Abstract: This study investigates the effects of the lead angle
and chip thickness variation on surface roughness during the
machining of compacted graphite iron using ceramic cutting tools
under dry cutting conditions. Analytical models were developed for
predicting the surface roughness values of the specimens after the
face milling process. Experimental data was collected and imported
to the artificial neural network model. A multilayer perceptron model
was used with the back propagation algorithm employing the input
parameters of lead angle, cutting speed and feed rate in connection
with chip thickness. Furthermore, analysis of variance was employed
to determine the effects of the cutting parameters on surface
roughness. Artificial neural network and regression analysis were
used to predict surface roughness. The values thus predicted were
compared with the collected experimental data, and the
corresponding percentage error was computed. Analysis results
revealed that the lead angle is the dominant factor affecting surface
roughness. Experimental results indicated an improvement in the
surface roughness value with decreasing lead angle value from 88° to
45°.
Abstract: Based on Business and Consumer Survey (BCS) data,
the European Commission (EC) regularly publishes the monthly
Economic Sentiment Indicator (ESI) for each EU member state. ESI
is conceptualized as a leading indicator, aimed ad tracking the overall
economic activity. In calculating ESI, the EC employs arbitrarily
chosen weights on 15 BCS response balances. This paper raises the
predictive quality of ESI by applying nonlinear programming to find
such weights that maximize the correlation coefficient of ESI and
year-on-year GDP growth. The obtained results show that the highest
weights are assigned to the response balances of industrial sector
questions, followed by questions from the retail trade sector. This
comes as no surprise since the existing literature shows that the
industrial production is a plausible proxy for the overall Croatian
economic activity and since Croatian GDP is largely influenced by
the aggregate personal consumption.
Abstract: Aging infrastructures became a serious social problem.
This brought out the increased need for the legislation of a new strict
guideline for infrastructure management. Although existing guidelines
provided basics of how to evaluate and manage the condition of
infrastructures, they needed improvements for their evaluation
procedures. Most guidelines mainly focused on the structural
condition of infrastructures and did not properly reflect service aspects
of infrastructures such as performance, public demand, capacity, etc.,
which were significantly valuable to public. Regardless of the
importance, these factors were often neglected in infrastructure
evaluations, because they were quite subjective and difficult to
quantify in rational manner. Thus, this study proposed a framework to
properly identify and evaluate the service indicators. This study
showed that service indicators could be grouped into two categories
and properly evaluated using AHP and Fuzzy. Overall, proposed
framework is expected to assist governmental agency in establishing
effective investment strategies for infrastructure improvements.
Abstract: Food poisoning and infection by bacteria are of public
health significance to both developing and developed countries.
Samples of ogi (akamu) prepared from white and yellow variety of
maize sold in Uturu and Okigwe were analyzed together with the
laboratory prepared ogi for bacterial quality using the standard
microbiological methods. The analyses showed that both white and
yellow variety had total bacterial counts (cfu/g) of 4.0 ×107 and 3.9 x
107 for the laboratory prepared ogi while the commercial ogi had 5.2
x 107 and 4.9 x107, 4.9 x107 and 4.5 x107, 5.4 x107 and 5.0 x107 for
Eke-Okigwe, Up-gate and Nkwo-Achara market respectively. The
Staphylococcal counts ranged from 2.0 x 102 to 5.0 x102 and 1.0 x
102 to 4.0 x102 for the white and yellow variety from the different
markets while Staphylococcal growth was not recorded on the
laboratory prepared ogi. The laboratory prepared ogi had no Coliform
growth while the commercially prepared ogi had counts of 0.5 x103
to 1.6 x 103 for white variety and 0.3 x 103 to 1.1 x103 for yellow
variety respectively. The Lactic acid bacterial count of 3.5x106 and
3.0x106 was recorded for the laboratory ogi while the commercially
prepared ogi ranged from 3.2x106 to 4.2x106 (white variety) and 3.0
x106 to 3.9 x106 (yellow). The presence of bacteria isolates from the
commercial and laboratory fermented ogi showed that Lactobacillus
sp, Leuconostoc sp and Citrobacter sp were present in all the
samples, Micrococcus sp and Klebsiella sp were isolated from Eke-
Okigwe and ABSU-up-gate markets varieties respectively, E. coli
and Staphylococcus sp were present in Eke-Okigwe and Nkwo-
Achara markets while Salmonella sp were isolated from the three
markets. Hence, there are chances of contracting food borne diseases
from commercially prepared ogi. Therefore, there is the need for
sanitary measures in the production of fermented cereals so as to
minimize the rate of food borne pathogens during processing and
storage.
Abstract: Waste Load Allocation (WLA) strategies usually
intend to find economic policies for water resource management.
Water quality trading (WQT) is an approach that uses discharge
permit market to reduce total environmental protection costs. This
primarily requires assigning discharge limits known as total
maximum daily loads (TMDLs). These are determined by monitoring
organizations with respect to the receiving water quality and
remediation capabilities. The purpose of this study is to compare two
approaches of TMDL assignment for WQT policy in small catchment
area of Haraz River, in north of Iran. At first, TMDLs are assigned
uniformly for the whole point sources to keep the concentrations of
BOD and dissolved oxygen (DO) at the standard level at checkpoint
(terminus point). This was simply simulated and controlled by
Qual2kw software. In the second scenario, TMDLs are assigned
using multi objective particle swarm optimization (MOPSO) method
in which the environmental violation at river basin and total treatment
costs are minimized simultaneously. In both scenarios, the equity
index and the WLA based on trading discharge permits (TDP) are
calculated. The comparative results showed that using economically
optimized TMDLs (2nd scenario) has slightly more cost savings rather
than uniform TMDL approach (1st scenario). The former annually
costs about 1 M$ while the latter is 1.15 M$. WQT can decrease
these annual costs to 0.9 and 1.1 M$, respectively. In other word,
these approaches may save 35 and 45% economically in comparison
with command and control policy. It means that using multi objective
decision support systems (DSS) may find more economical WLA,
however its outcome is not necessarily significant in comparison with
uniform TMDLs. This may be due to the similar impact factors of
dischargers in small catchments. Conversely, using uniform TMDLs
for WQT brings more equity that makes stakeholders not feel that
much envious of difference between TMDL and WQT allocation. In
addition, for this case, determination of TMDLs uniformly would be
much easier for monitoring. Consequently, uniform TMDL for TDP
market is recommended as a sustainable approach. However,
economical TMDLs can be used for larger watersheds.
Abstract: This work studies the effect of chemical composition
on the activity and selectivity of γ–alumina supported CuO/
MnO2/Cr2O3 catalysts toward deep oxidation of CO, dimethyl ether
(DME) and methanol. The catalysts were prepared by impregnation
of the support with an aqueous solution of copper nitrate, manganese
nitrate and CrO3 under different conditions. Thermal, XRD and TPR
analysis were performed. The catalytic measurements of single
compounds oxidation were carried out on continuous flow equipment
with a four-channel isothermal stainless steel reactor. Flow-line
equipment with an adiabatic reactor for simultaneous oxidation of all
compounds under the conditions that mimic closely the industrial
ones was used. The reactant and product gases were analyzed by
means of on-line gas chromatographs.
On the basis of XRD analysis it can be concluded that the active
component of the mixed Cu-Mn-Cr/γ–alumina catalysts consists of at
least six compounds – CuO, Cr2O3, MnO2, Cu1.5Mn1.5O4,
Cu1.5Cr1.5O4 and CuCr2O4, depending on the Cu/Mn/Cr molar ratio.
Chemical composition strongly influences catalytic properties, this
influence being quite variable with regards to the different processes.
The rate of CO oxidation rapidly decrease with increasing of
chromium content in the active component while for the DME was
observed the reverse trend. It was concluded that the best
compromise are the catalysts with Cu/(Mn + Cr) molar ratio 1:5 and
Mn/Cr molar ratio from 1:3 to 1:4.
Abstract: Construction projects are information intensive in
nature and involve many activities that are related to each other.
Wireless technologies can be used to improve the accuracy and
timeliness of data collected from construction sites and shares it with
appropriate parties. Nonetheless, the construction industry tends to be
conservative and shows hesitation to adopt new technologies. A main
concern for owners, contractors or any person in charge on a job site
is the cost of the technology in question. Wireless technologies are
not cheap. There are a lot of expenses to be taken into consideration,
and a study should be completed to make sure that the importance
and savings resulting from the usage of this technology is worth the
expenses. This research attempts to assess the effectiveness of using
the appropriate wireless technologies based on criteria such as
performance, reliability, and risk. The assessment is based on a utility
function model that breaks down the selection issue into alternatives
attribute. Then the attributes are assigned weights and single
attributes are measured. Finally, single attribute are combined to
develop one single aggregate utility index for each alternative.
Abstract: In this work new macroporous Ni electrodes modified
with Au nanoparticles for hydrogen production have been developed.
The supporting macroporous Ni electrodes have been obtained by
means of the electrodeposition at high current densities. Then, the Au
nanoparticles were synthesized and added to the electrode surface.
The electrocatalytic behaviour of the developed electrocatalysts was
studied by means of pseudo-steady-state polarization curves,
electrochemical impedance spectroscopy (EIS) and hydrogen
discharge curves. The size of the Au synthetized nanoparticles shows
a monomodal distribution, with a very sharp band between 10 and 50
nm. The characteristic parameters d10, d50 and d90 were 14, 20 and
31 nm respectively. From Tafel polarization data has been concluded
that the Au nanoparticles improve the catalytic activity of the
developed electrodes towards the HER respect to the macroporous Ni
electrodes. EIS permits to obtain the electrochemically active area by
means of the roughness factor value. All the developed electrodes
show roughness factor values in the same order of magnitude. From
the activation energy results it can be concluded that the Au
nanoparticles improve the intrinsic catalytic activity of the
macroporous Ni electrodes.
Abstract: Market is an important factor for start-ups to look into
during decision-making in product development and related areas.
Emerging country markets are more uncertain in terms of information
availability and institutional supports. The literature review of market
uncertainty reveals the need for identifying factors representing the
market uncertainty. This paper identifies factors for market
uncertainty using Exploratory Factor Analysis (EFA) and confirmed
the number of factor retention using an alternative factor retention
criterion ‘Parallel Analysis’. 500 entrepreneurs, engaged in start-ups
from all over India participated in the study. This paper concludes
with the factor structure of ‘market uncertainty’ having dimensions of
uncertainty in industry orientation, uncertainty in customer
orientation and uncertainty in marketing orientation.
Abstract: Evapotranspiration is one of the most important
components of the hydrological cycle. Evapotranspiration (ETo) is an
important variable in water and energy balances on the earth’s
surface, and knowledge of the distribution of ET is a key factor in
hydrology, climatology, agronomy and ecology studies. Many
researchers have a valid relationship, which is a function of climate
factors, to estimate the potential evapotranspiration presented to the
plant water stress or water loss, prevent. The FAO-Penman method
(PM) had been recommended as a standard method. This method
requires many data and these data are not available in every area of
world. So, other methods should be evaluated for these conditions.
When sufficient or reliable data to solve the PM equation are not
available then Hargreaves equation can be used. The Hargreaves
equation (HG) requires only daily mean, maximum and minimum air
temperature extraterrestrial radiation .In this study, Hargreaves
method (HG) were evaluated in 12 stations in the North West region
of Iran. Results of HG and M.HG methods were compared with
results of PM method. Statistical analysis of this comparison showed
that calibration process has had significant effect on efficiency of
Hargreaves method.
Abstract: In recent years, multi-antenna techniques are being considered as a potential solution to increase the flow of future wireless communication systems. The objective of this article is to study the emission and reception system MIMO (Multiple Input Multiple Output), and present the different reception decoding techniques. First we will present the least complex technical, linear receivers such as the zero forcing equalizer (ZF) and minimum mean squared error (MMSE). Then a nonlinear technique called ordered successive cancellation of interferences (OSIC) and the optimal detector based on the maximum likelihood criterion (ML), finally, we simulate the associated decoding algorithms for MIMO system such as ZF, MMSE, OSIC and ML, thus a comparison of performance of these algorithms in MIMO context.
Abstract: This paper presents a new automatic vehicle detection
method from very high resolution aerial images to measure traffic
density. The proposed method starts by extracting road regions from
image using road vector data. Then, the road image is divided into
equal sections considering resolution of the images. Gradient vectors
of the road image are computed from edge map of the corresponding
image. Gradient vectors on the each boundary of the sections are
divided where the gradient vectors significantly change their
directions. Finally, number of vehicles in each section is carried out
by calculating the standard deviation of the gradient vectors in each
group and accepting the group as vehicle that has standard deviation
above predefined threshold value. The proposed method was tested in
four very high resolution aerial images acquired from Istanbul,
Turkey which illustrate roads and vehicles with diverse
characteristics. The results show the reliability of the proposed
method in detecting vehicles by producing 86% overall F1 accuracy
value.
Abstract: This study, for its research subjects, uses patients who
had undergone total knee replacement surgery from the database of the
National Health Insurance Administration. Through the review of
literatures and the interviews with physicians, important factors are
selected after careful screening. Then using Cross Entropy Method,
Genetic Algorithm Logistic Regression, and Particle Swarm
Optimization, the weight of each factor is calculated and obtained. In
the meantime, Excel VBA and Case Based Reasoning are combined
and adopted to evaluate the system. Results show no significant
difference found through Genetic Algorithm Logistic Regression and
Particle Swarm Optimization with over 97% accuracy in both
methods. Both ROC areas are above 0.87. This study can provide
critical reference to medical personnel as clinical assessment to
effectively enhance medical care quality and efficiency, prevent
unnecessary waste, and provide practical advantages to resource
allocation to medical institutes.
Abstract: This article aims to analyze the static stability and
pseudostatic slope by using different methods such as: Bishop
method, Junbu, Ordinary, Morgenstern-price and GLE. The two
dimensional modeling of slope stability under various loading as: the
earthquake effect, the water level and road mobile charges. The
results show that the slope is stable in the static case without water,
but in other cases, the slope lost its stability and give unstable. The
calculation of safety factor is to evaluate the stability of the slope
using the limit equilibrium method despite the difference between the
results obtained by these methods that do not rely on the same
assumptions. In the end, the results of this study illuminate well the
influence of the action of water, moving loads and the earthquake on
the stability of the slope.
Abstract: In recent years a new method of combination
treatment for cancer has been developed and studied that has led to
significant advancements in the field of cancer therapy. Hyperthermia
is a traditional therapy that, along with a creation of a medically
approved level of heat with the help of an alternating magnetic AC
current, results in the destruction of cancer cells by heat. This paper
gives details regarding the production of the spherical nanocomposite
PVA/γ-Fe2O3 in order to be used for medical purposes such as tumor
treatment by hyperthermia. To reach a suitable and evenly distributed
temperature, the nanocomposite with core-shell morphology and
spherical form within a 100 to 200 nanometer size was created using
phase separation emulsion, in which the magnetic nano-particles γ-
Fe2O3 with an average particle size of 20 nano-meters and with
different percentages of 0.2, 0.4, 0.5 and 0.6 were covered by
polyvinyl alcohol. The main concern in hyperthermia and heat
treatment is achieving desirable specific absorption rate (SAR) and
one of the most critical factors in SAR is particle size. In this project
all attempts has been done to reach minimal size and consequently
maximum SAR. The morphological analysis of the spherical
structure of the nanocomposite PVA/γ-Fe2O3 was achieved by SEM
analyses and the study of the chemical bonds created was made
possible by FTIR analysis. To investigate the manner of magnetic
nanocomposite particle size distribution a DLS experiment was
conducted. Moreover, to determine the magnetic behavior of the γ-
Fe2O3 particle and the nanocomposite PVA/γ-Fe2O3 in different
concentrations a VSM test was conducted. To sum up, creating
magnetic nanocomposites with a spherical morphology that would be
employed for drug loading opens doors to new approaches in
developing nanocomposites that provide efficient heat and a
controlled release of drug simultaneously inside the magnetic field,
which are among their positive characteristics that could significantly
improve the recovery process in patients.
Abstract: This paper presents an experimental study on
structural performance of an innovative noise barrier consisting of
poly-block, light polyurethane foam (LPF) and polyurea. This wall
system (flexi-wall) is intended to be employed as a vertical extension
to existing sound barriers in an accelerated construction method. To
aid in the wall design, several mechanical tests were conducted on
LPF specimens and two full-scale walls were then fabricated
employing the same LPF material. The full-scale walls were
subjected to lateral loading in order to establish their lateral
resistance. A cyclic fatigue test was also performed on a full-scale
flexi-wall in order to evaluate the performance of the wall under a
repetitive loading condition. The result of the experiments indicated
the suitability of flexi-wall in accelerated construction and confirmed
that the structural performance of the wall system under lateral
loading is satisfactory for the sound barrier application. The
experimental results were discussed and a preliminary design
procedure for application of flexi-wall in sound barrier applications
was also developed.
Abstract: In this paper, we investigated the athermal pressure
behavior of the structural and elastic properties of scheelite BaWO4
phase up to 7 GPa using the ab initio pseudo-potential method. The
calculated lattice parameters pressure relation have been compared
with the experimental values and found to be in good agreement with
these results. Moreover, we present for the first time the investigation
of the elastic properties of this compound using the density functional
perturbation theory (DFPT). It is shown that this phase is
mechanically stable up to 7 GPa after analyzing the calculated elastic
constants. Other relevant quantities such as bulk modulus, pressure
derivative of bulk modulus, shear modulus; Young’s modulus,
Poisson’s ratio, anisotropy factors, Debye temperature and sound
velocity have been calculated. The obtained results, which are
reported for the first time to the best of the author’s knowledge, can
facilitate assessment of possible applications of the title material.
Abstract: In addition to environmental parameters like rain,
temperature diseases on crop is a major factor which affects
production quality & quantity of crop yield. Hence disease
management is a key issue in agriculture. For the management of
disease, it needs to be detected at early stage. So, treat it properly &
control spread of the disease. Now a day, it is possible to use the
images of diseased leaf to detect the type of disease by using image
processing techniques. This can be achieved by extracting features
from the images which can be further used with classification
algorithms or content based image retrieval systems. In this paper,
color image is used to extract the features such as mean and standard
deviation after the process of region cropping. The selected features
are taken from the cropped image with different image size samples.
Then, the extracted features are taken in to the account for
classification using Fuzzy Inference System (FIS).
Abstract: Riveting process is one of the important ways to keep
fastening the lap joints in aircraft structures. Failure of aircraft lap
joints directly depends on the stress field in the joint. An important
application of riveting process is in the construction of aircraft
fuselage structures. In this paper, a 3D finite element method is
carried out in order to optimize residual stress field in a riveted lap
joint and also to estimate its fatigue life. In continue, a number of
experiments are designed and analyzed using design of experiments
(DOE). Then, Taguchi method is used to select an optimized case
between different levels of each factor. Besides that, the factor which
affects the most on residual stress field is investigated. Such
optimized case provides the maximum residual stress field. Fatigue
life of the optimized joint is estimated by Paris-Erdogan law. Stress
intensity factors (SIFs) are calculated using both finite element
analysis and experimental formula. In addition, the effect of residual
stress field, geometry and secondary bending are considered in SIF
calculation. A good agreement is found between results of such
methods. Comparison between optimized fatigue life and fatigue life
of other joints has shown an improvement in the joint’s life.
Abstract: We report herein the development and preliminary mechanical characterization of fully-dense multi-wall carbon nanotube (MWCNT)-reinforced ceramics and glasses based on a completely new methodology termed High Shear Compaction (HSC). The tubes are introduced and bound to the matrix grains by aid of polymeric binders to form flexible green bodies which are sintered and densified by spark plasma sintering to unprecedentedly high densities of 100% of the pure-matrix value. The strategy was validated across a PyrexTM glass / MWCNT composite while no identifiable factors limit application to other types of matrices. Nondestructive evaluation, based on ultrasonics, of the dynamic mechanical properties of the materials including elastic, shear and bulk modulus as well as Poisson’s ratio showed optimum property improvement at 0.5 %wt tube loading while evidence of nanoscalespecific energy dissipative characteristics acting complementary to nanotube bridging and pull-out indicate a high potential in a wide range of reinforcing and multifunctional applications.