Abstract: A new design of a planar passive T-micromixer with fin-shaped baffles in the mixing channel is presented. The mixing efficiency and the level of pressure loss in the channel have been investigated by numerical simulations in the range of Reynolds number (Re) 1 to 50. A Mixing index (Mi) has been defined to quantify the mixing efficiency, which results over 85% at both ends of the Re range, what demonstrates the micromixer can enhance mixing using the mechanisms of diffusion (lower Re) and convection (higher Re). Three geometric dimensions: radius of baffle, baffles pitch and height of the channel define the design parameters, and the mixing index and pressure loss are the performance parameters used to optimize the micromixer geometry with a multi-criteria optimization method. The Pareto front of designs with the optimum trade-offs, maximum mixing index with minimum pressure loss, is obtained. Experiments for qualitative and quantitative validation have been implemented.
Abstract: The pedagogy project has been proven as an active
learning method, which is used to develop learner-s skills and
knowledge.The use of technology in the learning world, has filed
several gaps in the implementation of teaching methods, and online
evaluation of learners. However, the project methodology presents
challenges in the assessment of learners online.
Indeed, interoperability between E-learning platforms (LMS) is
one of the major challenges of project-based learning assessment.
Firstly, we have reviewed the characteristics of online assessment
in the context of project-based teaching. We addressed the
constraints encountered during the peer evaluation process.
Our approach is to propose a meta-model, which will describe a
language dedicated to the conception of peer assessment scenario in
project-based learning. Then we illustrate our proposal by an
instantiation of the meta-model through a business process in a
scenario of collaborative assessment on line.
Abstract: The benefits of rooftop greenery systems (such as
energy savings, reduction of greenhouse gas emission for mitigating
climate change and maintaining sustainable development, indoor
temperature control etc.) in buildings are well recognized, however
there remains very little research conducted for quantifying the
benefits in subtropical climates such as in Australia. This study
mainly focuses on measuring/determining temperature profile and air
conditioning energy savings by implementing rooftop greenery
systems in subtropical Central Queensland in Australia. An
experimental set-up was installed at Rockhampton campus of Central
Queensland University, where two standard shipping containers (6m
x 2.4m x 2.4m) were converted into small offices, one with green
roof and one without. These were used for temperature, humidity and
energy consumption data collection. The study found that an energy
savings of up to 11.70% and temperature difference of up to 4°C can
be achieved in March in subtropical Central Queensland climate in
Australia. It is expected that more energy can be saved in peak
summer days (December/February) as temperature difference
between green roof and non-green roof is higher in December-
February.
Abstract: Adhesion to the human intestinal cell is considered
as one of the main selection criteria of lactic acid bacteria for
probiotic use. The adhesion ability of two Bifidobacteriums strains
Bifidobacterium longum BB536 and Bifidobacterium
psudocatenulatum G4 was done using HT-29 human epithelium
cell line as in vitro study. Four different level of pH were used 5.6,
5.7, 6.6, and 6.8 with four different times 15, 30, 60, and 120 min.
Adhesion was quantified by counting the adhering bacteria after
Gram staining. The adhesion of B. longum BB536 was higher than
B. psudocatenulatum G4. Both species showed significant
different in the adhesion properties at the factors tested. The
highest adhesion for both Bifidobacterium was observed at 120
min and the low adhesion was in 15 min. The findings of this
study will contribute to the introduction of new effective probiotic
strain for future utilization.
Abstract: Deaths from cardiovascular diseases have decreased substantially over the past two decades, largely as a result of advances in acute care and cardiac surgery. These developments have produced a growing population of patients who have survived a myocardial infarction. These patients need to be continuously monitored so that the initiation of treatment can be given within the crucial golden hour. The available conventional methods of monitoring mostly perform offline analysis and restrict the mobility of these patients within a hospital or room. Hence the aim of this paper is to design a Portable Cardiac Telemedicine System to aid the patients to regain their independence and return to an active work schedule, there by improving the psychological well being. The portable telemedicine system consists of a Wearable ECG Transmitter (WET) and a slightly modified mobile phone, which has an inbuilt ECG analyzer. The WET is placed on the body of the patient that continuously acquires the ECG signals from the high-risk cardiac patients who can move around anywhere. This WET transmits the ECG to the patient-s Bluetooth enabled mobile phone using blue tooth technology. The ECG analyzer inbuilt in the mobile phone continuously analyzes the heartbeats derived from the received ECG signals. In case of any panic condition, the mobile phone alerts the patients care taker by an SMS and initiates the transmission of a sample ECG signal to the doctor, via the mobile network.
Abstract: The paper proposes a new concept in developing
collaborative design system. The concept framework involves
applying simulation of supply chain management to collaborative
design called – 'SCM–Based Design Tool'. The system is developed
particularly to support design activities and to integrate all facilities
together. The system is aimed to increase design productivity and
creativity. Therefore, designers and customers can collaborate by the
system since conceptual design. JAG: Jewelry Art Generator based
on artificial intelligence techniques is integrated into the system.
Moreover, the proposed system can support users as decision tool
and data propagation. The system covers since raw material supply
until product delivery. Data management and sharing information are
visually supported to designers and customers via user interface. The
system is developed on Web–assisted product development
environment. The prototype system is presented for Thai jewelry
industry as a system prototype demonstration, but applicable for
other industry.
Abstract: RF performance of SOI CMOS device has attracted
significant amount of interest recently. In order to improve RF
parameters, Strained Si/Relaxed Si0.8Ge0.2 investigated as a
replacement for Si technology .Enhancement of carrier mobility
associated with strain engineering makes Strained Si a promising
candidate for improving RF performance of CMOS technology.
From the simulation, the cut-off frequency is estimated to be 224
GHZ, whereas in SOI at similar bias is about 188 GHZ. Therefore,
Strained Si exhibits 19% improvement in cut-off frequency over
similar Si counterpart. In this paper, Ion/Ioff ratio is studied as one of
the key parameters in logic and digital application. Strained Si/SiGe
demonstrates better Ion/Ioff characteristic than SOI, in similar channel
length of 100 nm.Another important key analog figures of merit such
as Early Voltage (VEA) ,transconductance vs drain current (gm /Ids)
are studied. They introduce the efficiency of the devices to convert
dc power into ac frequency.
Abstract: The operation performance of a valveless micro-pump
is strongly dependent on the shape of connected nozzle/diffuser and
Reynolds number. The aims of present work are to compare the
performance curves of micropump with the original straight
nozzle/diffuser and contoured nozzle/diffuser under different back
pressure conditions. The tested valveless micropumps are assembled
of five pieces of patterned PMMA plates with hot-embracing
technique. The structures of central chamber, the inlet/outlet
reservoirs and the connected nozzle/diffuser are fabricated with laser
cutting machine. The micropump is actuated with circular-type PZT
film embraced on the bottom of central chamber. The deformation of
PZT membrane with various input voltages is measured with a
displacement laser probe. A simple testing facility is also constructed
to evaluate the performance curves for comparison.
In order to observe the evaluation of low Reynolds number
multiple vortex flow patterns within the micropump during suction
and pumping modes, the unsteady, incompressible laminar
three-dimensional Reynolds-averaged Navier-Stokes equations are
solved. The working fluid is DI water with constant thermo-physical
properties. The oscillating behavior of PZT film is modeled with the
moving boundary wall in way of UDF program. With the dynamic
mesh method, the instants pressure and velocity fields are obtained
and discussed.Results indicated that the volume flow rate is not
monotony increased with the oscillating frequency of PZT film,
regardless of the shapes of nozzle/diffuser. The present micropump
can generate the maximum volume flow rate of 13.53 ml/min when
the operation frequency is 64Hz and the input voltage is 140 volts.
The micropump with contoured nozzle/diffuser can provide 7ml/min
flow rate even when the back pressure is up to 400 mm-H2O. CFD
results revealed that the flow central chamber was occupied with
multiple pairs of counter-rotating vortices during suction and
pumping modes. The net volume flow rate over a complete
oscillating periodic of PZT
Abstract: Ethanol is generally used as a therapeutic reagent against Hepatocellular carcinoma (HCC or hepatoma) worldwide, as it can induce Hepatocellular carcinoma cell apoptosis at low concentration through a multifactorial process regulated by several unknown proteins. This paper provides a simple and available proteomic strategy for exploring differentially expressed proteins in the apoptotic pathway. The appropriate concentrations of ethanol required to induce HepG2 cell apoptosis were first assessed by MTT assay, Gisma and fluorescence staining. Next, the central proteins involved in the apoptosis pathway processs were determined using 2D-PAGE, SDS-PAGE, and bio-software analysis. Finally the downregulation of two proteins, AFP and survivin, were determined by immunocytochemistry and reverse transcriptase PCR (RT-PCR) technology. The simple, useful method demonstrated here provides a new approach to proteomic analysis in key bio-regulating process including proliferation, differentiation, apoptosis, immunity and metastasis.
Abstract: This paper reports work done to improve the modeling of complex processes when only small experimental data sets are available. Neural networks are used to capture the nonlinear underlying phenomena contained in the data set and to partly eliminate the burden of having to specify completely the structure of the model. Two different types of neural networks were used for the application of pulping problem. A three layer feed forward neural networks, using the Preconditioned Conjugate Gradient (PCG) methods were used in this investigation. Preconditioning is a method to improve convergence by lowering the condition number and increasing the eigenvalues clustering. The idea is to solve the modified odified problem M-1 Ax= M-1b where M is a positive-definite preconditioner that is closely related to A. We mainly focused on Preconditioned Conjugate Gradient- based training methods which originated from optimization theory, namely Preconditioned Conjugate Gradient with Fletcher-Reeves Update (PCGF), Preconditioned Conjugate Gradient with Polak-Ribiere Update (PCGP) and Preconditioned Conjugate Gradient with Powell-Beale Restarts (PCGB). The behavior of the PCG methods in the simulations proved to be robust against phenomenon such as oscillations due to large step size.
Abstract: One of the main advantages of the LO paradigm is to
allow the availability of good quality, shareable learning material
through the Web. The effectiveness of the retrieval process requires a
formal description of the resources (metadata) that closely fits the
user-s search criteria; in spite of the huge international efforts in this
field, educational metadata schemata often fail to fulfil this
requirement. This work aims to improve the situation, by the
definition of a metadata model capturing specific didactic features of
shareable learning resources. It classifies LOs into “teacher-oriented"
and “student-oriented" categories, in order to describe the role a LO
is to play when it is integrated into the educational process. This
article describes the model and a first experimental validation process
that has been carried out in a controlled environment.
Abstract: The flash memory has many advantages such as low power consumption, strong shock resistance, fast I/O and non-volatility. And it is increasingly used in the mobile storage device. The YAFFS, one of the NAND flash file system, is widely used in the embedded device. However, the existing YAFFS takes long time to mount the file system because it scans whole spare areas in all pages of NAND flash memory. In order to solve this problem, we propose a new content-based flash file system using a mounting time reduction technique. The proposed method only scans partial spare areas of some special pages by using content-based block management. The experimental results show that the proposed method reduces the average mounting time by 87.2% comparing with JFFS2 and 69.9% comparing with YAFFS.
Abstract: There are three distinct stages in the evolution of
economic thought, namely:
1. in the first stage, the major concern was to accelerate
economic growth with increased availability of material
goods, especially in developing economies with very low
living standards, because poverty eradication meant faster
economic growth.
2. in the second stage, economists made distinction between
growth and development. Development was seen as going
beyond economic growth, and bringing certain changes in
the structure of the economy with more equitable
distribution of the benefits of growth, with the growth
coming automatic and sustained.
3. the third stage is now reached. Our concern is now with
“sustainable development", that is, development not only
for the present but also of the future.
Thus the focus changed from “sustained growth" to “sustained
development". Sustained development brings to the fore the long
term relationship between the ecology and economic development.
Since the creation of UNEP in 1972 it has worked for
development without destruction for environmentally sound and
sustained development. It was realised that the environment cannot
be viewed in a vaccum, it is not separate from development, nor is it
competing. It suggested for the integration of the environment with
development whereby ecological factors enter development planning,
socio-economic policies, cost-benefit analysis, trade, technology
transfer, waste management, educational and other specific areas.
Industrialisation has contributed to the growth of economy of
several countries. It has improved the standards of living of its people
and provided benefits to the society. It has also created in the process
great environmental problems like climate change, forest destruction
and denudation, soil erosion and desertification etc.
On the other hand, industry has provided jobs and improved the
prospects of wealth for the industrialists. The working class
communities had to simply put up with the high levels of pollution in
order to keep up their jobs and also to save their income.
There are many roots of the environmental problem. They may be
political, economic, cultural and technological conditions of the
modern society. The experts concede that industrial growth lies
somewhere close to the heart of the matter. Therefore, the objective
of this paper is not to document all roots of an environmental crisis
but rather to discuss the effects of industrial growth and
development.
We have come to the conclusion that although public intervention
is often unnecessary to ensure that perfectly competitive markets will
function in society-s best interests, such intervention is necessary
when firms or consumers pollute.
Abstract: In a nuclear reactor Loss of Coolant accident (LOCA)
considers wide range of postulated damage or rupture of pipe in the
heat transport piping system. In the case of LOCA with/without
failure of emergency core cooling system in a Pressurised Heavy
water Reactor, the Pressure Tube (PT) temperature could rise
significantly due to fuel heat up and gross mismatch of the heat
generation and heat removal in the affected channel. The extent and
nature of deformation is important from reactor safety point of view.
Experimental set-ups have been designed and fabricated to simulate
ballooning (radial deformation) of PT for 220 MWe IPHWRs.
Experiments have been conducted by covering the CT by ceramic
fibers and then by submerging CT in water of voided PTs. In both
the experiments, it is observed that ballooning initiates at a
temperature around 665´┐¢C and complete contact between PT and
Caldaria Tube (CT) occurs at around 700´┐¢C approximately. The
strain rate is found to be 0.116% per second. The structural integrity
of PT is retained (no breach) for all the experiments. The PT heatup
is found to be arrested after the contact between PT and CT, thus
establishing moderator acting as an efficient heat sink for IPHWRs.
Abstract: Reservoirs with high pressures and temperatures
(HPHT) that were considered to be atypical in the past are now
frequent targets for exploration. For downhole oilfield drilling tools
and components, the temperature and pressure affect the mechanical
strength. To address this issue, a finite element analysis (FEA) for
206.84 MPa (30 ksi) pressure and 165°C has been performed on the
pressure housing of the measurement-while-drilling/logging-whiledrilling
(MWD/LWD) density tool.
The density tool is a MWD/LWD sensor that measures the density
of the formation. One of the components of the density tool is the
pressure housing that is positioned in the tool. The FEA results are
compared with the experimental test performed on the pressure
housing of the density tool. Past results show a close match between
the numerical results and the experimental test. This FEA model can
be used for extreme HPHT and ultra HPHT analyses, and/or optimal
design changes.
Abstract: Nowadays, Gene Ontology has been used widely by many researchers for biological data mining and information retrieval, integration of biological databases, finding genes, and incorporating knowledge in the Gene Ontology for gene clustering. However, the increase in size of the Gene Ontology has caused problems in maintaining and processing them. One way to obtain their accessibility is by clustering them into fragmented groups. Clustering the Gene Ontology is a difficult combinatorial problem and can be modeled as a graph partitioning problem. Additionally, deciding the number k of clusters to use is not easily perceived and is a hard algorithmic problem. Therefore, an approach for solving the automatic clustering of the Gene Ontology is proposed by incorporating cohesion-and-coupling metric into a hybrid algorithm consisting of a genetic algorithm and a split-and-merge algorithm. Experimental results and an example of modularized Gene Ontology in RDF/XML format are given to illustrate the effectiveness of the algorithm.
Abstract: Much research into handwritten Thai character
recognition have been proposed, such as comparing heads of
characters, Fuzzy logic and structure trees, etc. This paper presents a
system of handwritten Thai character recognition, which is based on
the Ant-minor algorithm (data mining based on Ant colony
optimization). Zoning is initially used to determine each character.
Then three distinct features (also called attributes) of each character
in each zone are extracted. The attributes are Head zone, End point,
and Feature code. All attributes are used for construct the
classification rules by an Ant-miner algorithm in order to classify
112 Thai characters. For this experiment, the Ant-miner algorithm is
adapted, with a small change to increase the recognition rate. The
result of this experiment is a 97% recognition rate of the training set
(11200 characters) and 82.7% recognition rate of unseen data test
(22400 characters).
Abstract: Road transportation system is the most important
method of transporting the goods. Considering the most suitable
geographical situation of Iran to transport the goods between Europe
and Asia and placement of this country in direction of international
corridors (east- west) , (north-south) and Asian land transport to
infrastructure development “A.L.T.I.D" and Transport corridor
Europe - Caucasus - Asia “T.R.A.C.E.C.A", noticing the security of
road transportation system in this country is so important. In this
paper the main factors of accidents on the roads of Iran are
categorized regarding the rate of accidents occurred. Then apart from
studying the main reasons of accidents of every category, the main
factors of these events are studied and its strategies in Iran are
introduced.
Abstract: The performance of adaptive beamforming degrades
substantially in the presence of steering vector mismatches. This
degradation is especially severe in the near-field, for the
3-dimensional source location is more difficult to estimate than the
2-dimensional direction of arrival in far-field cases. As a solution, a
novel approach of near-field robust adaptive beamforming (RABF) is
proposed in this paper. It is a natural extension of the traditional
far-field RABF and belongs to the class of diagonal loading
approaches, with the loading level determined based on worst-case
performance optimization. However, different from the methods
solving the optimal loading by iteration, it suggests here a simple
closed-form solution after some approximations, and consequently,
the optimal weight vector can be expressed in a closed form. Besides
simplicity and low computational cost, the proposed approach reveals
how different factors affect the optimal loading as well as the weight
vector. Its excellent performance in the near-field is confirmed via a
number of numerical examples.
Abstract: This Classifying Bird Sounds (chip notes) project-s
purpose is to reduce the unwanted noise from recorded bird sound
chip notes, design a scheme to detect differences and similarities
between recorded chip notes, and classify bird sound chip notes. The
technologies of determining the similarities of sound waves have
been used in communication, sound engineering and wireless sound
applications for many years. Our research is focused on the similarity
of chip notes, which are the sounds from different birds. The program
we use is generated by Microsoft Cµ.