Abstract: In this paper, the influence of upstream structures on the flow patternaround and inside the wind-catcher is experimentally investigated by smoke flow visualization techniques. Wind-catchers are an important part of natural ventilation in residential buildings or public places such as shopping centers, libraries, etc. Wind-catchers might be also used in places of high urban densities; hence their potential to provide natural ventilation is dependent on the presence of upstream structures. In this study, the two-sided wind-catcher model was based on a real wind-catcher observed in the city of Yazd, Iran. The present study focuses on the flow patterns around and inside the isolated two-sided wind-catcher, and on a two-sided wind-catcher in the presence of an upstream structure. The results show that the presence of an upstream structure influences the airflow pattern force and direction. Placing a high upstream structure reverses the airflow direction inside the wind-catcher.
Abstract: The hydrogenated amorphous carbon films (α-C:H)
were deposited on p-type Si (100) substrates at different thicknesses by
radio frequency plasma enhanced chemical vapor deposition
technique (rf-PECVD). Raman spectra display asymmetric
diamond-like carbon (DLC) peaks, representative of the α-C:H films.
The decrease of intensity ID/IG ratios revealed the sp3 content arise at
different thicknesses of the α-C:H films. In terms of mechanical
properties, the high hardness and elastic modulus values showed the
elastic and plastic deformation behaviors related to sp3 content in
amorphous carbon films. Electrochemical properties showed that the
α-C:H films exhibited excellent corrosion resistance in air-saturated
3.5 wt.% NaCl solution for pH 2 at room temperature. Thickness
increasing affected the small sp2 clusters in matrix, restricting the
velocity transfer and exchange of electrons. The deposited α-C:H films
exhibited excellent mechanical properties and corrosion resistance.
Abstract: In this paper a novel design of aerostatic thrust bearing
is proposed and is analyzed numerically. The capillary restrictor and
bearing disk are made of elastomer like silicone and PU. The
viscoelasticity of elastomer helps the capillary expand for more air
flux and at the same time, allows conicity of the bearing surface to
form when the air pressure is enhanced. Therefore the bearing has the
better ability of passive compensation. In the present example, as
compared with the typical model, the new designs can nearly double
the load capability and offer four times static stiffness.
Abstract: Two tragic tsunamis that devastated the west coast of
Sumatra Island, Indonesia in 2004 and North East Japan in 2011 had
damaged bridges to various extents. Tsunamis have resulted in the
catastrophic deterioration of infrastructures i.e. coastal structures,
utilities and transportation facilities. A bridge structure performs vital
roles to enable people to perform activities related to their daily needs
and for development. A damaged bridge needs to be repaired
expeditiously. In order to understand the effects of tsunami forces on
bridges, experimental tests are carried out to measure the
characteristics of hydrodynamic force at various wave heights.
Coastal bridge models designed at a 1:40 scale are used in a 24.0 m
long hydraulic flume with a cross section of 1.5 m by 2.0 m. The
horizontal forces and uplift forces in all cases show that forces
increase nonlinearly with increasing wave amplitude.
Abstract: The exposure to outdoor air pollution causes lung
cancer and increases the risk of bladder cancer. Because air pollution
in urban areas is mainly caused by transportation, it is necessary to
evaluate pollutant exhaust emissions from vehicles during their realworld
use. Nevertheless their evaluation and reduction is a key
problem, especially in the cities, that account for more than 50% of
world population.
A particular attention was given to the slope variability along the
streets during each journey performed by the instrumented vehicle.
In this paper we dealt with the problem of describing a
quantitatively approach for the reconstruction of GPS coordinates and
altitude, in the context of correlation study between driving cycles /
emission / geographical location, during an experimental campaign
realized with some instrumented cars.
Finally the slope analysis can be correlated to the emission and
consumption values in a specific road position, and it could be
evaluated its influence on their behaviour.
Abstract: The present study involved analysis of certain
characteristics of the perennial ryegrass (Lolium perenne L.)
genotypes collected from the natural flora of Ankara, and explores a
correlation among them. In order to evaluate the plants for breeding
purpose as per Turkey's environmental conditions, the perennial
ryegrass plants were collected from natural pasture of Ankara in 2004
and were utilized for the study. Seeds of the collected plants were
sown in pots and seedlings were prepared in a greenhouse. In 2005,
the seedlings were transplanted at 50 × 50 cm2 intervals in
Randomized Complete Blocks Design in an experimental field. In
2007 and 2008, data were recorded from the observations and
measurements of 568 perennial ryegrasses. The plant characteristics,
which were investigated, included re-growth time in spring, color,
density, growth habit, tendency to form inflorescence, time of
inflorescence, plant height, length of upper internode, spike length,
leaf length, leaf width, leaf area, leaf shape, number of spikelets per
spike, seed yield per spike and 1000 grain weight and the correlation
analyses were made using this data. Correlation coefficients were
estimated between all paired combinations of the studied traits. The
yield components exhibited varying trends of association among
themselves. Seed yield per spike showed significant and positive
association with the number of spikelets per spike, 1000 grain weight,
plant height, length of upper internode, spike length, leaf length, leaf
width, leaf area and color, but significant and negative association
with the growth habit and re-growth time in spring.
Abstract: Energy consumption and users’ satisfaction were
compared in three LEED certified office buildings in turkey and an
office building in Egypt. The field studies were conducted in summer
2012. The measured environmental parameters in the four buildings
were indoor air temperature, relative humidity, CO2 percentage and
light intensity. The traditional building is located in Smart Village in
Abu Rawash, Cairo, Egypt. The building was studied for 7 days
resulting in 84 responds. The three rated buildings are in Istanbul;
Turkey. A Platinum LEED certified office building is owned by
BASF and gained a platinum certificate for new construction and
major renovation. The building was studied for 3 days resulting in 13
responds. A Gold LEED certified office building is owned by BASF
and gained a gold certificate for new construction and major
renovation. The building was studied for 2 days resulting in 10
responds. A silver LEED certified office building is owned by
Unilever and gained a silver certificate for commercial interiors. The
building was studied for 7 days resulting in 84 responds.
The results showed that all buildings had no significant difference
regarding occupants’ satisfaction with the amount of lighting, noise
level, odor and access to the outdoor view. There was significant
difference between occupants’ satisfaction in LEED certified
buildings and the traditional building regarding the thermal
environment and the perception of the general environment (colors,
carpet and decoration. The findings suggest that careful design could
lead to a certified building that enhances the thermal environment and
the perception of the indoor environment leading to energy
consumption without scarifying occupants’ satisfaction.
Abstract: The biosynthesis of nanoparticles by microorganisms,
on the contrary to chemical synthesis, is an environmentally-friendly
process which has low energy requirements. In this investigation, we
used the microorganism Geobacillus wiegelii, strain GWE1, an
aerobic thermophile belonging to genus Geobacillus, isolated from a
drying oven. This microorganism has the ability to reduce selenite
evidenced by the change of color from colorless to red in the culture.
Elemental analysis and composition of the particles were verified
using transmission electron microscopy and energy-dispersive X-ray
analysis. The nanoparticles have a defined spherical shape and a
selenium elemental state. Previous experiments showed that the
presence of the whole microorganism for the reduction of selenite
was not necessary. The results strongly suggested that an intracellular
NADPH/NADH-dependent reductase mediates selenium
nanoparticles synthesis under aerobic conditions. The enzyme was
purified and identified by mass spectroscopy MALDI-TOF TOF
technique. The enzyme is a 1-pyrroline-5-carboxylate dehydrogenase.
Histograms of nanoparticles sizes were obtained. Size distribution
ranged from 40-160 nm, where 70% of nanoparticles have less than
100 nm in size. Spectroscopic analysis showed that the nanoparticles
are composed of elemental selenium. To analyse the effect of pH in
size and morphology of nanoparticles, the synthesis of them was
carried out at different pHs (4.0, 5.0, 6.0, 7.0, 8.0). For
thermostability studies samples were incubated at different
temperatures (60, 80 and 100 ºC) for 1 h and 3 h. The size of all
nanoparticles was less than 100 nm at pH 4.0; over 50% of
nanoparticles have less than 100 nm at pH 5.0; at pH 6.0 and 8.0 over
90% of nanoparticles have less than 100 nm in size. At neutral pH
(7.0) nanoparticles reach a size around 120 nm and only 20% of them
were less than 100 nm. When looking at temperature effect,
nanoparticles did not show a significant difference in size when they
were incubated between 0 and 3 h at 60 ºC. Meanwhile at 80 °C the
nanoparticles suspension lost its homogeneity. A change in size was
observed from 0 h of incubation at 80ºC, observing a size range
between 40-160 nm, with 20% of them over 100 nm. Meanwhile
after 3 h of incubation at size range changed to 60-180 nm with 50%
of them over 100 nm. At 100 °C the nanoparticles aggregate forming
nanorod structures. In conclusion, these results indicate that is
possible to modulate size and shape of biologically synthesized
nanoparticles by modulating pH and temperature.
Abstract: The purpose of this study was to investigate
perceptions of climate change risk to forest ecosystems and forestbased
communities as well as perceived effectiveness of adaptation
strategies for climate change as well as challenges for adaptation.
Data was gathered using a pre-tested semi-structured questionnaire.
Simple random selection technique was applied. For the majority of
issues, the responses were obtained on multi-point likert scales, and
the scores provided were, in turn, used to estimate the means and
other useful estimates. A composite knowledge index developed
using correct responses to a set of self-rated statements were used to
evaluate the issues. The mean of the knowledge index was 0.64. Also
all respondents recorded values of the knowledge index above 0.25.
Increase forest fire was perceived by respondents as the greatest risk
to forest eco-system. Decrease access to water supplies was perceived
as the greatest risk to livelihoods of forest based communities. The
most effective adaptation strategy relevant to climate change risks to
forest eco-systems and forest based communities livelihoods in
Kathmandu valley in Nepal as perceived by the respondents was
reforestation and afforestation. As well, lack of public awareness was
perceived as the major limitation for climate change adaptation.
However, perceived risks as well as effective adaptation strategies
showed an inconsistent association with knowledge indicators and
social-cultural variables. The results provide useful information to
any party who involve with climate change issues in Nepal, since
such attempts would be more effective once the people’s perceptions
on these aspects are taken into account.
Abstract: In this paper it was examined the influence of margin
regulation on stock market volatility in EU 1993 – 2014. Regulating
margin requirements or haircuts for securities financing transactions
has for a long time been considered as a potential tool to limit the
build-up of leverage and dampen volatility in financial markets. The
margin requirement dictates how much investors can borrow against
these securities. Margin can be an important part of investment.
Using daily and monthly stock returns and there is no convincing
evidence that EU Regulation margin requirements have served to
dampen stock market volatility. In this paper was detected the
expected negative relation between margin requirements and the
amount of margin credit outstanding. Also, it confirmed that changes
in margin requirements by the EU regulation have tended to follow
than lead changes in market volatility. For the analysis have been
used the modified Levene statistics to test whether the standard
deviation of stock returns in the 25, 50 and 100 days preceding
margin changes is the same as that in the succeeding 25, 50 and 100
days. The analysis started in May 1993 when it was first empowered
to set the initial margin requirement and the last sample was in May
2014. To test whether margin requirements influence stock market
volatility over the long term, the sample of stock returns was divided
into 14 periods, according to the 14 changes in margin requirements.
Abstract: The main objective of the study is focused in
producing slag based geopolymer concrete obtained with the addition
of alkali activator. Test results indicated that the reaction of silicates
in slag is based on the reaction potential of sodium hydroxide and the
formation of alumino-silicates. The study also comprises on the
evaluation of the efficiency of polymer reaction in terms of the
strength gain properties for different geopolymer mixtures.
Geopolymer mixture proportions were designed for different binder
to total aggregate ratio (0.3 & 0.45) and fine to coarse aggregate ratio
(0.4 & 0.8). Geopolymer concrete specimens casted with normal
curing conditions reported a maximum 28 days compressive strength
of 54.75 MPa. The addition of glued steel fibres at 1.0% Vf in
geopolymer concrete showed reasonable improvements on the
compressive strength, split tensile strength and flexural properties of
different geopolymer mixtures. Further, comparative assessment was
made for different geopolymer mixtures and the reinforcing effects of
steel fibres were investigated in different concrete matrix.
Abstract: Electricity is recognized as fundamental to
industrialization and improving the quality of life of the people.
Harnessing the immense untapped hydropower potential in Tripura
region opens avenues for growth and provides an opportunity to
improve the well-being of the people of the region, while making
substantial contribution to the national economy. Gumti hydro power
plant generates power to mitigate the crisis of power in Tripura,
India. The first unit of hydro power plant (5MW) was commissioned
in June 1976 & another two units of 5 MW was commissioned
simultaneously. But out of 15MW capacity at present only 8MW-
9MW power is produced from Gumti hydro power plant during rainy
season. But during lean season the production reduces to 0.5MW due
to shortage of water. Now, it is essential to implement some
mitigation measures so that the further atrocities can be prevented
and originality will be possible to restore. The decision making
ability of the Analytic Hierarchy Process (AHP) and Concordance
Analysis Techniques (CAT) are utilized to identify the better decision
or solution to the present problem. Some related attributes are
identified by the method of surveying within the experts and the
available reports and literatures. Similar criteria are removed and
ultimately seven relevant ones are identified. All the attributes are
compared with each other and rated accordingly to their importance
over the other with the help of Pair wise Comparison Matrix. In the
present investigation different mitigation measures are identified and
compared to find the best suitable alternative which can solve the
present uncertainties involving the existence of the Gumti Hydro
Power Plant.
Abstract: Curcuma longa L. (Zingiberaceae), commonly known
as turmeric, has a long history of traditional uses for culinary
purposes as a spice and a food colorant. The present study aimed to
document the ethnobotanical knowledge about Curcuma longa, and
to assess the variation in the herbalists’ experience in Northeastern
Algeria. Data were collected using semi-structured questionnaires
and direct interviews with 30 herbalists. Ethnobotanical indices,
including the fidelity level (FL%), the relative frequency citation
(RFC), and use value (UV) were determined by quantitative methods.
Diversity in the level of knowledge was analyzed using univariate,
non-parametric, and multivariate statistical methods. Three main
categories of uses were recorded for C. longa: for food, for medicine,
and for cosmetic purposes. As a medicine, turmeric was used for the
treatment of gastrointestinal, dermatological, and hepatic diseases.
Medicinal and food uses were correlated with both forms of
preparation (rhizome and powder). The age group did not influence
the use. Multivariate analyses showed a significant variation in
traditional knowledge, associated with the use value, origin, quality,
and efficacy of the drug. The findings suggested that the geographical
origin of C. longa affected the use in Algeria.
Abstract: The use of information and communication
technologies such as computers, mobile phones and the Internet is
becoming prevalent in today’s world; and it is facilitating access to a
vast amount of data, services and applications for the improvement of
people’s lives. However, this prevalence of ICTs is hampered by the
problem of low income levels in developing countries to the point
where people cannot timeously replace or repair their ICT devices
when damaged or lost; and this problem serves as a motivation for
this study whose aim is to examine the perceptions of teachers on the
reliability of cellphones when used for teaching and learning
purposes. The research objectives unfolding this aim are of two
types: Objectives on the selection and design of theories and models,
and objectives on the empirical testing of these theories and models.
The first type of objectives is achieved using content analysis in an
extensive literature survey: and the second type of objectives is
achieved through a survey of high school teachers from the ILembe
and UMgungundlovu districts in the KwaZulu-Natal province of
South Africa. Data collected from this questionnaire based survey is
analysed in SPSS using descriptive statistics and Pearson correlations
after checking the reliability and validity of the questionnaires. The
main hypothesis driving this study is that there is a relationship
between the demographics and the attribution identity of teachers on
one hand, and their perceptions on the reliability of cellphones on the
other hand, as suggested by existing literature; except that attribution
identities are considered in this study under three angles: intention,
knowledge and ability, and action. The results of this study confirm
that the perceptions of teachers on the reliability of cellphones for
teaching and learning are affected by the school location of these
teachers, and by their perceptions on learners’ cellphones usage
intentions and actual use.
Abstract: Self-service technologies (SSTs) make an important
contribution to the daily life of people nowadays. However, the
introduction of SST does not lead to its usage. Thereby, this paper
was an attempt on discovery of the most preferred SST in the
customers’ point of view. To fulfill this aim, the Analytical Hierarchy
Process (AHP) was applied based on Saaty’s questionnaire which
was administered to the customers of e-banking services located in
Golestan providence, northern Iran. This study used qualitative
factors in association with the intention of consumers’ usage of SSTs
to rank three SSTs: ATM, mobile banking and internet banking. The
results showed that mobile banking get the highest weight in
consumers’ point of view. This research can be useful both for
managers and service providers and also for customers who intend to
use e-banking.
Abstract: Drying behavior of blanched sweet potato in a cabinet
dryer using different five air temperatures (40-80°C) and ten sweet
potato varieties sliced to 5mm thickness were investigated. The
drying data were fitted to eight models. The Modified Henderson and
Pabis model gave the best fit to the experimental moisture ratio data
obtained during the drying of all the varieties while Newton (Lewis)
and Wang and Singh models gave the least fit. The values of Deff
obtained for Bophelo variety (1.27 x 10-9 to 1.77 x 10-9 m2/s) was
the least while that of S191 (1.93 x 10-9 to 2.47 x 10-9 m2/s) was the
highest which indicates that moisture diffusivity in sweet potato is
affected by the genetic factor. Activation energy values ranged from
0.27-6.54 kJ/mol. The lower activation energy indicates that drying
of sweet potato slices requires less energy and is hence a cost and
energy saving method. The drying behavior of blanched sweet potato
was investigated in a cabinet dryer. Drying time decreased
considerably with increase in hot air temperature. Out of the eight
models fitted, the Modified Henderson and Pabis model gave the best
fit to the experimental moisture ratio data on all the varieties while
Newton, Wang and Singh models gave the least. The lower activation
energy (0.27 - 6.54 kJ/mol) obtained indicates that drying of sweet
potato slices requires less energy and is hence a cost and energy
saving method.
Abstract: The postharvest quality management of tomatoes is
important to limit the amount of losses that occur due to deterioration
between harvest and consumption. This study was undertaken to
investigate the effects of pre- and postharvest integrated agrotechnologies,
involving greenhouse microclimate and postharvest
storage conditions, on the postharvest quality attributes of four
tomato cultivars. Tomato fruit firmness, colour (hue angle (h°) and
L* value), pH and total soluble solids for the cultivars Bona,
Star 9037, Star 9009 and Zeal, grown in a fan-pad evaporativelycooled
and an open-ended naturally-ventilated tunnel, were harvested
at the mature-green stage. The tomatoes were stored for 28 days
under cold storage conditions, with a temperature of 13°C and RH of
85%, and under ambient air conditions, with a temperature of 23±
2°C and RH of 52± 4%. This study has provided information on the
effect of integrated pre-harvest and postharvest agro-technologies,
involving greenhouse microclimate and postharvest storage
environment on the postharvest quality attributes of four of the
tomato cultivars in South Africa. NVT-grown tomatoes retained
better textural qualities, but ripened faster by changing from green to
red faster, although these were reduced under cold storage conditions.
FPVT-grown tomatoes had lower firmness, but ripened slowly with
higher colour attributes. With cold storage conditions, the firmness of
FPVT-grown tomatoes was maintained. Cultivar Bona firmness and
colour qualities depreciated the fastest, but it had higher TSS content
and lower pH values. Star 9009 and Star 9037 presented better
quality, by retaining higher firmness and ripening slowly, but they
had the lowest TSS contents and high pH values, especially
Star 9037. Cold storage improved the firmness of tomato cultivars
with poor textural quality and faster colour changes.
Abstract: This paper present the experimental work of double
unit tunnel form building (TFB) subjected to in-plane lateral cyclic
loading. A one third scale of 3-storey double unit of TFB is tested
until its strength degradation. Then, the TFB is repaired and
retrofitted using additional shear wall, steel angle and CFRP sheet.
The crack patterns, lateral strength, stiffness, ductility and equivalent
viscous damping (EVD) were analyzed and compared before and
after repair and retrofit. The result indicates that the lateral strength
increases by 22% in pushing and 27% in pulling direction. Moreover,
the stiffness and ductility obtained before and after retrofit increase
tremendously by 87.87% and 39.66%, respectively. Meanwhile, the
energy absorption measured by equivalent viscous damping obtained
after retrofit increase by 12.34% in pulling direction. It can be
concluded that the proposed retrofit method is capable to increase the
lateral strength capacity, stiffness and energy absorption of double
unit TFB.
Abstract: In structures, stress concentration is a factor of fatigue
fracture. Basically, the stress concentration is a phenomenon that
should be avoided. However, it is difficult to avoid the stress
concentration. Therefore, relaxation of the stress concentration is
important. The stress concentration arises from notches and circular
holes. There is a relaxation method that a composite patch covers a
notch and a circular hole. This relaxation method is used to repair
aerial wings, but it is not systematized. Composites are more
expensive than single materials. Accordingly, we propose the
relaxation method that a single material patch covers a notch and a
circular hole, and aim to systematize this relaxation method.
We performed FEA (Finite Element Analysis) about an object by
using a three-dimensional FEA model. The object was that a patch
adheres to a plate with a circular hole. And, a uniaxial tensile load acts
on the patched plate with a circular hole. In the three-dimensional FEA
model, it is not easy to model the adhesion layer. Basically, the yield
stress of the adhesive is smaller than that of adherents. Accordingly,
the adhesion layer gets to plastic deformation earlier than the adherents
under the yield load of adherents. Therefore, we propose the
three-dimensional FEA model which is applied a nonlinear elastic
region to the adhesion layer. The nonlinear elastic region was
calculated by a bilinear approximation. We compared the analysis
results with the tensile test results to confirm whether the analysis
model has usefulness. As a result, the analysis results agreed with the
tensile test results. And, we confirmed that the analysis model has
usefulness.
As a result that the three-dimensional FEA model was used to the
analysis, it was confirmed that an out-of-plane deformation occurred
to the patched plate with a circular hole. The out-of-plane deformation
causes stress increase of the patched plate with a circular hole.
Therefore, we investigated that the out-of-plane deformation affects
relaxation of the stress concentration in the plate with a circular hole
on this relaxation method. As a result, it was confirmed that the
out-of-plane deformation inhibits relaxation of the stress concentration
on the plate with a circular hole.
Abstract: In this paper, the effect of admixtures on the tensional
strength of concrete in Urmia-lake water have been investigated. We
made different types of concretes with the ratio of w/c and replaced
different percentages of micro-silica, air-entraining, super plasticizer,
corrosion-inhibiting, and caulk with two types of cement I and II as
well as investigating in both ordinary water and Urmia-lake water.
The tensional strength was investigated on these samples.