Abstract: Ecological ponds can be a good teaching tool for
science teachers, but they must be built and maintained properly to
provide students with a safe and suitable learning environment.
Hence, many schools do not have the ability to build an ecological
pond. This study used virtual reality technology to develop a webbased
virtual ecological pond. Supported by situated learning theory
and the instructional design of “Aquatic Life" learning unit,
elementary school students can actively explore in the virtual
ecological pond to observe aquatic animals and plants and learn
about the concept of ecological conservation. A teaching experiment
was conducted to investigate the learning effectiveness and
practicability of this instructional design, and the results showed that
students improved a great deal in learning about aquatic life. They
found the virtual ecological pond interesting, easy to operate and
helpful to understanding the aquatic ecological system. Therefore, it
is useful in elementary science education.
Abstract: In a pilot plant scale of a fluidized bed reactor, a
reduction reaction of sodium sulfate by natural gas has been
investigated. Natural gas is applied in this study as a reductant. Feed
density, feed mass flow rate, natural gas and air flow rate
(independent parameters)and temperature of bed and CO
concentration in inlet and outlet of reactor (dependent parameters)
were monitored and recorded at steady state. The residence time was
adjusted close to value of traditional reaction [1]. An artificial neural
network (ANN) was established to study dependency of yield and
carbon gradient on operating parameters. Resultant 97% accuracy of
applied ANN is a good prove that natural gas can be used as a
reducing agent. Predicted ANN model for relation between other
sources carbon gradient (accuracy 74%) indicates there is not a
meaningful relation between other sources carbon variation and
reduction process which means carbon in granule does not have
significant effect on the reaction yield.
Abstract: This paper describes the pipeline architecture of
high-speed modified Booth multipliers. The proposed multiplier
circuits are based on the modified Booth algorithm and the pipeline
technique which are the most widely used to accelerate the
multiplication speed. In order to implement the optimally pipelined
multipliers, many kinds of experiments have been conducted. The
speed of the multipliers is greatly improved by properly deciding the
number of pipeline stages and the positions for the pipeline registers to
be inserted. We described the proposed modified Booth multiplier
circuits in Verilog HDL and synthesized the gate-level circuits using
0.13um standard cell library. The resultant multiplier circuits show
better performance than others. Since the proposed multipliers operate
at GHz ranges, they can be used in the systems requiring very high
performance.
Abstract: Laboratory experiments have been performed to investigate photocatalytic detoxification by using TiO2 photocatalyst for treating dairy effluent. Various operational parameters such as catalyst concentration, initial concentration, angle of tilt of solar flat plate reactor and flow rate were investigated. Results indicated that the photocatalytic detoxification process can efficiently treat dairy effluent. Experimental runs with dairy wastewater can be used to identify the optimum operational parameters to perform wastewater degradation on large scale for recycling purpose. Also effect of two different types of reactors on degradation process was analyzed.
Abstract: Light rail systems have proliferated in Spain in the last decade, following a tendency that is common not only in other European countries but also in other parts of the world. This paper reviews the benefits of light rail systems, both related to environmental issues and mobility issues. It analyses the evolution of light rail projects in Spain and shows that light rail systems in this country have evolved towards an extensive use of public-private partnerships. The analysis of the Spanish projects, however, does not contribute any conclusive evidence about whether public-private partnerships have been more efficient than publicly owned enterprises in building and operating light rail systems.
Abstract: Young patients suffering from Cerebral Palsy are
facing difficult choices concerning heavy surgeries. Diagnosis settled
by surgeons can be complex and on the other hand decision for
patient about getting or not such a surgery involves important
reflection effort. Proposed software combining prediction for
surgeries and post surgery kinematic values, and from 3D model
representing the patient is an innovative tool helpful for both patients
and medicine professionals. Beginning with analysis and
classification of kinematics values from Data Base extracted from
gait analysis in 3 separated clusters, it is possible to determine close
similarity between patients. Prediction surgery best adapted to
improve a patient gait is then determined by operating a suitable
preconditioned neural network. Finally, patient 3D modeling based
on kinematic values analysis, is animated thanks to post surgery
kinematic vectors characterizing the closest patient selected from
patients clustering.
Abstract: An optimal control of Reverse Osmosis (RO) plant is
studied in this paper utilizing the auto tuning concept in conjunction
with PID controller. A control scheme composing an auto tuning
stochastic technique based on an improved Genetic Algorithm (GA) is
proposed. For better evaluation of the process in GA, objective
function defined newly in sense of root mean square error has been
used. Also in order to achieve better performance of GA, more
pureness and longer period of random number generation in operation
are sought. The main improvement is made by replacing the uniform
distribution random number generator in conventional GA technique
to newly designed hybrid random generator composed of Cauchy
distribution and linear congruential generator, which provides
independent and different random numbers at each individual steps in
Genetic operation. The performance of newly proposed GA tuned
controller is compared with those of conventional ones via simulation.
Abstract: With the rapid advanced of technology, the industrial processes become increasingly demanding, from the point of view, power quality and controllability. The advent of multi levels inverters responds partially to these requirements. But actually, the new generation of multi-cells inverters permits to reach more performances, since, it offers more voltage levels. The disadvantage in the increase of voltage levels by the number of cells in cascades is on account of series igbts synchronisation loss, from where, a limitation of cells in cascade to 4. Regarding to these constraints, a new topology is proposed in this paper, which increases the voltage levels of the three-cell inverter from 4 to 8; with the same number of igbts, and using less stored energy in the flaying capacitors. The details of operation and modelling of this new inverter structure are also presented, then tested thanks to a three phase induction motor. KeywordsFlaying capacitors, Multi-cells inverter, pwm, switchers, modelling.
Abstract: The present work deals with the structural analysis of
turbine blades and modeling of turbine blades. A common failure
mode for turbine machines is high cycle of fatigue of compressor and
turbine blades due to high dynamic stresses caused by blade vibration
and resonance within the operation range of the machinery. In this
work, proper damping system will be analyzed to reduce the
vibrating blade. The main focus of the work is the modeling of under
platform damper to evaluate the dynamic analysis of turbine-blade
vibrations. The system is analyzed using Bond graph technique. Bond
graph is one of the most convenient ways to represent a system from
the physical aspect in foreground. It has advantage of putting together
multi-energy domains of a system in a single representation in a
unified manner. The bond graph model of dry friction damper is
simulated on SYMBOLS-shakti® software. In this work, the blades
are modeled as Timoshenko beam. Blade Vibrations under different
working conditions are being analyzed numerically.
Abstract: This paper aims to study the methodology of building the knowledge of planning adequate punches in order to complete the task of strip layout for shearing processes, using progressive dies. The proposed methodology uses die design rules and characteristics of different types of punches to classify them into five groups: prior use (the punches must be used first), posterior use (must be used last), compatible use (may be used together), sequential use (certain punches must precede some others) and simultaneous use (must be used together). With these five groups of punches, the searching space of feasible designs will be greatly reduced, and superimposition becomes a more effective method of punch layout. The superimposition scheme will generate many feasible solutions, an evaluation function based on number of stages, moment balancing and strip stability is developed for helping designers to find better solutions.
Abstract: Collaborative networked learning (hereafter CNL)
was first proposed by Charles Findley in his work “Collaborative
networked learning: online facilitation and software support" as part
of instructional learning for the future of the knowledge worker. His
premise was that through electronic dialogue learners and experts
could interactively communicate within a contextual framework to
resolve problems, and/or to improve product or process knowledge.
Collaborative learning has always been the forefront of educational
technology and pedagogical research, but not in the mainstream of
operations management. As a result, there is a large disparity in the
study of CNL, and little is known about the antecedents of network
collaboration and sharing of information among diverse employees in
the manufacturing environment. This paper presents a model to
bridge the gap between theory and practice. The objective is that
manufacturing organizations will be able to accelerate organizational
learning and sharing of information through various collaborative
Abstract: This work was to study batch biosorption of Pb(II)
ions from aqueous solution by Luffa charcoal. The effect of operating
parameters such as adsorption contact time, initial pH solution and
different initial Pb(II) concentration on the sorption of Pb(II) were
investigated. The results showed that the adsorption of Pb(II) ions
was initially rapid and the equilibrium time was 10 h. Adsorption
kinetics of Pb(II) ions onto Luffa charcoal could be best described by
the pseudo-second order model. At pH 5.0 was favorable for the
adsorption and removal of Pb(II) ions. Freundlich adsorption
isotherm model was better fitted for the adsorption of Pb(II) ions than
Langmuir and Timkin isotherms, respectively. The highest monolayer
adsorption capacity obtained from Langmuir isotherm model was
51.02 mg/g. This study demonstrated that Luffa charcoal could be
used for the removal of Pb(II) ions in water treatment.
Abstract: Frauds in insurance industry are one of the major
sources of operational risk of insurance companies and constitute a
significant portion of their losses. Every reasonable company on the
market aims for improving their processes of uncovering frauds and
invests their resources to reduce them. This article is addressing fraud
management area from the view of extension of existing Business
Intelligence solution. We describe the frame of such solution and
would like to share with readers all benefits brought to insurance
companies by adopting this approach in their fight against insurance
frauds.
Abstract: Fuel cells have become one of the major areas of
research in the academia and the industry. The goal of most fish
farmers is to maximize production and profits while holding labor
and management efforts to the minimum. Risk of fish kills, disease
outbreaks, poor water quality in most pond culture operations,
aeration offers the most immediate and practical solution to water
quality problems encountered at higher stocking and feeding rates.
Many units of aeration system are electrical units so using a
continuous, high reliability, affordable, and environmentally friendly
power sources is necessary. Aeration of water by using PEM fuel cell
power is not only a new application of the renewable energy, but
also, it provides an affordable method to promote biodiversity in
stagnant ponds and lakes. This paper presents a new design and
control of PEM fuel cell powered a diffused air aeration system for a
shrimp farm in Mersa Matruh in Egypt. Also Artificial intelligence
(AI) techniques control is used to control the fuel cell output power
by control input gases flow rate. Moreover the mathematical
modeling and simulation of PEM fuel cell is introduced. A
comparison study is applied between the performance of fuzzy logic
control (FLC) and neural network control (NNC). The results show
the effectiveness of NNC over FLC.
Abstract: Software engineering education not only embraces
technical skills of software development but also necessitates
communication and interaction among learners. In this paper, it is
proposed to adapt the PBL methodology that is especially designed to
be integrated into software engineering classroom in order to promote
collaborative learning environment. This approach helps students
better understand the significance of social aspects and provides a
systematic framework to enhance teamwork skills. The adaptation of
PBL facilitates the transition to an innovative software development
environment where cooperative learning can be actualized.
Abstract: A mathematical model for determining the overall efficiency
of a multistage tractor gearbox including all gear, lubricant,
surface finish related parameters and operating conditions is
presented. Sliding friction, rolling friction and windage losses were
considered as the main sources of power loss in the gearing system. A
computer code in FORTRAN was developed to simulate the model.
Sliding friction contributes about 98% of the total power loss for
gear trains operating at relatively low speeds (less than 2000 rpm
input speed). Rolling frictional losses decrease with increased load
while windage losses are only significant for gears running at very
high speeds (greater than 3000 rpm). The results also showed that the
overall efficiency varies over the path of contact of the gear meshes
ranging between 94% to 99.5%.
Abstract: This paper aims at improving web server performance
by establishing a middleware layer between web and database
servers, which minimizes the overload on the database server. A
middleware system has been developed as a service mainly to
improve the performance. This system manages connection accesses
in a way that would result in reducing the overload on the database
server. In addition to the connection management, this system acts as
an object-oriented model for best utilization of operating system
resources. A web developer can use this Service Broker to improve
web server performance.
Abstract: detecting the deadlock is one of the important
problems in distributed systems and different solutions have been
proposed for it. Among the many deadlock detection algorithms,
Edge-chasing has been the most widely used. In Edge-chasing
algorithm, a special message called probe is made and sent along
dependency edges. When the initiator of a probe receives the probe
back the existence of a deadlock is revealed. But these algorithms are
not problem-free. One of the problems associated with them is that
they cannot detect some deadlocks and they even identify false
deadlocks. A key point not mentioned in the literature is that when
the process is waiting to obtain the required resources and its
execution has been blocked, how it can actually respond to probe
messages in the system. Also the question of 'which process should
be victimized in order to achieve a better performance when multiple
cycles exist within one single process in the system' has received
little attention. In this paper, one of the basic concepts of the
operating system - daemon - will be used to solve the problems
mentioned. The proposed Algorithm becomes engaged in sending
probe messages to the mandatory daemons and collects enough
information to effectively identify and resolve multi-cycle deadlocks
in distributed systems.
Abstract: The aspiration of this research article is to target and
focus the gains of university-Industry (U-I) collaborations and
exploring those hurdles which are the obstacles for attaining these
gains. University-Industry collaborations have attained great
importance since 1980 in USA due to its application in all fields of
life. U-I collaboration is a bilateral process where academia is a
proactive member to make such alliances. Universities want to
ameliorate their academic-base with the technicalities of technobabbles.
U-I collaboration is becoming an essential lane for achieving
innovative goals in this century. Many developed nations have set
successful examples to prove this phenomenon as a catalyst to reduce
costs, efforts and personnel for R&D projects. This study is exploits
amplitudes of UI collaboration incentives in the light of success
stories of developed countries. Many universities in USA, UK,
Canada and various European Countries have been engaged with
enterprises for numerous collaborative agreements. A long list of
strategic and short term R&D projects has been executed in
developed countries to accomplish their intended purposes. Due to
the lack of intentions, genuine research and research-oriented
environment, the mentioned field could not grow very well in
developing countries. During last decade, a new wave of research
has induced the institutes of developing countries to promote R&D
culture especially in Pakistan. Higher Education Commission (HEC)
has initiated many projects and funding supports for universities
which have collaborative intentions with industry.
Findings show that rapid innovation, overwhelm the technological
complexities and articulated intellectual-base are major incentives
which steer both partners to establish faculty-industry alliances. Everchanging
technologies, concerned about intellectual property,
different research environment and culture, research relevancy (Basic
or applied), exposure differences and diversity of knowledge
(bookish or practical) are main barriers to establish and retain joint
ventures. Findings also concluded that, it is dire need to support and
enhance cooperation among academia and industry to promote highly
coordinated research behaviors. Author has proposed a roadmap for
developing countries to promote R&D clusters among faculty and
industry to deal the technological challenges and innovation
complexities. Based on our research findings, Model for R&D
Collaboration for developing countries also have been proposed to
promote articulated R&D environment. If developing countries
follow this phenomenon, rapid innovations can be achieved with
limited R&D budget heads.
Abstract: This paper presents the design of a low power second-order continuous-time sigma-delta modulator for low power
applications. The loop filter of this modulator has been implemented based on the nonlinear transconductance-capacitor (Gm-C) by employing current-mode technique. The nonlinear transconductance uses floating gate MOS (FG-MOS) transistors that operate in weak inversion region. The proposed modulator features low power consumption (