Abstract: This paper aims to present the design, fabrication and test of a novel piezoelectric actuated, check-valves embedded micropump having the advantages of miniature size, light weight and low power consumption. This device is designed to pump gases and liquids with the capability of performing the self-priming and bubble-tolerant work mode by maximizing the stroke volume of the membrane as well as the compression ratio via minimization of the dead volume of the micropump chamber and channel. By experiment apparatus setup, we can get the real-time values of the flow rate of micropump, the displacement of the piezoelectric actuator and the deformation of the check valve, simultaneously. The micropump with check valve 0.4 mm in thickness obtained higher output performance under the sinusoidal waveform of 120 Vpp. The micropump achieved the maximum pumping rates of 42.2 ml/min and back pressure of 14.0 kPa at the corresponding frequency of 28 and 20 Hz. The presented micropump is able to pump gases with a pumping rate of 196 ml/min at operating frequencies of 280 Hz under the sinusoidal waveform of 120 Vpp.
Abstract: In order to better understand the performance of
screen channel liquid acquisition devices (LADs) in liquid oxygen (LOX), a computational fluid dynamics (CFD) simulation of LOX passing through a LAD screen channel was conducted. In the
simulation, the screen is taken as a 'porous jump' where the pressure
drop across the screen depends on the incoming velocity and is formulated by Δp = Av + Bv2
. The CFD simulation reveals the importance of the pressure losses due to the flow entering from
across the screen and impacting and merging with the channel flow
and the vortices in the channel to the cumulative flow resistance. In fact, both the flow resistance of flows impact and mergence and the
resistance created by vortices are much larger than the friction and dynamic pressure losses in the channel and are comparable to the
flow resistance across the screen. Therefore, these resistances in the
channel must be considered as part of the evaluation for the LAD
channel performance. For proper operation of a LAD in LOX these resistances must be less than the bubble point pressure for the screen
channel in LOX. The simulation also presents the pressure and velocity distributions within the LAD screen channel, expanding the understanding of the fluid flow characteristics within the channel.
Abstract: Adsorption of proteins onto a solid surface is believed to be the initial and controlling step in biofouling. A better knowledge of the fouling process can be obtained by controlling the formation of the first protein layer at a solid surface. A number of methods have been investigated to inhibit adsorption of proteins. In this study, the adsorption kinetics of
Abstract: The migration of a deformable drop in simple shear
flow at finite Reynolds numbers is investigated numerically by
solving the full Navier-Stokes equations using a finite
difference/front tracking method. The objectives of this study are to
examine the effectiveness of the present approach to predict the
migration of a drop in a shear flow and to investigate the behavior of
the drop migration with different drop sizes and non-unity viscosity
ratios. It is shown that the drop deformation depends strongly on the
capillary number, so that; the proper non-dimensional number for the
interfacial tension is the capillary number. The rate of migration
increased with increasing the drop radius. In other words, the
required time for drop migration to the centreline decreases. As the
viscosity ratio increases, the drop rotates more slowly and the
lubrication force becomes stronger. The increased lubrication force
makes it easier for the drop to migrate to the centre of the channel.
The migration velocity of the drop vanishes as the drop reaches the
centreline under viscosity ratio of one and non-unity viscosity ratios.
To validate the present calculations, some typical results are
compared with available experimental and theoretical data.
Abstract: This paper presents a comparative study on dry and wet grinding through experimental investigation in the grinding of CSM glass fibre reinforced polymer laminates using a pink aluminium oxide wheel. Different sets of experiments were performed to study the effects of the independent grinding parameters such as grinding wheel speed, feed and depth of cut on dependent performance criteria such as cutting forces and surface finish. Experimental conditions were laid out using design of experiment central composite design. An effective coolant was sought in this study to minimise cutting forces and surface roughness for GFRP laminates grinding. Test results showed that the use of coolants reduces surface roughness, although not necessarily the cutting forces. These research findings provide useful economic machining solution in terms of optimized grinding conditions for grinding CSM GFRP.
Abstract: Ants are fascinating creatures that demonstrate the
ability to find food and bring it back to their nest. Their ability as a
colony, to find paths to food sources has inspired the development of
algorithms known as Ant Colony Systems (ACS). The principle of
cooperation forms the backbone of such algorithms, commonly used
to find solutions to problems such as the Traveling Salesman
Problem (TSP). Ants communicate to each other through chemical
substances called pheromones. Modeling individual ants- ability to
manipulate this substance can help an ACS find the best solution.
This paper introduces a Dynamic Ant Colony System with threelevel
updates (DACS3) that enhance an existing ACS. Experiments
were conducted to observe single ant behavior in a colony of
Malaysian House Red Ants. Such behavior was incorporated into the
DACS3 algorithm. We benchmark the performance of DACS3 versus
DACS on TSP instances ranging from 14 to 100 cities. The result
shows that the DACS3 algorithm can achieve shorter distance in
most cases and also performs considerably faster than DACS.
Abstract: In this paper, self-starting block hybrid method of
order (5,5,5,5)T is proposed for the solution of the special second
order ordinary differential equations with associated initial or
boundary conditions. The continuous hybrid formulations enable us
to differentiate and evaluate at some grids and off – grid points to
obtain four discrete schemes, which were used in block form for
parallel or sequential solutions of the problems. The computational
burden and computer time wastage involved in the usual reduction of
second order problem into system of first order equations are avoided
by this approach. Furthermore, a stability analysis and efficiency of
the block method are tested on stiff ordinary differential equations,
and the results obtained compared favorably with the exact solution.
Abstract: The performance of ground to deep space optical
communication systems is degraded by distortion of the beam as it
propagates through the turbulent atmosphere. Turbulence causes
fluctuations in the intensity of the received signal which ultimately
affects the acquisition time required to acquire and locate the spaceborne
target using narrow laser beam. In this paper, performance of
free-space optical (FSO) communication system in atmospheric
turbulence has been analyzed in terms of acquisition time for
coherent and non-coherent modulation schemes. Numerical results
presented in graphical and tabular forms show that the acquisition
time increases with the increase in turbulence level. This is true for
both schemes. The BPSK has lowest acquisition time among all
schemes. In non-coherent schemes, M-PPM performs better than the
other schemes. With the increase in M, acquisition time becomes
lower, but at the cost of increase in system complexity.
Abstract: Tufting carpet is a very suitable substrate for growing
microorganism such as pathogenic microbes, due to the direct touch
with human body, long washing periods and laying on the floor; in
fact there are 3 major problems: To risk human health, Prepare bad
odors and Destruction of the products.. In the presented research, for
investigation of presence most common microbes on polyester
tufting, first goods laid in a public place (in the corridor fair) for 30
days and the existence of some microbes were investigate on it with
two methods of enrichment in nutrient environments such as
thioglycolate and noutrunt brath, and shake the dust off the polyester
tufting onto cultivation mediums such as blood agar and noutrunt
agar. After the microorganism colonics are grown, the colonies were
separated and six microbial tests such as cataloes and sitrat were
carried out in five phases on the colonics for identifying the varieties
of bacteria. As a result of tests, 5 type of bacteria, such as
Escherichia coli, staphylococcus saprophytic as were identified. Each
of the mentioned bacteria can be seriously harmful for the heath of
human.
Abstract: This paper presents an algorithm based on the
wavelet decomposition, for feature extraction from the ECG signal
and recognition of three types of Ventricular Arrhythmias using
neural networks. A set of Discrete Wavelet Transform (DWT)
coefficients, which contain the maximum information about the
arrhythmias, is selected from the wavelet decomposition. After that a
novel clustering algorithm based on nature inspired algorithm (Ant
Colony Optimization) is developed for classifying arrhythmia types.
The algorithm is applied on the ECG registrations from the MIT-BIH
arrhythmia and malignant ventricular arrhythmia databases. We
applied Daubechies 4 wavelet in our algorithm. The wavelet
decomposition enabled us to perform the task efficiently and
produced reliable results.
Abstract: Integrins are a large family of multidomain α/β cell
signaling receptors. Some integrins contain an additional inserted I
domain, whose earliest expression appears to be with the chordates,
since they are observed in the urochordates Ciona intestinalis (vase
tunicate) and Halocynthia roretzi (sea pineapple), but not in integrins
of earlier diverging species. The domain-s presence is viewed as a
hallmark of integrins of higher metazoans, however in vertebrates,
there are clearly three structurally-different classes: integrins without
I domains, and two groups of integrins with I domains but separable
by the presence or absence of an additional αC helix. For example,
the αI domains in collagen-binding integrins from Osteichthyes
(bony fish) and all higher vertebrates contain the specific αC helix,
whereas the αI domains in non-collagen binding integrins from
vertebrates and the αI domains from earlier diverging urochordate
integrins, i.e. tunicates, do not. Unfortunately, within the early
chordates, there is an evolutionary gap due to extinctions between the
tunicates and cartilaginous fish. This, coupled with a knowledge gap
due to the lack of complete genomic data from surviving species,
means that the origin of collagen-binding αC-containing αI domains
remains unknown. Here, we analyzed two available genomes from
Callorhinchus milii (ghost shark/elephant shark; Chondrichthyes –
cartilaginous fish) and Petromyzon marinus (sea lamprey;
Agnathostomata), and several available Expression Sequence Tags
from two Chondrichthyes species: Raja erinacea (little skate) and
Squalus acanthias (dogfish shark); and Eptatretus burgeri (inshore
hagfish; Agnathostomata), which evolutionary reside between the
urochordates and osteichthyes. In P. marinus, we observed several
fragments coding for the αC-containing αI domain, allowing us to
shed more light on the evolution of the collagen-binding integrins.
Abstract: Fishing has always been an essential component of
the Polynesians- life. Fishhooks, mostly in pearl shell, found during
archaeological excavations are the artifacts related to this activity the
most numerous. Thanks to them, we try to reconstruct the ancient
techniques of resources exploitation, inside the lagoons and offshore.
They can also be used as chronological and cultural indicators. The
shapes and dimensions of these artifacts allow comparisons and
classifications used in both functional approach and chrono-cultural
perspective. Hence it is very important for the ethno-archaeologists
to dispose of reliable methods and standardized measurement of
these artifacts. Such a reliable objective and standardized method
have been previously proposed. But this method cannot be envisaged
manually because of the very important time required to measure
each fishhook manually and the quantity of fishhooks to measure
(many hundreds). We propose in this paper a detailed acquisition
protocol of fishhooks and an automation of every step of this method.
We also provide some experimental results obtained on the fishhooks
coming from three archaeological excavations sites.
Abstract: Success is a European project that will implement several clean transport offers in three European cities and evaluate the environmental impacts. The goal of these measures is to improve urban mobility or the displacement of residents inside cities. For e.g. park and ride, electric vehicles, hybrid bus and bike sharing etc. A list of 28 criteria and 60 measures has been established for evaluation of these transport projects. The evaluation criteria can be grouped into: Transport, environment, social, economic and fuel consumption. This article proposes a decision support system based that encapsulates a hybrid approach based on fuzzy logic, multicriteria analysis and belief theory for the evaluation of impacts of urban mobility solutions. A web-based tool called DeSSIA (Decision Support System for Impacts Assessment) has been developed that treats complex data. The tool has several functionalities starting from data integration (import of data), evaluation of projects and finishes by graphical display of results. The tool development is based on the concept of MVC (Model, View, and Controller). The MVC is a conception model adapted to the creation of software's which impose separation between data, their treatment and presentation. Effort is laid on the ergonomic aspects of the application. It has codes compatible with the latest norms (XHTML, CSS) and has been validated by W3C (World Wide Web Consortium). The main ergonomic aspect focuses on the usability of the application, ease of learning and adoption. By the usage of technologies such as AJAX (XML and Java Script asynchrones), the application is more rapid and convivial. The positive points of our approach are that it treats heterogeneous data (qualitative, quantitative) from various information sources (human experts, survey, sensors, model etc.).
Abstract: This paper investigates the effects of lubrication on
the quantity of heat emission of two spur gear. System with and
without lubrication effected on the quantity of heat induced on the
gear box (oil - bearings – gears). Both of lubrication and speed of
motor are affected on the performance of gears. Research investigated
the lubrication on the system with and without loading as well as the
wear of gears and bearing's conditions. Gear box investigated
includes the motor, pump, two spur gears, two shafts; speed change
used pulleys and belts. Load used equal one weight ones of gear.
Lubrication mechanism used jet system (upper and lower jet). Gear
box we used system of jet lubrication is perpendicular direction of
the contact line between two teeth. Results appeared in this work that
the lubrication is the vital parameter which is affected on the
performance and durability of gears and bearings. In macroscopic
observation, we noted that damage of bearings happened during the
absence of lubrication as well as abrasive of wear of teeth. Higher
speed of motor without lubrication increased the noise, but in the
presence of lubrication was decreased.
Abstract: This paper used a fuzzy kohonen neural network for medical image segmentation. Image segmentation plays a important role in the many of medical imaging applications by automating or facilitating the diagnostic. The paper analyses the tumor by extraction of the features of (area, entropy, means and standard deviation).These measurements gives a description for a tumor.
Abstract: This paper describes a rapid prototyping (RP)
technology for forming a hydroxyapatite (HA) bone scaffold model.
The HA powder and a silica sol are mixed into bioceramic slurry form
under a suitable viscosity. The HA particles are embedded in the
solidified silica matrix to form green parts via a wide range of process
parameters after processing by selective laser sintering (SLS). The
results indicate that the proposed process was possible to fabricate
multilayers and hollow shell structure with brittle property but
sufficient integrity for handling prior to post-processing. The
fabricated bone scaffold models had a surface finish of 25
Abstract: The use of plastic materials in agriculture causes
serious hazards to the environment. The introduction of biodegradable materials, which can be disposed directly into the soil
can be one possible solution to this problem. In the present research results of experimental tests carried out on biodegradable film
fabricated from natural waste (corn husk) are presented. The film was
characterized by Fourier transform infrared spectroscopy (FTIR),
differential scanning calorimeter (DSC), thermal gravimetric analysis
(TGA) and atomic force microscope (AFM) observation. The film is
shown to be readily degraded within 7-9 months under controlled soil
conditions, indicating a high biodegradability rate. The film
fabricated was use to produce biodegradable pot (BioPot) for
seedlings plantation. The introduction and the expanding use of
biodegradable materials represent a really promising alternative for
enhancing sustainable and environmentally friendly agricultural
activities.
Abstract: Researches on the general rules of temperature field
changing and their effects on the bridge in construction are necessary.
This paper investigated the rules of temperature field changing and its
effects on bridge using onsite measurement and computational
analysis. Guanyinsha Bridge was used as a case study in this research.
The temperature field was simulated in analyses. The effects of certain
boundary conditions such as sun radiance, wind speed, and model
parameters such as heat factor and specific heat on temperature field
are investigated. Recommended values for these parameters are
proposed. The simulated temperature field matches the measured
observations with high accuracy. At the same time, the stresses and
deflections of the bridge computed with the simulated temperature
field matches measured values too. As a conclusion, the temperature
effect analysis of reinforced concrete box girder can be conducted
directly based on the reliable weather data of the concerned area.
Abstract: The excessive use of agricultural pesticides and the
resulting contamination of food and beds of rivers have been a
recurring problem nowadays. Some of these substances can cause
changes in endocrine balance and impair reproductive function of
human and animal population. In the present study, we evaluated the
possible effects of the fungicide cuprous copper oxide Sandoz® on
pregnant Wistar rats. They received a daily oral administration of 103
or 3.103 mg/kg of the fungicide from the 6th to the 15th day of
gestation. On day 21 of gestation, the maternal and fetal toxicity
parameters and indices were determined. The administration of
cuprous oxide (Copper Sandoz) in Wistar rats, the period of
organogenesis, revealed no evidence of maternal toxicity or embryo
at the studied doses.
Abstract: Higher education has an important role to play in
advocating environmentalism. Given this responsibility, the goal of
higher education should therefore be to develop graduates with the
knowledge, skills and values related to environmentalism. However,
research indicates that there is a lack of consciousness amongst
graduates on the need to be more environmentally aware, especially
when it comes to applying the appropriate knowledge and skills
related to environmentalism. Although institutions of higher learning
do include environmental parameters within their undergraduate and
postgraduate academic programme structures, the environmental
boundaries are usually confined to specific engineering majors within
an engineering programme. This makes environmental knowledge,
skills and values exclusive to certain quarters of the higher education
system. The incorporation of environmental literacy within higher
education institutions as a whole is of utmost pertinence if a nation-s
human capital is to be nurtured to become change agents for the
preservation of environment. This paper discusses approaches that
can be adapted by institutions of higher learning to include
environmental literacy within the graduate-s higher learning
experience.