Abstract: Multi-site damage (MSD) has been a challenge to
aircraft, civil and power plant structures. In real life components are subjected to cracking at many vulnerable locations such as the bolt
holes. However, we do not consider for the presence of multiple cracks. Unlike components with a single crack, these components are
difficult to predict. When two cracks approach one another, their
stress fields influence each other and produce enhancing or shielding effect depending on the position of the cracks. In the present study,
numerical studies on fracture analysis have been conducted by using
the developed code based on the modified virtual crack closure integral (MVCCI) technique and finite element analysis (FEA) software ABAQUS for computing SIF of plates with multiple cracks.
Various parametric studies have been carried out and the results have
been compared with literature where ever available and also with the solution, obtained by using ABAQUS. By conducting extensive
numerical studies expressions for SIF have been obtained for collinear cracks and non-aligned cracks.
Abstract: A glider is in essence an unpowered vehicle and in this project we designed and built an oceanic glider, designed to operate underwater. This Glider was designed to collect ocean data such as temperature, pressure and (in future measures physical dimensions of the operating environment) and output this data to an external source. Development of the Oceanic Glider required research into various actuation systems that control buoyancy, pitch and yaw and the dynamics of these systems. It also involved the design and manufacture of the Glider and the design and implementation of a controller that enabled the Glider to navigate and move in an appropriate manner.
Abstract: The contents of nitrates and nitrites were monitored in
15 ground water resources of a selected region earmarked for the
emergency supply of population. The resources have been selected on
the basis of previous assessment of natural conditions and the
exploitation of territory in the infiltration area as well as the
surroundings of water resources. The health risk analysis carried out
in relation to nitrates and nitrites, which were found to be the most
serious water contaminants, proved, that 14 resources met the health
standards in relation to the assessed criterion and could be included in
crisis plans. Water quality of ground resources may be assessed in the
same way with regard to other contaminants.
Abstract: Environmental statistics reveals that the pollution of
acid rain in South Korea is a serious issue. Yet the awareness of people
is low. Even after a gradual decrease of pollutant emission in Korea,
the acidity has not been reduced. There no boundaries in the
atmosphere are set and the influence of the neighboring countries such
as China is apparent. Governmental efforts among China, Japan and
Korea have been made on this issue. However, not much progress has
been observed. Along with the governmental activities, therefore, an
active monitoring of the pollution among the countries and the
promotion of environmental awareness at the civil level including
especially the middle and high schools are highly recommended. It
will be this young generation who will face damaged country as
inheritance not the current generation.
Abstract: This paper dissertates about issues which may occur
after next year will be major part of civil aviation in EU included into
system of Emission trading. This system should help to fight against
global warming and to fulfill Kyoto Protocol commitments of
European countries. Main issues mentioned in this paper are
connected with problem of radiative forcing from emissions and lack
of their monitoring and charging in EU legislative. There are
mentioned main differences between industrial emissions and
emissions form aviation with notification about possible negative
impacts of neglecting these differences. Special attention is dedicated
to risk of possible reverse effect of inclusion aviation in EU ETS,
which may theoretically occur.
Abstract: Currently, web usage make a huge data from a lot of
user attention. In general, proxy server is a system to support web
usage from user and can manage system by using hit rates. This
research tries to improve hit rates in proxy system by applying data
mining technique. The data set are collected from proxy servers in the
university and are investigated relationship based on several features.
The model is used to predict the future access websites. Association
rule technique is applied to get the relation among Date, Time, Main
Group web, Sub Group web, and Domain name for created model.
The results showed that this technique can predict web content for the
next day, moreover the future accesses of websites increased from
38.15% to 85.57 %.
This model can predict web page access which tends to increase
the efficient of proxy servers as a result. In additional, the
performance of internet access will be improved and help to reduce
traffic in networks.
Abstract: The influence of human activities produced by dams
along the river beds is minor, but the location of accumulation of
water directly influences the hydrological regime. The most
important effect of the influence of damming on the way water flows
decreases the frequency of floods. The water rate controls the water
flow of the dams. These natural reservoirs become dysfunctional and,
as a result, a new distribution of flow in the downstream sector,
where maximum flow is, brings about, in this case, higher values. In
addition to fishing, middle and lower courses of rivers located by
accumulation also have a role in mitigating flood waves, thus
providing flood protection. The Vaslui also ensures a good part of the
needs of the town water supply. The most important lake is Solesti,
close to the Vaslui River, opened in 1974. A hydrological regime of
accumulation is related to an anthropogenic and natural drainage
system. The design conditions and their manoeuvres drain or fill the
water courses.
Abstract: Contamination of aromatic compounds in water can
cause severe long-lasting effects not only for biotic organism but also
on human health. Several alternative technologies for remediation of
polluted water have been attempted. One of these is adsorption
process of aromatic compounds by using organic modified clay
mineral. Porous structure of clay is potential properties for molecular
adsorptivity and it can be increased by immobilizing hydrophobic
structure to attract organic compounds. In this work natural
montmorillonite were modified with cetyltrimethylammonium
(CTMA+) and was evaluated for use as adsorbents of aromatic
compounds: benzene, toluene, and 2-chloro phenol in its single and
multicomponent solution by ethanol:water solvent. Preparation of
CTMA-montmorillonite was conducted by simple ion exchange
procedure and characterization was conducted by using x-day
diffraction (XRD), Fourier-transform infra red (FTIR) and gas
sorption analysis. The influence of structural modification of
montmorillonite on its adsorption capacity and adsorption affinity of
organic compound were studied. It was shown that adsorptivity of
montmorillonite was increased by modification associated with
arrangements of CTMA+ in the structure even the specific surface
area of modified montmorillonite was lower than raw
montmorillonite. Adsorption rate indicated that material has affinity
to adsorb compound by following order: benzene> toluene > 2-chloro
phenol. The adsorption isotherms of benzene and toluene showed 1st
order adsorption kinetic indicating a partition phenomenon of
compounds between the aqueous and organophilic CTMAmontmorillonite.
Abstract: A piston cylinder based high pressure differential
thermal analyzer system is developed to investigate phase
transformations, melting, glass transitions, crystallization behavior of
inorganic materials, glassy systems etc., at ambient to 4 GPa and at
room temperature to 1073 K. The pressure is calibrated by the phase
transition of bismuth and ytterbium and temperature is calibrated
by using thermocouple data chart. The system developed is
calibrated using benzoic acid, ammonium nitrate and it has a
pressure and temperature control of ± 8.9 x 10 -4 GPa , ± 2 K
respectively. The phase transition of Asx Te100-x chalcogenides,
ferrous oxide and strontium boride are studied using the
indigenously developed system.
Abstract: Monitoring of ecological systems is one of the major
issues in ecosystem research. The concepts and methodology of
mathematical systems theory provide useful tools to face this
problem. In many cases, state monitoring of a complex ecological
system consists in observation (measurement) of certain state
variables, and the whole state process has to be determined from the
observed data. The solution proposed in the paper is the design of an
observer system, which makes it possible to approximately recover
the state process from its partial observation. The method is
illustrated with a trophic chain of resource – producer – primary
consumer type and a numerical example is also presented.
Abstract: Cerium-doped lanthanum bromide LaBr3:Ce(5%)
crystals are considered to be one of the most advanced scintillator
materials used in PET scanning, combining a high light yield, fast
decay time and excellent energy resolution. Apart from the correct
choice of scintillator, it is also important to optimise the detector
geometry, not least in terms of source-to-detector distance in order to
obtain reliable measurements and efficiency. In this study a
commercially available 25 mm x 25 mm BrilLanCeTM 380 LaBr3: Ce
(5%) detector was characterised in terms of its efficiency at varying
source-to-detector distances. Gamma-ray spectra of 22Na, 60Co, and
137Cs were separately acquired at distances of 5, 10, 15, and 20cm. As
a result of the change in solid angle subtended by the detector, the
geometric efficiency reduced in efficiency with increasing distance.
High efficiencies at low distances can cause pulse pile-up when
subsequent photons are detected before previously detected events
have decayed. To reduce this systematic error the source-to-detector
distance should be balanced between efficiency and pulse pile-up
suppression as otherwise pile-up corrections would need to be
necessary at short distances. In addition to the experimental
measurements Monte Carlo simulations have been carried out for the
same setup, allowing a comparison of results. The advantages and
disadvantages of each approach have been highlighted.
Abstract: Quality of 2D and 3D cross-sectional images produce
by Computed Tomography primarily depend upon the degree of
precision of primary and secondary X-Ray intensity detection.
Traditional method of primary intensity detection is apt to errors.
Recently the X-Ray intensity measurement system along with smart
X-Ray sensors is developed by our group which is able to detect
primary X-Ray intensity unerringly. In this study a new smart X-Ray
sensor is developed using Light-to-Frequency converter TSL230
from Texas Instruments which has numerous advantages in terms of
noiseless data acquisition and transmission. TSL230 construction is
based on a silicon photodiode which converts incoming X-Ray
radiation into the proportional current signal. A current to frequency
converter is attached to this photodiode on a single monolithic CMOS
integrated circuit which provides proportional frequency count to
incoming current signal in the form of the pulse train. The frequency
count is delivered to the center of PICDEM FS USB board with
PIC18F4550 microcontroller mounted on it. With highly compact
electronic hardware, this Demo Board efficiently read the smart
sensor output data. The frequency output approaches overcome
nonlinear behavior of sensors with analog output thus un-attenuated
X-Ray intensities could be measured precisely and better
normalization could be acquired in order to attain high resolution.
Abstract: Concrete performance is strongly affected by the
particle packing degree since it determines the distribution of the
cementitious component and the interaction of mineral particles. By
using packing theory designers will be able to select optimal
aggregate materials for preparing concrete with low cement content,
which is beneficial from the point of cost. Optimum particle packing
implies minimizing porosity and thereby reducing the amount of
cement paste needed to fill the voids between the aggregate particles,
taking also the rheology of the concrete into consideration. For
reaching good fluidity superplasticizers are required. The results from
pilot tests at Luleå University of Technology (LTU) show various
forms of the proposed theoretical models, and the empirical approach
taken in the study seems to provide a safer basis for developing new,
improved packing models.
Abstract: The state-of-the-art Bag of Words model in Content-
Based Image Retrieval has been used for years but the relevance
feedback strategies for this model are not fully investigated. Inspired
from text retrieval, the Bag of Words model has the ability to use the
wealth of knowledge and practices available in text retrieval. We
study and experiment the relevance feedback model in text retrieval
for adapting it to image retrieval. The experiments show that the
techniques from text retrieval give good results for image retrieval
and that further improvements is possible.
Abstract: The use of bioindicators plants (lichens, bryophytes
and Sphagnum....) in monitoring pollution by heavy metals has been
the subject of several works. However, few studies have addressed
the impact of specific type-s pollutants (fertilizers, pesticides.) on
these organisms.
We propose in this work to make the highlighting effect of NPKs
(NPK: nitrogen-phosphate-potassium-sulfate (NP2O5K2O) (15,15,15),
at concentrations of 10, 20, 30 , 40 and 50mM/L) on the activity of
detoxification enzymes (GSH/GST, CAT, APX and MDA) of plant
bioindicators (mosses and lichens) after treatment for 3 and 7 days.
This study shows the important role of the defense system in the
accumulation and tolerance to chemical pollutants through the
activation of enzymatic (GST (glutathione-S-transferase, APX
(ascorbat peroxidase), CAT (catalase)) and nonenzymatic biomarkers
(GSH (glutathione), MDA (malondialdehyde)) against oxidative
stress generated by the NPKs.
Abstract: Larval survey was carried out in 6 localities in the
urban areas (Putrajaya) and suburban areas (Kuala Selangor) from
January until December 2010. A total of 520 representative
households in 6 localities were selected. Breeding habitats were
sampled outdoors in the surroundings of housing areas. The study
indicated that the most predominant species found in both areas was
Aedes albopictus with the gardening utensil as a preferred breeding
microhabitat for Putrajaya, in contrast to the artificial containers for
Kuala Selangor. From a total of 1083 mosquito larvae species, 984
were Aedes albopictus larvae, 67 positive larvae of Aedes aegypti
and 32 of Culex larvae. Aedes Index and Container Index were
elevated in Putrajaya with 13% and 11% respectively which is higher
than the standard given by the Ministry of Health, Malaysia. This
results implicating dengue-sensitive skewed to the urban areas.
Breteau Index result also above the standard in both study locations.
Abstract: Recently, lots of researchers are attracted to retrieving
multimedia database by using some impression words and their values.
Ikezoe-s research is one of the representatives and uses eight pairs of
opposite impression words. We had modified its retrieval interface and
proposed '2D-RIB'. In '2D-RIB', after a retrieval person selects a
single basic music, the system visually shows some other music
around the basic one along relative position. He/she can select one of
them fitting to his/her intention, as a retrieval result. The purpose of
this paper is to improve his/her satisfaction level to the retrieval result
in 2D-RIB. One of our extensions is to define and introduce the
following two measures: 'melody goodness' and 'general acceptance'.
We implement them in different five combinations. According to an
evaluation experiment, both of these two measures can contribute to
the improvement. Another extension is three types of customization.
We have implemented them and clarified which customization is
effective.
Abstract: The primary cause of Total Hip Replacement (THR)
failure for younger patients is aseptic loosening. This complication is
twice more likely to happen in acetabular cup than in femoral stem.
Excessive micromotion between bone and implant will cause
loosening and it depends in patient activities, age and bone. In this
project, the effects of different metal back design of press fit on
osseointegration of the acetabular cup are carried out. Commercial
acetabular cup designs, namely Spiked, Superfix and Quadrafix are
modelled and analyzed using commercial finite element software.
The diameter of acetabular cup is based on the diameter of acetabular
rim to make sure the component fit to the acetabular cavity. A new
design of acetabular cup are proposed and analyzed to get better
osseointegration between the bones and implant interface. Results
shows that the proposed acetabular cup designs are more stable
compared to other designs with respect to stress and displacement
aspects.
Abstract: The present research was designed to investigate the
anti-microbial activity of aristolochic acid from the root of
Aristolochia bracteata. From the methanolic & ethyl extract extracts
of Aristolochia bracteata aristolochic acid I was isolated and
conformed through IR, NMR & MS. The percentage purity of
aristolochic acid I was determined by UV & HPLC method. Antibacterial
activity of extracts of Aristolochia bracteata and the
isolated compound was determined by disc diffusion method. The
results reveled that the isolated aristolochic acid from methanolic
extract was more pure than the compound from ethyl acetate extract.
The various extracts (500μg/disc) of Aristolochia bracteata showed
moderate antibacterial activity with the average zone of inhibition of
7-18 mm by disc diffusion method. Among the extracts, ethyl acetate
& methanol extracts were shown good anti-microbial activity and the
growth of E.coli (18 mm) was strongly inhibited. Microbial assay of
isolated compound (Aristolochic acid I) from ethyl acetate &
methanol extracts were shown good antimicrobial activity and the
zone of inhibition of both at higher concentration 50 μg/ml was
similar with the standard aristolochic acid. It may be concluded that
the isolated compound of aristolochic acid I has good anti-bacterial
activity.
Abstract: Lipases are enzymes particularly amenable for
immobilization by entrapment methods, as they can work equally
well in aqueous or non-conventional media and long-time stability of
enzyme activity and enantioselectivity is needed to elaborate more
efficient bioprocesses. The improvement of Pseudomonas
fluorescens (Amano AK) lipase characteristics was investigated by
optimizing the immobilization procedure in hybrid organic-inorganic
matrices using ionic liquids as additives. Ionic liquids containing a
more hydrophobic alkyl group in the cationic moiety are beneficial
for the activity of immobilized lipase. Silanes with alkyl- or aryl
nonhydrolizable groups used as precursors in combination with
tetramethoxysilane could generate composites with higher
enantioselectivity compared to the native enzyme in acylation
reactions of secondary alcohols. The optimal effect on both activity
and enantioselectivity was achieved for the composite made from
octyltrimethoxysilane and tetramethoxysilane at 1:1 molar ratio (60%
increase of total activity following immobilization and enantiomeric
ratio of 30). Ionic liquids also demonstrated valuable properties as
reaction media for the studied reactions, comparable with the usual
organic solvent, hexane.