"
and "Shahriar" had the most no. grain per spike, but "Zarin" and
"Sardari" had the most grain weight per spike and single grain
weight, respectively. Also, interaction between start of flooding and
cultivar was significant.