Abstract: Composite materials have important assets compared
to traditional materials. They bring many functional advantages:
lightness, mechanical resistance and chemical, etc. In the present
study we examine the effect of a circular central notch and a precrack
on the tensile fracture of two woven composite materials. The tensile
tests were applied to a standardized specimen, notched and a
precarcked (orientation of the crack 0°, 45° and 90°). These tensile
tests were elaborated according to an experimental planning design of
the type 23.31 requiring 24 experiments with three repetitions. By the
analysis of regression, we obtained a mathematical model describing
the maximum load according to the influential parameters (hole
diameter, precrack length, angle of a precrack orientation). The
specimens precracked at 90° have a better behavior than those having
a precrack at 45° and still better than those having of the precracks
oriented at 0°. In addition the maximum load is inversely
proportional to the notch size.
Abstract: Two types of commercial cylindrical lithium ion
batteries (Panasonic 3.4 Ah NCR-18650B and Samsung 2.9 Ah
INR-18650), were investigated experimentally. The capacities of these
samples were individually measured using constant current-constant
voltage (CC-CV) method at different ambient temperatures (-10°C,
0°C, 25°C). Their internal resistance was determined by
electrochemical impedance spectroscopy (EIS) and pulse discharge
methods. The cells with different configurations of parallel connection
NCR-NCR, INR-INR and NCR-INR were charged/discharged at the
aforementioned ambient temperatures. The results showed that the
difference of internal resistance between cells much more evident at
low temperatures. Furthermore, the parallel connection of NCR-NCR
exhibits the most uniform temperature distribution in cells at -10°C,
this feature is quite favorable for the safety of the battery pack.
Abstract: Fly ash is an important waste, produced in thermal
power plants which causes very important environmental pollutions.
For this reason the usage and evaluation the fly ash in various areas
are very important. Nearly, 15 million tons/year of fly ash is
produced in Turkey. In this study, usage of fly ash with diatomite and
molasses for heavy metal (Cd) adsorption from wastewater is
investigated. The samples of Seyitomer region fly ash were analyzed
by X-ray fluorescence (XRF) and Scanning Electron Microscope
(SEM) then diatomite (0 and 1% in terms of fly ash, w/w) and
molasses (0-0.75 mL) were pelletized under 30 MPa of pressure for
the usage of cadmium (Cd) adsorption in wastewater. After the
adsorption process, samples of Seyitomer were analyzed using
Optical Emission Spectroscopy (ICP-OES). As a result, it is seen that
the usage of Seyitomer fly ash is proper for cadmium (Cd) adsorption
and an optimum adsorption yield with 52% is found at a compound
with Seyitomer fly ash (10 g), diatomite (0.5 g) and molasses (0.75
mL) at 2.5 h of reaction time, pH:4, 20ºC of reaction temperature and
300 rpm of stirring rate.
Abstract: Recent perceived climate variability raises concerns
with unprecedented hydrological phenomena and extremes.
Distribution and circulation of the waters of the Earth become
increasingly difficult to determine because of additional uncertainty
related to anthropogenic emissions. The world wide observed
changes in the large-scale hydrological cycle have been related to an
increase in the observed temperature over several decades. Although
the effect of change in climate on hydrology provides a general
picture of possible hydrological global change, new tools and
frameworks for modelling hydrological series with nonstationary
characteristics at finer scales, are required for assessing climate
change impacts. Of the downscaling techniques, dynamic
downscaling is usually based on the use of Regional Climate Models
(RCMs), which generate finer resolution output based on atmospheric
physics over a region using General Circulation Model (GCM) fields
as boundary conditions. However, RCMs are not expected to capture
the observed spatial precipitation extremes at a fine cell scale or at a
basin scale. Statistical downscaling derives a statistical or empirical
relationship between the variables simulated by the GCMs, called
predictors, and station-scale hydrologic variables, called predictands.
The main focus of the paper is on the need for using statistical
downscaling techniques for projection of local hydrometeorological
variables under climate change scenarios. The projections can be then
served as a means of input source to various hydrologic models to
obtain streamflow, evapotranspiration, soil moisture and other
hydrological variables of interest.
Abstract: Natural antimicrobials are used to preserve foods that
can be found in plants, animals, and microorganisms. Antimicrobial
substances are natural or artificial agents that produced by
microorganisms or obtained semi/total chemical synthesis are used at
low concentrations to inhibit the growth of other microorganisms.
Food borne pathogens and spoilage microorganisms are inactivated
by the use of antagonistic microorganisms and their metabolites.
Yeasts can produce toxic proteins or glycoproteins (toxins) that cause
inhibition of sensitive bacteria and yeast species. Antimicrobial
substance producing phenotypes belonging different yeast genus
were isolated from different sources. Toxins secreted by many yeast
strains inhibiting the growth of other yeast strains. These strains show
antimicrobial activity, inhibiting the growth of mold and bacteria.
The effect of antimicrobial agents produced by yeasts can be
extremely fast, and therefore may be used in various treatment
procedures. Rapid inhibition of microorganisms is possibly caused by
microbial cell membrane lipopolysaccharide binding and in
activation (neutralization) effect. Antimicrobial agents inhibit the
target cells via different mechanisms of action.
Abstract: Sudoku is a logic-based combinatorial puzzle game
which people in different ages enjoy playing it. The challenging and
addictive nature of this game has made it a ubiquitous game. Most
magazines, newspapers, puzzle books, etc. publish lots of Sudoku
puzzles every day. These puzzles often come in different levels of
difficulty so that all people, from beginner to expert, can play the
game and enjoy it. Generating puzzles with different levels of
difficulty is a major concern of Sudoku designers. There are several
works in the literature which propose ways of generating puzzles
having a desirable level of difficulty. In this paper, we propose a
method based on constraint satisfaction problems to evaluate the
difficulty of the Sudoku puzzles. Then we propose a hill climbing
method to generate puzzles with different levels of difficulty.
Whereas other methods are usually capable of generating puzzles
with only few number of difficulty levels, our method can be used to
generate puzzles with arbitrary number of different difficulty levels.
We test our method by generating puzzles with different levels of
difficulty and having a group of 15 people solve all the puzzles and
recording the time they spend for each puzzle.
Abstract: A method is proposed for stable detection of
seismoacoustic sources in C-OTDR systems that guarantee given
upper bounds for probabilities of type I and type II errors. Properties
of the proposed method are rigorously proved. The results of
practical applications of the proposed method in a real C-OTDRsystem
are presented.
Abstract: An analysis of the Australian Diabetes Screening
Study estimated undiagnosed diabetes mellitus [DM] prevalence in a
high risk general practice based cohort. DM prevalence varied from
9.4% to 18.1% depending upon the diagnostic criteria utilised with
age being a highly significant risk factor. Utilising the gold standard
oral glucose tolerance test, the prevalence of DM was 22-23% in
those aged >= 70 years and
Abstract: Three dimensional non-Interlaced carbon fibre
reinforced silicon carbide (3-D-Cf/SiC) composites with pyrocarbon
interphase were fabricated using isothermal chemical vapor
infiltration (ICVI) combined with polymer impregnation pyrolysis
(PIP) process. Polysilazane (PSZ) is used as a preceramic polymer to
obtain silicon carbide matrix. Thermo gravimetric analysis (TGA),
Infrared spectroscopic analysis (IR) and X-ray diffraction (XRD)
analysis were carried out on PSZ pyrolysed at different temperatures
to understand the pyrolysis and obtaining the optimum pyrolysing
condition to yield β-SiC phase. The density of the composites was
1.94 g cm-3 after the 3-D carbon preform was SiC infiltrated for 280 h
with one intermediate polysilazane pre-ceramic PIP process.
Mechanical properties of the composite materials were investigated
under tensile, flexural, shear and impact loading. The values of
tensile strength were 200 MPa at room temperature (RT) and 195
MPa at 500°C in air. The average RT flexural strength was 243 MPa.
The lower flexural strength of these composites is because of the
porosity. The fracture toughness obtained from single edge notched
beam (SENB) technique was 39 MPa.m1/2. The work of fracture
obtained from the load-displacement curve of SENB test was 22.8
kJ.m-2. The composites exhibited excellent impact resistance and the
dynamic fracture toughness of 44.8 kJ.m-2 is achieved as determined
from instrumented Charpy impact test. The shear strength of the
composite was 93 MPa, which is significantly higher compared 2-D
Cf/SiC composites. Microstructure evaluation of fracture surfaces
revealed the signatures of fracture processes and showed good
support for the higher toughness obtained.
Abstract: Male factor infertility due to endocrine disturbances
such as abnormalities in prolactin levels are encountered in a
significant proportion. This case control study was carried out to
determine the effects of prolactin on the male reproductive tract,
using 200 male white rats. The rats were maintained as the control
group (G1), hypoprolactinaemic group (G2), 3 hyperprolactinaemic
groups induced using oral largactil (G3), low dose fluphenazine (G4)
and high dose fluphenazine (G5). After 100 days, rats were subjected
to serum prolactin (PRL) level measurements and for basic seminal
fluid analysis (BSA). The difference between serum PRL
concentrations of rats in G2, G3, G4 and G5 as compared to the
control group were highly significant by Student’s t-test (p
Abstract: Azadirachta excelsa or locally known as sentang are
frequently used as a traditional medicine by diabetes patients in
Malaysia. However, less attention has been given to their toxicity
effect. Thus, the study is an attempt to examine the protective effect
of A. excelsa on the pancreas and to determine possible toxicity
mediated by the extract. Diabetes was induced experimentally in rats
by high-fat-diet for 16 weeks followed by intraperitoneal injection of
streptozotocin at dosage of 35 mg/kg of body weight. Declination of
the fasting blood glucose level was observed after continuous
administration of A. excelsa for 14 days twice daily. This is due to the
refining structure of the pancreas. However, surprisingly, the plant
extract reduced the leukocytes, erythrocytes, hemoglobin, MCHC and
lymphocytes. In addition, the rat treated with the plant extract
exhibited increment in AST and eosinocytes level. Overall, the
finding shows that A. excelsa possesses antidiabetic activity by
improving the structure of pancreatic islet of Langerhans but
involved in ameliorating of hematology and biochemical parameters.
Abstract: In this study, six bacterial isolates of a slightly
thermophilic organism from the Sg. Klah hot spring, Malaysia were
successfully isolated and designated as M7T55D1, M7T55D2,
M7T55D3, M7T53D1, M7T53D2 and M7T53D3 respectively. The
bacterial isolates were screened for their cellulose hydrolytic ability
on Carboxymethlycellulose agar medium. The isolated bacterial
strains were identified morphologically, biochemically and
molecularly with the aid of 16S rDNA sequencing. All of the bacteria
showed their optimum growth at a slightly alkaline pH of 7.5 with a
temperature of 55°C. All strains were Gram-negative, non-spore
forming type, strictly aerobic, catalase-positive and oxidase-positive
with the ability to produce thermostable cellulase. Based on BLASTn
results, bacterial isolates of M7T55D2 and M7T53D1 gave the
highest homology (97%) with similarity to Tepidimonas ignava while
isolates M7T55D1, M7T55D3, M7T53D2 and M7T53D3 showed
their closest homology (97%-98%) with Tepidimonas thermarum.
These cellulolytic thermophiles might have a commercial potential to
produce valuable thermostable cellulase.
Abstract: Biological conversion of biomass to methane has
received increasing attention in recent years. Grasses have been
explored for their potential anaerobic digestion to methane. In this
review, extensive literature data have been tabulated and classified.
The influences of several parameters on the potential of these
feedstocks to produce methane are presented. Lignocellulosic
biomass represents a mostly unused source for biogas and ethanol
production. Many factors, including lignin content, crystallinity of
cellulose, and particle size, limit the digestibility of the hemicellulose
and cellulose present in the lignocellulosic biomass. Pretreatments
have used to improve the digestibility of the lignocellulosic biomass.
Each pretreatment has its own effects on cellulose, hemicellulose and
lignin, the three main components of lignocellulosic biomass. Solidstate
anaerobic digestion (SS-AD) generally occurs at solid
concentrations higher than 15%. In contrast, liquid anaerobic
digestion (AD) handles feedstocks with solid concentrations between
0.5% and 15%. Animal manure, sewage sludge, and food waste are
generally treated by liquid AD, while organic fractions of municipal
solid waste (OFMSW) and lignocellulosic biomass such as crop
residues and energy crops can be processed through SS-AD. An
increase in operating temperature can improve both the biogas yield
and the production efficiency, other practices such as using AD
digestate or leachate as an inoculant or decreasing the solid content
may increase biogas yield but have negative impact on production
efficiency. Focus is placed on substrate pretreatment in anaerobic
digestion (AD) as a means of increasing biogas yields using today’s
diversified substrate sources.
Abstract: Enzyme activity was evaluated in the intestine of
juvenile dourado (Salminus brasiliensis) fed with diets containing 0,
10 or 20% of lyophilized bovine colostrum (LBC) inclusion for either
30 or 60 days. The intestinal enzymes acid and alkaline phosphatase
(ACP and ALP, respectively), non-specific esterase (NSE), lipase
(LIP), dipeptidyl aminopeptidase IV (DAP IV) and leucine
aminopeptidase (LAP) were studied using histochemistry in four
intestinal segments (S1, S2, S3 and posterior intestine). Weak
proteolitic activity was observed in all intestinal segments for DAP
IV and LAP. The activity of NSE and LIP was also weak in all
intestines, except for the moderate activity of NSE in the S2 of 20%
LBC group after 30 days and in the S1 of 0% LBC group after 60
days. The ACP was detected only in the S2 and S3 of the 10% LBC
group after 30 days. Moderate and strong staining was observed in
the first three intestinal segments for ALP and weak activity in the
posterior intestine. The activity of DAP IV, LAP and ALP were also
present in the cytoplasm of the enterocytes. In the present results,
bovine colostrum feeding did not cause alterations in activity of
intestinal enzymes.
Abstract: The fight against climate change and the replacement
of fossil energies nearing exhaustion gradually emerge as major
societal and economic challenges. It is possible to develop common
dates of low commercial value, and put on the local and international
market a new generation of products with high added values such as
bio ethanol. Besides its use in chemical synthesis, bio ethanol can be
blended with gasoline to produce a clean fuel while improving the
octane.
Abstract: Electronic market place plays an important
intermediary role for connecting dealers and retail customers. The
main aim of this paper is to design a value co-creation model in
used-car auctions. More specifically, the study has been designed in
order to describe the process of value co-creation in used-car auctions,
to explore the co-created values in used-car auctions, and finally
conclude the paper indicating the future research directions. Our
analysis shows that economic values as well as non-economic values
are co-created in used-car auctions. In addition, this paper contributes
to the academic society broadening the view of value co-creation in
service science.
Abstract: Because of high thermal efficiency and low CO2
emission, diesel engines are being used widely in many industrial
fields although it makes many PM and NOx which give both human
health and environment a negative effect. NOx regulations for diesel
engines, however, are being strengthened and it is impossible to meet
the emission standard without NOx reduction devices such as SCR
(Selective Catalytic Reduction), LNC (Lean NOx Catalyst), and LNT
(Lean NOx Trap). Among the NOx reduction devices, urea-SCR
system is known as the most stable and efficient method to solve the
problem of NOx emission. But this device has some issues associated
with the ammonia slip phenomenon which is occurred by shortage of
evaporation and thermolysis time, and that makes it difficult to achieve
uniform distribution of the injected urea in front of monolith.
Therefore, this study has focused on the mixing enhancement between
urea and exhaust gases to enhance the efficiency of the SCR catalyst
equipped in catalytic muffler by changing inlet gas temperature and
spray conditions to improve the spray uniformity of the urea water
solution. Finally, it can be found that various parameters such as inlet
gas temperature and injector and injection angles significantly affect
the evaporation and mixing of the urea water solution with exhaust
gases, and therefore, optimization of these parameters are required.
Abstract: The study examines the influence of marital status on
consumers of products and services using blogs as a source of
information. A pre-designed questionnaire was used to collect the
primary data from the respondents (experiences). Data were collected
from one hundred and eighty seven respondents residing in and
around the Emirates of Sharjah and Dubai of the United Arab
Emirates. The collected data was analyzed with the help of statistical
tools such as averages, percentages, factor analysis, Student’s t-test
and Structural Equation Modelling Technique.
Objectives of the study are to know the reasons how married and
unmarried or single consumers of products and services are
motivated to use blogs as a source of information, to know whether
the consumers of products and services irrespective of their marital
status share their views and experiences with other bloggers and to
know the respondents’ future intentions towards blogging.
The study revealed the following: Majority of the respondents
have the motivation to blog because they are willing to receive
comments on what they post about services, convenience of blogs to
search for information about services and products, by blogging
respondents share information on the symptoms of a disease/ disorder
that may be experienced by someone, helps to share information
about ready to cook mix products and are keen to spend more time
blogging in the future.
Abstract: An extensive amount of work has been done in data
clustering research under the unsupervised learning technique in Data
Mining during the past two decades. Moreover, several approaches
and methods have been emerged focusing on clustering diverse data
types, features of cluster models and similarity rates of clusters.
However, none of the single clustering algorithm exemplifies its best
nature in extracting efficient clusters. Consequently, in order to
rectify this issue, a new challenging technique called Cluster
Ensemble method was bloomed. This new approach tends to be the
alternative method for the cluster analysis problem. The main
objective of the Cluster Ensemble is to aggregate the diverse
clustering solutions in such a way to attain accuracy and also to
improve the eminence the individual clustering algorithms. Due to
the massive and rapid development of new methods in the globe of
data mining, it is highly mandatory to scrutinize a vital analysis of
existing techniques and the future novelty. This paper shows the
comparative analysis of different cluster ensemble methods along
with their methodologies and salient features. Henceforth this
unambiguous analysis will be very useful for the society of clustering
experts and also helps in deciding the most appropriate one to resolve
the problem in hand.
Abstract: In this paper, we present a new maintenance model
for a partially observable system subject to two failure modes,
namely a catastrophic failure and a failure due to the system
degradation. The system is subject to condition monitoring and the
degradation process is described by a hidden Markov model. A
cost-optimal Bayesian control policy is developed for maintaining
the system. The control problem is formulated in the semi-Markov
decision process framework. An effective computational algorithm is
developed, illustrated by a numerical example.