Abstract: Microstructural and electrical properties of
Cu-chromium alloy (Cu-Cr) dispersed with vapor-grown carbon fiber
(VGCF) prepared by powder metallurgy (P/M) process have been
investigated. Cu-0.7 mass% Cr pre-alloyed powder (Cu-Cr) made by
water atomization process was used as raw materials, which contained
solid solute Cr elements in Cu matrix. The alloy powder coated with
un-bundled VGCF by using oil coating process was consolidated at
1223 K in vacuum by spark plasma sintering, and then extruded at
1073 K. The extruded Cu-Cr alloy (monolithic alloy) had 209.3 MPa
YS and 80.4 IACS% conductivity. The extruded Cu-Cr with 0.1
mass% VGCF composites revealed a small decrease of YS compared
to the monolithic Cu-Cr alloy. On the other hand, the composite had a
higher electrical conductivity than that of the monolithic alloy. For
example, Cu-Cr with 0.1 mass% VGCF composite sintered for 5 h
showed 182.7 MPa YS and 89.7 IACS% conductivity. In the case of
Cu-Cr with VGCFs composites, the Cr concentration was observed
around VGCF by SEM-EDS analysis, where Cr23C6 compounds were
detected by TEM observation. The amount of Cr solid solution in the
matrix of the Cu-Cr composites alloy was about 50% compared to the
monolithic Cu-Cr sintered alloy, and resulted in the remarkable
increment of the electrical conductivity.
Abstract: Transportation of long turbine blades from one place
to another is a difficult process. Hence a feasibility study of
modularization of wind turbine blade was taken from structural
standpoint through finite element analysis. Initially, a non-segmented
blade is modeled and its structural behavior is evaluated to serve as
reference. The resonant, static bending and fatigue tests are simulated
in accordance with IEC61400-23 standard for comparison purpose.
The non-segmented test blade is separated at suitable location based
on trade off studies and the segments are joined with an innovative
double strap bonded joint configuration. The adhesive joint is
modeled by adopting cohesive zone modeling approach in ANSYS.
The developed blade model is analyzed for its structural response
through simulation. Performances of both the blades are found to be
similar, which indicates that, efficient segmentation of the long blade
is possible which facilitates easy transportation of the blades and on
site reassembling. The location selected for segmentation and
adopted joint configuration has resulted in an efficient segmented
blade model which proves the methodology adopted for segmentation
was quite effective. The developed segmented blade appears to be the
viable alternative considering its structural response specifically in
fatigue within considered assumptions.
Abstract: Waste load allocation (WLA) policies may use multiobjective
optimization methods to find the most appropriate and
sustainable solutions. These usually intend to simultaneously
minimize two criteria, total abatement costs (TC) and environmental
violations (EV). If other criteria, such as inequity, need for
minimization as well, it requires introducing more binary
optimizations through different scenarios. In order to reduce the
calculation steps, this study presents value index as an innovative
decision making approach. Since the value index contains both the
environmental violation and treatment costs, it can be maximized
simultaneously with the equity index. It implies that the definition of
different scenarios for environmental violations is no longer required.
Furthermore, the solution is not necessarily the point with minimized
total costs or environmental violations. This idea is testified for Haraz
River, in north of Iran. Here, the dissolved oxygen (DO) level of river
is simulated by Streeter-Phelps equation in MATLAB software. The
WLA is determined for fish farms using multi-objective particle
swarm optimization (MOPSO) in two scenarios. At first, the trade-off
curves of TC-EV and TC-Inequity are plotted separately as the
conventional approach. In the second, the Value-Equity curve is
derived. The comparative results show that the solutions are in a
similar range of inequity with lower total costs. This is due to the
freedom of environmental violation attained in value index. As a
result, the conventional approach can well be replaced by the value
index particularly for problems optimizing these objectives. This
reduces the process to achieve the best solutions and may find better
classification for scenario definition. It is also concluded that decision
makers are better to focus on value index and weighting its contents
to find the most sustainable alternatives based on their requirements.
Abstract: In wastewater treatment processes, aeration introduces
air into a liquid. In these systems, air is introduced by different
devices submerged in the wastewater. Smaller bubbles result in more
bubble surface area per unit of volume and higher oxygen transfer
efficiency. Jet pumps are devices that use air bubbles and are widely
used in wastewater treatment processes. The principle of jet pumps is
their ability to transfer energy of one fluid, called primary or motive,
into a secondary fluid or gas. These pumps have no moving parts and
are able to work in remote areas under extreme conditions. The
objective of this work is to study experimentally the characteristics of
the jet pump and the size of air bubbles in the laboratory water tank.
The effect of flow rate ratio on pump performance is investigated in
order to have a better understanding about pump behavior under
various conditions, in order to determine the efficiency of receiving
air bubbles different sizes. The experiments show that we should take
care when increasing the flow rate ratio while seeking to decrease
bubble size in the outlet flow. This study will help improve and
extend the use of the jet pump in many practical applications.
Abstract: Many industrial materials like magnets need to be
tested for the radiation environment expected at linear colliders (LC)
where the accelerator and detectors will be subjected to large
influences of beta, neutron and gamma’s over their life Gamma
irradiation of the permanent sample magnets using a 60Co source was
investigated up to an absorbed dose of 700Mrad shows a negligible
effect on some magnetic properties of Nd-Fe-B. In this work it has
been tried to investigate the change of some important properties of
Barium hexa ferrite. Results showed little decreases of magnetic
properties at doses rang of 0.5 to 2.5 Mrad. But at the gamma
irradiation dose up to 10 Mrad it is showed a few increase of
properties. Also study of gamma irradiation of Nd-Fe-B showed
considerably increase of magnetic properties.
Abstract: Edge is variation of brightness in an image. Edge
detection is useful in many application areas such as finding forests,
rivers from a satellite image, detecting broken bone in a medical
image etc. The paper discusses about finding edge of multiple aerial
images in parallel. The proposed work tested on 38 images 37
colored and one monochrome image. The time taken to process N
images in parallel is equivalent to time taken to process 1 image in
sequential. Message Passing Interface (MPI) and Open Computing
Language (OpenCL) is used to achieve task and pixel level
parallelism respectively.
Abstract: The grain quality of chickpea in Iran is low and
instable, which may be attributed to the evolution of cultivars with a
narrow genetic base making them vulnerable to biotic stresses. Four
chickpea varieties from diverse geographic origins were chosen and
arranged in a randomized complete block design. Mesorhizobium sp.
cicer strain SW7 was added to all the chickpea seeds. Chickpea seeds
were planted on October 9, 2013. Each genotype was sown 5 m in
length, with 35 cm inter-row spacing, in 3 rows. Weeds were
removed manually in all plots. Results showed that Analysis of
variance on the studied traits showed significant differences among
genotypes for N, P, K and Fe contents of chickpea, but there is not a
significant difference among Ca, Zn and Mg continents of chickpea.
The experimental coefficient of variation (CV) varied from 7.3 to
15.8. In general, the CV value lower than 20% is considered to be
good, indicating the accuracy of conducted experiments. The highest
grain N was observed in Hashem and Jam cultivars. The highest grain
P was observed in Jam cultivar. Phosphorus content (mg/100g)
ranged from 142.3 to 302.3 with a mean value of 221.3. The negative
correlation (-0.126) was observed between the N and P of chickpea
cultivars. The highest K and Fe contents were observed in Jam
cultivar.
Abstract: This paper is aimed to the use of different types of
industrial wastes in concrete production. From examined waste
(crushed concrete waste) our tested concrete samples with dimension
150 mm were prepared. In these samples, fractions 4/8 mm and 8/16
mm by recycled concrete aggregate with a range of variation from 0
to 100% were replaced. Experiment samples were tested for
compressive strength after 2, 7, 14 and 28 days of hardening.
From obtained results it is evident that all samples prepared with
washed recycled concrete aggregates met the requirement of standard
for compressive strength of 20 MPa already after 14 days of
hardening. Sample prepared with recycled concrete aggregates (4/8
mm: 100% and 8/16 mm: 60%) reached 101% of compressive
strength value (34.7 MPa) after 28 days of hardening in comparison
with the reference sample (34.4 MPa). The lowest strength after 28
days of hardening (27.42 MPa) was obtained for sample consisting of
recycled concrete in proportion of 40% for 4/8 fraction and 100% for
8/16 fraction of recycled concrete.
Abstract: Structural Equation Modeling (SEM) was used to test
a hypothesized model explaining Malaysian hypermarket customers’
perceptions of brand trust (BT), customer perceived value (CPV) and
perceived service quality (PSQ) on building their brand loyalty
(CBL) and generating positive word-of-mouth communication
(WOM). Self-administered questionnaires were used to collect data
from 374 Malaysian hypermarket customers from Mydin, Tesco,
Aeon Big and Giant in Kuala Lumpur, a metropolitan city of
Malaysia. The data strongly supported the model exhibiting that BT,
CPV and PSQ are prerequisite factors in building customer brand
loyalty, while PSQ has the strongest effect on prediction of customer
brand loyalty compared to other factors. Besides, the present study
suggests the effect of the aforementioned factors via customer brand
loyalty strongly contributes to generate positive word of mouth
communication.
Abstract: Mangosteen (Garcinia mangostana) pericarp is
considered as agricultural waste and not fully utilized in food
products. It is widely reported that mangosteen pericarp contains high
antioxidant properties. The objective of this study is to develop novel
yellow alkaline noodle (YAN) substituted with different levels of
mangosteen pericarp powder (MPP). YAN formulation was
substituted with different levels of MPP (0%, 5%, 10% and 15%).
The effect on nutritional and antioxidant properties was evaluated.
Higher substitution levels of MPP resulted in significant increase
(p
Abstract: Rehabilitation of dam components such as foundations, buttresses, spillways and overtopping protection require a wide range of construction and design methodologies. Geotechnical Engineering considerations play an important role in the design and construction of foundations of new dams. Much investigation is required to assess and evaluate the existing dams. The application of roller compacting concrete (RCC) has been accepted as a new method for constructing new dams or rehabilitating old ones. In the past 40 years there have been so many changes in the usage of RCC and now it is one of most satisfactory solutions of water and hydropower resource throughout the world. The considerations of rehabilitation and construction of dams might differ due to upstream reservoir and its influence on penetrating and dewatering of downstream, operations requirements and plant layout. One of the advantages of RCC is its rapid placement which allows the dam to be operated quickly. Unlike ordinary concrete it is a drier mix, and stiffs enough for compacting by vibratory rollers. This paper evaluates some different aspects of RCC and focuses on its preparation progress.
Abstract: The structures obtained with the use of sandwich
technologies combine low weight with high energy absorbing
capacity and load carrying capacity. Hence, there is a growing and
markedly interest in the use of sandwiches with aluminum foam core
because of very good properties such as flexural rigidity and energy
absorption capability. In the current investigation, the static threepoint
bending tests were carried out on the sandwiches with
aluminum foam core and glass fiber reinforced polymer (GFRP)
skins at different values of support span distances aiming the analyses
of their flexural performance. The influence of the core thickness and
the GFRP skin type was reported in terms of peak load and energy
absorption capacity. For this purpose, the skins with two different
types of fabrics which have same thickness value and the aluminum
foam core with two different thicknesses were bonded with a
commercial polyurethane based flexible adhesive in order to combine
the composite sandwich panels. The main results of the bending tests
are: force-displacement curves, peak force values, absorbed energy,
collapse mechanisms and the effect of the support span length and
core thickness. The results of the experimental study showed that the
sandwich with the skins made of S-Glass Woven fabrics and with the
thicker foam core presented higher mechanical values such as load
carrying and energy absorption capacities. The increment of the
support span distance generated the decrease of the mechanical
values for each type of panels, as expected, because of the inverse
proportion between the force and span length. The most common
failure types of the sandwiches are debonding of the lower skin and
the core shear. The obtained results have particular importance for
applications that require lightweight structures with a high capacity
of energy dissipation, such as the transport industry (automotive,
aerospace, shipbuilding and marine industry), where the problems of
collision and crash have increased in the last years.
Abstract: The present study was carried out to investigate the
effect of alloying elements and thermo-mechanical treatment (TMT)
i.e. hot rolling and forging with different reduction ratios on the
hardness (HV) and impact toughness (J) of heat-treated low alloy
steels. An understanding of the combined effect of TMT and alloying
elements and by measuring hardness, impact toughness, resulting
from different heat treatment following TMT of the low alloy steels,
it is possible to determine which conditions yielded optimum
mechanical properties and high strength to weight ratio.
Experimental Correlations between hot work reduction ratio,
hardness and impact toughness for thermo-mechanically heat treated
low alloy steels are analyzed quantitatively, and both regression and
mathematical hardness and impact toughness models are developed.
Abstract: This paper presents an optimal broadcast algorithm
for the hypercube networks. The main focus of the paper is the
effectiveness of the algorithm in the presence of many node faults.
For the optimal solution, our algorithm builds with spanning tree
connecting the all nodes of the networks, through which messages
are propagated from source node to remaining nodes. At any given
time, maximum n − 1 nodes may fail due to crashing. We show
that the hypercube networks are strongly fault-tolerant. Simulation
results analyze to accomplish algorithm characteristics under many
node faults. We have compared our simulation results between our
proposed method and the Fu’s method. Fu’s approach cannot tolerate
n − 1 faulty nodes in the worst case, but our approach can tolerate
n − 1 faulty nodes.
Abstract: During the post-Civil War era, the city of Nashville,
Tennessee, had the highest mortality rate in the United States. The
elevated death and disease rates among former slaves were
attributable to lack of quality healthcare. To address the paucity of
healthcare services, Meharry Medical College, an institution with the
mission of educating minority professionals and serving the
underserved population, was established in 1876.
Purpose: The social ecological framework and partial least squares
(PLS) path modeling were used to quantify the impact of
socioeconomic status and adverse health outcome on primary care
professionals serving the disadvantaged community. Thus, the study
results could demonstrate the accomplishment of the College’s
mission of training primary care professionals to serve in underserved
areas.
Methods: Various statistical methods were used to analyze alumni
data from 1975 – 2013. K-means cluster analysis was utilized to
identify individual medical and dental graduates in the cluster groups
of the practice communities (Disadvantaged or Non-disadvantaged
Communities). Discriminant analysis was implemented to verify the
classification accuracy of cluster analysis. The independent t-test was
performed to detect the significant mean differences of respective
clustering and criterion variables. Chi-square test was used to test if
the proportions of primary care and non-primary care specialists are
consistent with those of medical and dental graduates practicing in
the designated community clusters. Finally, the PLS path model was
constructed to explore the construct validity of analytic model by
providing the magnitude effects of socioeconomic status and adverse
health outcome on primary care professionals serving the
disadvantaged community.
Results: Approximately 83% (3,192/3,864) of Meharry Medical
College’s medical and dental graduates from 1975 to 2013 were
practicing in disadvantaged communities. Independent t-test confirmed the content validity of the cluster analysis model. Also, the
PLS path modeling demonstrated that alumni served as primary care
professionals in communities with significantly lower socioeconomic
status and higher adverse health outcome (p < .001). The PLS path
modeling exhibited the meaningful interrelation between primary
care professionals practicing communities and surrounding
environments (socioeconomic statues and adverse health outcome),
which yielded model reliability, validity, and applicability.
Conclusion: This study applied social ecological theory and
analytic modeling approaches to assess the attainment of Meharry
Medical College’s mission of training primary care professionals to
serve in underserved areas, particularly in communities with low
socioeconomic status and high rates of adverse health outcomes. In
summary, the majority of medical and dental graduates from Meharry
Medical College provided primary care services to disadvantaged
communities with low socioeconomic status and high adverse health
outcome, which demonstrated that Meharry Medical College has
fulfilled its mission. The high reliability, validity, and applicability of
this model imply that it could be replicated for comparable
universities and colleges elsewhere.
Abstract: The model tests were conducted in the laboratory
without and with Plastic recycled polymer in fly ash steep slopes
overlaying soft foundation soils like fly ash and powai soil in order to
check the stability of steep slope. In this experiment, fly ash is used
as a filling material and Plastic Recycled Polymers of diameter =
3mm and length = 4mm were made from waste plastic product (lower
grade plastic product). The properties of fly ash and Plastic recycled
polymers are determined. From the experiments, load and settlement
have measured. From these data, load –settlement curves have
reported. It has been observed from test results that load carrying
capacity of mixture fly ash with Plastic Recycled Polymers slope is
more than that of fly ash slope. The deformation of Plastic Recycled
Polymers slope is slightly more than that of fly ash slope. A Finite
Element Method (F.E.M.) was also evaluated using PLAXIS 3D
version. The failure pattern, deformations and factor of safety are
reported based on analytical programme. The results from
experimental data and analytical programme are compared and
reported.
Abstract: Breast cancer is considered as a substantial health
concern and practicing mammography screening [MS] is important in
minimizing its related morbidity. So it is essential to have a better
understanding of breast cancer screening behaviors of women and
factors that influence utilization of them. The aim of this study is to
identify the factors that are linked to MS behaviors among the
Egyptian women. A cross-sectional descriptive design was carried
out to provide a snapshot of the factors that are linked to MS
behaviors. A convenience sample of 311 women was utilized and all
eligible participants admitted to the Women Imaging Unit who are 40
years of age or above, coming for mammography assessment, not
pregnant or breast feeding and who accepted to participate in the
study were included. A structured questionnaire was developed by
the researchers and contains three parts; Socio-demographic data;
Motivating factors associated with MS; and association between MS
and model of behavior change. The analyzed data indicated that most
of the participated women (66.6%) belonged to the age group of 40-
49.A high proportion of participants (58.1%) of group having
previous MS influenced by their neighbors to practice MS, whereas
32.7 % in group not having previous MS were influenced by family
members which indicated significant differences (P
Abstract: This paper proposes techniques like MT CMOS,
POWER GATING, DUAL STACK, GALEOR and LECTOR to
reduce the leakage power. A Full Adder has been designed using
these techniques and power dissipation is calculated and is compared
with general CMOS logic of Full Adder.
Simulation results show the validity of the proposed techniques is
effective to save power dissipation and to increase the speed of
operation of the circuits to a large extent.
Abstract: Every year, a considerable amount of money is being
invested on research, mainly in the form of funding allocated to
universities and research institutes. To better distribute the available
funds and to set the most proper R&D investment strategies for the
future, evaluation of the productivity of the funded researchers and
the impact of such funding is crucial. In this paper, using the data on
15 years of journal publications of the NSERC (Natural Sciences and
Engineering research Council of Canada) funded researchers and by
means of bibliometric analysis, the scientific development of the
funded researchers and their scientific collaboration patterns will be
investigated in the period of 1996-2010. According to the results it
seems that there is a positive relation between the average level of
funding and quantity and quality of the scientific output. In addition,
whenever funding allocated to the researchers has increased, the
number of co-authors per paper has also augmented. Hence, the
increase in the level of funding may enable researchers to get
involved in larger projects and/or scientific teams and increase their
scientific output respectively.
Abstract: Fly ash (FA) thanks to the significant presence of SiO2
and Al2O3 as the main components is a potential raw material for
geopolymers production. Mechanical activation is a method for
improving FA reactivity and also the porosity of final mixture; those
parameters can be analysed through sorption properties. They have
direct impact on the durability of fly ash based geopolymer mortars.
In the paper, effect of FA fineness on sorption properties of
geopolymers based on sodium silicate, as well as relationship
between fly ash fineness and apparent density, compressive and
flexural strength of geopolymers are presented. The best results in the
evaluated area reached the sample H1, which contents the highest
portion of particle under 20μm (100% of GFA). The interdependence
of individual tested properties was confirmed for geopolymer
mixtures corresponding to those in the cement based mixtures: higher
is portion of fine particles < 20μm, higher is strength, density and
lower are sorption properties. The compressive strength as well as
sorption parameters of the geopolymer can be reasonably controlled
by grinding process and also ensured by the higher share of fine
particle (to 20μm) in total mass of the material.