Abstract: Addition of milli or micro sized particles to the heat
transfer fluid is one of the many techniques employed for improving
heat transfer rate. Though this looks simple, this method has
practical problems such as high pressure loss, clogging and erosion
of the material of construction. These problems can be overcome by
using nanofluids, which is a dispersion of nanosized particles in a
base fluid. Nanoparticles increase the thermal conductivity of the
base fluid manifold which in turn increases the heat transfer rate.
Nanoparticles also increase the viscosity of the basefluid resulting in
higher pressure drop for the nanofluid compared to the base fluid. So
it is imperative that the Reynolds number (Re) and the volume
fraction have to be optimum for better thermal hydraulic
effectiveness. In this work, the heat transfer enhancement using
aluminium oxide nanofluid using low and high volume fraction
nanofluids in turbulent pipe flow with constant wall temperature has
been studied by computational fluid dynamic modeling of the
nanofluid flow adopting the single phase approach. Nanofluid, up till
a volume fraction of 1% is found to be an effective heat transfer
enhancement technique. The Nusselt number (Nu) and friction factor
predictions for the low volume fractions (i.e. 0.02%, 0.1 and 0.5%)
agree very well with the experimental values of Sundar and Sharma
(2010). While, predictions for the high volume fraction nanofluids
(i.e. 1%, 4% and 6%) are found to have reasonable agreement with
both experimental and numerical results available in the literature.
So the computationally inexpensive single phase approach can be
used for heat transfer and pressure drop prediction of new nanofluids.
Abstract: Dynamic Causal Modeling (DCM) functional
Magnetic Resonance Imaging (fMRI) is a promising technique to
study the connectivity among brain regions and effects of stimuli
through modeling neuronal interactions from time-series
neuroimaging. The aim of this study is to study characteristics of a
mirror neuron system (MNS) in elderly group (age: 60-70 years old).
Twenty volunteers were MRI scanned with visual stimuli to study a
functional brain network. DCM was employed to determine the
mechanism of mirror neuron effects. The results revealed major
activated areas including precentral gyrus, inferior parietal lobule,
inferior occipital gyrus, and supplementary motor area. When visual
stimuli were presented, the feed-forward connectivity from visual
area to conjunction area was increased and forwarded to motor area.
Moreover, the connectivity from the conjunction areas to premotor
area was also increased. Such findings can be useful for future
diagnostic process for elderly with diseases such as Parkinson-s and
Alzheimer-s.
Abstract: The utilize of renewable energy sources becomes
more crucial and fascinatingly, wider application of renewable
energy devices at domestic, commercial and industrial levels is not
only affect to stronger awareness but also significantly installed
capacities. Moreover, biomass principally is in form of woods and
converts to be energy for using by humans for a long time.
Gasification is a process of conversion of solid carbonaceous fuel
into combustible gas by partial combustion. Many gasified models
have various operating conditions because the parameters kept in
each model are differentiated. This study applied the experimental
data including three inputs variables including biomass consumption;
temperature at combustion zone and ash discharge rate and gas flow
rate as only one output variable. In this paper, response surface
methods were applied for identification of the gasified system
equation suitable for experimental data. The result showed that linear
model gave superlative results.
Abstract: Fischer-Tropsch synthesis is one of the most
important catalytic reactions that convert the synthetic gas to light
and heavy hydrocarbons. One of the main issues is selecting the type
of reactor. The slurry bubble reactor is suitable choice for Fischer-
Tropsch synthesis because of its good qualification to transfer heat
and mass, high durability of catalyst, low cost maintenance and
repair. The more common catalysts for Fischer-Tropsch synthesis are
Iron-based and Cobalt-based catalysts, the advantage of these
catalysts on each other depends on which type of hydrocarbons we
desire to produce. In this study, Fischer-Tropsch synthesis is modeled
with Iron and Cobalt catalysts in a slurry bubble reactor considering
mass and momentum balance and the hydrodynamic relations effect
on the reactor behavior. Profiles of reactant conversion and reactant
concentration in gas and liquid phases were determined as the
functions of residence time in the reactor. The effects of temperature,
pressure, liquid velocity, reactor diameter, catalyst diameter, gasliquid
and liquid-solid mass transfer coefficients and kinetic
coefficients on the reactant conversion have been studied. With 5%
increase of liquid velocity (with Iron catalyst), H2 conversions
increase about 6% and CO conversion increase about 4%, With 8%
increase of liquid velocity (with Cobalt catalyst), H2 conversions
increase about 26% and CO conversion increase about 4%. With
20% increase of gas-liquid mass transfer coefficient (with Iron
catalyst), H2 conversions increase about 12% and CO conversion
increase about 10% and with Cobalt catalyst H2 conversions increase
about 10% and CO conversion increase about 6%. Results show that
the process is sensitive to gas-liquid mass transfer coefficient and
optimum condition operation occurs in maximum possible liquid
velocity. This velocity must be more than minimum fluidization
velocity and less than terminal velocity in such a way that avoid
catalysts particles from leaving the fluidized bed.
Abstract: The study aimed to evaluated the reproductive performance response to short term oestrus synchronization during the transition period. One hundred and sixty-five indigenous multiparous non-lactating goats were subdivided into the following six treatment groups for oestrus synchronization: NT control Group (N= 30), Fe-21d, FGA vaginal sponge for 21days+eCG at 19thd; FPe- 11d, FGA 11d + PGF2α and eCG at 9th d; FPe-10d, FGA 10d+ PGF2α and eCG at 8th d; FPe-9d, FGA 9d +PGF2α and eCG at 7thd; PFe-5d, PGF2α at d0 + FGA 5d + eCG at 5thd. The goats were natural mated (1 male/6 females). Fecundity rates (n. births /n. females treated x 100) were statistically higher (P < 0.05) in short term FPe-9d (157.9%), FPe- 11d (115.4%), FPe-10d (111.1%) and PFe-5d (107.7%) groups compared to the NT control Group (66.7%).
Abstract: Little attention has been paid to information
transmission between the portfolios of large stocks and small stocks in the Korean stock market. This study investigates the return and volatility transmission mechanisms between large and small stocks in
the Korea Exchange (KRX). This study also explores whether bad news in the large stock market leads to a volatility of the small stock
market that is larger than the good news volatility of the large stock market. By employing the Granger causality test, we found
unidirectional return transmissions from the large stocks to medium
and small stocks. This evidence indicates that pat information about
the large stocks has a better ability to predict the returns of the medium and small stocks in the Korean stock market. Moreover, by using the
asymmetric GARCH-BEKK model, we observed the unidirectional relationship of asymmetric volatility transmission from large stocks to
the medium and small stocks. This finding suggests that volatility in
the medium and small stocks following a negative shock in the large
stocks is larger than that following a positive shock in the large stocks.
Abstract: The primary purpose of this article is an attempt to
find the implication of globalization on education. Globalization has
an important role as a process in the economical, political, cultural
and technological dimensions in the life of the contemporary human
being and has been affected by it. Education has its effects in this
procedure and while influencing it through educating global citizens
having universal human features and characteristics, has been
influenced by this phenomenon too. Nowadays, the role of education
is not just to develop in the students the knowledge and skills
necessary for the new kinds of jobs. If education wants to help
students be prepared of the new global society, it has to make them
engaged productive and critical citizens for the global era, so that
they can reflect about their roles as key actors in a dynamic often
uneven, matrix of economic and cultural exchanges. If education
wants to reinforce and raise the national identity, the value system
and the children and teenagers, it should make them ready for living
in the global era of this century. The used method in this research is
documentary and analyzing the documents. Studies in this field show
globalization has influences on the processes of the production,
distribution and consuming of knowledge. The happening of this
event in the information era has not only provide the necessary
opportunities for the exchanges of education worldwide but also has
privileges for the developing countries which enables them to
strengthen educational bases of their society and have an important
step toward their future.
Abstract: This study aims to examine the determinants of
purchase intention in C2C e-commerce. Specifically the role of
instant messaging in the C2C e-commerce contextis investigated. In
addition to instant messaging, we brought in two antecedents of
purchase intention - trust and customer satisfaction - to establish a
theoretical research model. Structural equation modeling using
LISREL was used to analyze the data.We discussed the research
findings and suggested some implications for researchers and
practitioners.
Abstract: This study aimed to present the mechanical
performance evaluation of the dynamic hip screw (DHS) for
trochanteric fracture by means of finite element method. The
analyses were performed based on stainless steel and titanium
implant material definitions at various stages of bone healing and
including implant removal. The assessment of the mechanical
performance used two parameters, von Mises stress to evaluate the
strength of bone and implant and elastic strain to evaluate fracture
stability. The results show several critical aspects of dynamic hip
screw for trochanteric fracture stabilization. In the initial stage of
bone healing process, partial weight bearing should be applied to
avoid the implant failure. In the late stage of bone healing, stainless
steel implant should be removed.
Abstract: In rapidly changing market environment, firms are investing a lot of time and resources into new product development (NPD) projects to make profit and to obtain competitive advantage. However, failure rate of NPD projects is becoming high due to various internal and external risks which hinder successful NPD projects. To reduce the failure rate, it is critical that risks have to be managed effectively and efficiently through good strategy, and treated by optimal responses to minimize risk cost. Four strategies are adopted to handle the risks in this study. The optimal responses are characterized by high reduction of risk costs with high efficiency. This study suggests a framework to decide the optimal responses considering the core risks, risk costs, response efficiency and response costs for successful NPD projects. Both binary particles warm optimization (BPSO) and multi-objective particle swarm optimization (MOPSO) methods are mainly used in the framework. Although several limitations exist in use for real industries, the frame work shows good strength for handling the risks with highly scientific ways through an example.
Abstract: A hybrid Photovoltaic/Thermal (PV/T) solar system integrates photovoltaic and solar thermal technologies into one single solar energy device, with dual generation of electricity and heat energy. The aim of the present study is to evaluate the potential for introduction of the PV/T technology into Northern China. For this purpose, outdoor experiments were conducted on a prototype of a PV/T water-heating system. The annual thermal and electrical performances were investigated under the climatic conditions of Beijing. An economic analysis of the system was then carried out, followed by a sensitivity study. The analysis revealed that the hybrid system is not economically attractive with the current market and energy prices. However, considering the continuous commitment of the Chinese government towards policy development in the renewable energy sector, and technological improvements like the increasing cost-effectiveness of PV cells, PV/Thermal technology may become economically viable in the near future.
Abstract: Turkey has 72 % of total world boron reserves on the
basis of B2O3.Borates that is a refined form of boron minerals have a
wide range of applications. Zinc borates can be used as multifunctional
synergistic additives. The most important properties are
low solubility in water and high dehydration temperature. Zinc
borates dehydrate above 290°C and anhydrous zinc borate has
thermal resistance about 400°C. Zinc borates can be synthesized
using several methods such as hydrothermal and solid-state
processes. In this study, the solid-state method was applied between
500 and 800°C using the starting materials of ZnO and H3BO3 with
1:4 mole ratio. The reaction time was determined as 4 hours after
some preliminary experiments. After the synthesis, the crystal
structure and the morphology of the products were examined by XRay
Diffraction (XRD), Fourier Transform Infrared Spectroscopy
(FT-IR) and Raman Spectrometer. As a result the form of ZnB4O7
was synthesized with the highest crystal score at 800°C.
Abstract: The vast rural landscape in the southern United States
is conspicuously characterized by the hedgerow trees or groves. The
patchwork landscape of fields surrounded by high hedgerows is a
traditional and familiar feature of the American countryside.
Hedgerows are in effect linear strips of trees, groves, or woodlands,
which are often critical habitats for wildlife and important for the
visual quality of the landscape. As landscape interfaces, hedgerows
define the spaces in the landscape, give the landscape life and
meaning, and enrich ecologies and cultural heritages of the American
countryside. Although hedgerows were originally intended as fences
and to mark property and townland boundaries, they are not merely
the natural or man-made additions to the landscape--they have
gradually become “naturalized" into the landscape, deeply rooted in
the rural culture, and now formed an important component of the
southern American rural environment. However, due to the ever
expanding real estate industry and high demand for new residential
development, substantial areas of authentic hedgerow landscape in
the southern United States are being urbanized. Using Hudson Farm
as an example, this study illustrated guidelines of how hedgerows can
be integrated into town planning as green infrastructure and
landscape interface to innovate and direct sustainable land use, and
suggest ways in which such vernacular landscapes can be preserved
and integrated into new development without losing their contextual
inspiration.
Abstract: Measurement of the COD of a spent caustic solution involves firstly digestion of a test sample with dichromate solution and secondly measurement of dichromate remained by titration by ferrous ammonium sulfate [FAS] to an end point. In this paper we study by a potentiometric end point with Ag/AgCl reference electrode and gold rode electrode. The potentiometric end point is sharp and easily identified especially for the samples with high turbidity and color that other methods such as colorimetric in this type of sample do not result in high precision. Because interim of titration responds quickly to potential changes within the [Cr+6/Cr+3& Fe+2/Fe+3] solution producing stable readings that is lead to accurate COD measurement. Finally results are compared with data determined using colorimetric method for standard samples. It is shown that the potentiometric end point titration with gold rode electrode can be used with equal or better facility
Abstract: Artifact free photoplethysmographic (PPG) signals are
necessary for non-invasive estimation of oxygen saturation (SpO2) in
arterial blood. Movement of a patient corrupts the PPGs with motion
artifacts, resulting in large errors in the computation of Sp02. This
paper presents a study on using Kalman Filter in an innovative way
by modeling both the Artillery Blood Pressure (ABP) and the
unwanted signal, additive motion artifact, to reduce motion artifacts
from corrupted PPG signals. Simulation results show acceptable
performance regarding LMS and variable step LMS, thus
establishing the efficacy of the proposed method.
Abstract: The sustainability of a place depends on a series of factors which contribute to the quality of life, sense of place and recognition of identity. An activity like walking, which in itself is obviously ''sustainable'', can become non sustainable if the context in which it is carried out does not meet the conditions for an adequate quality of life. This work is aimed at proposing the analytical method of Place Maker to identify the elements that do not feature in traditional mapping and which constitute the contemporary identity of the places, and the relative complex map to represent those elements and support sustainable urban identity design. The method's potential for areas with a predominantly pedestrian vocation is illustrated by means of the case study of the Ramblas in Barcelona.
Abstract: Cenozoic basalts found in Jiangsu province of eastern
China include tholeiites and alkali basalts. The present paper analyzed
the major, trace elements, rare earth elements of these Cenozoic
basalts and combined with Sr-Nd isotopic compositions proposed by
Chen et al. (1990)[1] in the literatures to discuss the petrogenesis of
these basalts and the geochemical characteristics of the source mantle.
Based on major, trace elements and fractional crystallization model
established by Brooks and Nielsen (1982)[2] we suggest that the
basaltic magma has experienced olivine + clinopyroxene fractionation
during its evolution. The chemical compositions of basaltic rocks from
Jiangsu province indicate that these basalts may belong to the same
magmatic system. Spidergrams reveal that Cenozoic basalts from
Jiangsu province have geochemical characteristics similar to those of
ocean island basalts(OIB). The slight positive Nb and Ti anomalies
found in basaltic rocks of this study suggest the presence of Ti-bearing
minerals in the mantle source and these Ti-bearing minerals had
contributed to basaltic magma during partial melting, indicating a
metasomatic event might have occurred before the partial melting.
Based on the Sr vs. Nd isotopic ratio plots, we suggest that Jiangsu
basalts may be derived from partial melting of mantle source which
may represent two-end members mixing of DMM and EM-I. Some
Jiangsu basaltic magma may be derived from partial melting of EM-I
heated by the upwelling asthenospheric mantle or asthenospheric
diapirism.
Abstract: The purpose of this paper is to present two different
approaches of financial distress pre-warning models appropriate for
risk supervisors, investors and policy makers. We examine a sample
of the financial institutions and electronic companies of Taiwan
Security Exchange (TSE) market from 2002 through 2008. We
present a binary logistic regression with paned data analysis. With
the pooled binary logistic regression we build a model including
more variables in the regression than with random effects, while the
in-sample and out-sample forecasting performance is higher in
random effects estimation than in pooled regression. On the other
hand we estimate an Adaptive Neuro-Fuzzy Inference System
(ANFIS) with Gaussian and Generalized Bell (Gbell) functions and
we find that ANFIS outperforms significant Logit regressions in both
in-sample and out-of-sample periods, indicating that ANFIS is a
more appropriate tool for financial risk managers and for the
economic policy makers in central banks and national statistical
services.
Abstract: Carbon nanotubes (CNTs) with their high mechanical,
electrical, thermal and chemical properties are regarded as promising
materials for many different potential applications. Having unique
properties they can be used in a wide range of fields such as
electronic devices, electrodes, drug delivery systems, hydrogen
storage, textile etc. Catalytic chemical vapor deposition (CCVD) is a
common method for CNT production especially for mass production.
Catalysts impregnated on a suitable substrate are important for
production with chemical vapor deposition (CVD) method. Iron
catalyst and MgO substrate is one of most common catalyst-substrate
combination used for CNT. In this study, CNTs were produced by
CCVD of acetylene (C2H2) on magnesium oxide (MgO) powder
substrate impregnated by iron nitrate (Fe(NO3)3•9H2O) solution. The
CNT synthesis conditions were as follows: at synthesis temperatures
of 500 and 800°C multiwall and single wall CNTs were produced
respectively. Iron (Fe) catalysts were prepared by with Fe:MgO ratio
of 1:100, 5:100 and 10:100. The duration of syntheses were 30 and
60 minutes for all temperatures and catalyst percentages. The
synthesized materials were characterized by thermal gravimetric
analysis (TGA), transmission electron microscopy (TEM) and Raman
spectroscopy.
Abstract: This paper aims to (1) analyze the profiles of
transgressors (detected evaders); (2) examine reason(s) that triggered a
tax audit, causes of tax evasion, audit timeframe and tax penalty
charged; and (3) to assess if tax auditors followed the guidelines as
stated in the 'Tax Audit Framework' when conducting tax audits. In
2011, the Inland Revenue Board Malaysia (IRBM) had audited and
finalized 557 company cases. With official permission, data of all the
557 cases were obtained from the IRBM. Of these, a total of 421 cases
with complete information were analyzed. About 58.1% was small and
medium corporations and from the construction industry (32.8%). The
selection for tax audit was based on risk analysis (66.8%), information
from third party (11.1%), and firm with low profitability or fluctuating
profit pattern (7.8%). The three persistent causes of tax evasion by
firms were over claimed expenses (46.8%), fraudulent reporting of
income (38.5%) and overstating purchases (10.5%). These findings
are consistent with past literature. Results showed that tax auditors
took six to 18 months to close audit cases. More than half of tax
evaders were fined 45% on additional tax raised during audit for the
first offence. The study found tax auditors did follow the guidelines in
the 'Tax Audit Framework' in audit selection, settlement and penalty
imposition.