Abstract: Incineration of municipal solid waste (MSW) is one of
the key scopes in the global clean energy strategy. A computational
fluid dynamics (CFD) model was established in order to reveal these
features of the combustion process in a fixed porous bed of MSW.
Transporting equations and process rate equations of the waste bed
were modeled and set up to describe the incineration process,
according to the local thermal conditions and waste property
characters. Gas phase turbulence was modeled using k-ε turbulent
model and the particle phase was modeled using the kinetic theory of
granular flow. The heterogeneous reaction rates were determined
using Arrhenius eddy dissipation and the Arrhenius-diffusion
reaction rates. The effects of primary air flow rate and temperature in
the burning process of simulated MSW are investigated
experimentally and numerically. The simulation results in bed are
accordant with experimental data well. The model provides detailed
information on burning processes in the fixed bed, which is otherwise
very difficult to obtain by conventional experimental techniques.
Abstract: In this study, a computational fluid dynamics (CFD)
model has been developed for studying the effect of surface
roughness profile on the EHL problem. The cylinders contact
geometry, meshing and calculation of the conservation of mass and
momentum equations are carried out using the commercial software
packages ICEMCFD and ANSYS Fluent. The user defined functions
(UDFs) for density, viscosity and elastic deformation of the cylinders
as the functions of pressure and temperature are defined for the CFD
model. Three different surface roughness profiles are created and
incorporated into the CFD model. It is found that the developed CFD
model can predict the characteristics of fluid flow and heat transfer in
the EHL problem, including the main parameters such as pressure
distribution, minimal film thickness, viscosity, and density changes.
The results obtained show that the pressure profile at the center of the
contact area directly relates to the roughness amplitude. A rough
surface with kurtosis value of more than 3 has greater influence over
the fluctuated shape of pressure distribution than in other cases.
Abstract: Traditional document representation for classification
follows Bag of Words (BoW) approach to represent the term weights.
The conventional method uses the Vector Space Model (VSM) to
exploit the statistical information of terms in the documents and they
fail to address the semantic information as well as order of the terms
present in the documents. Although, the phrase based approach
follows the order of the terms present in the documents rather than
semantics behind the word. Therefore, a semantic concept based
approach is used in this paper for enhancing the semantics by
incorporating the ontology information. In this paper a novel method
is proposed to forecast the intraday stock market price directional
movement based on the sentiments from Twitter and money control
news articles. The stock market forecasting is a very difficult and
highly complicated task because it is affected by many factors such
as economic conditions, political events and investor’s sentiment etc.
The stock market series are generally dynamic, nonparametric, noisy
and chaotic by nature. The sentiment analysis along with wisdom of
crowds can automatically compute the collective intelligence of
future performance in many areas like stock market, box office sales
and election outcomes. The proposed method utilizes collective
sentiments for stock market to predict the stock price directional
movements. The collective sentiments in the above social media have
powerful prediction on the stock price directional movements as
up/down by using Granger Causality test.
Abstract: Parabolic solar trough systems have seen limited
deployments in cold northern climates as they are more suitable for
electricity production in southern latitudes. A numerical dynamic
model is developed to simulate troughs installed in cold climates and
validated using a parabolic solar trough facility in Winnipeg. The
model is developed in Simulink and will be utilized to simulate a trigeneration
system for heating, cooling and electricity generation in
remote northern communities. The main objective of this simulation
is to obtain operational data of solar troughs in cold climates and use
the model to determine ways to improve the economics and address
cold weather issues.
In this paper the validated Simulink model is applied to simulate a
solar assisted absorption cooling system along with electricity
generation using Organic Rankine Cycle (ORC) and thermal storage.
A control strategy is employed to distribute the heated oil from solar
collectors among the above three systems considering the
temperature requirements. This modelling provides dynamic
performance results using measured meteorological data recorded
every minute at the solar facility location. The purpose of this
modeling approach is to accurately predict system performance at
each time step considering the solar radiation fluctuations due to
passing clouds. Optimization of the controller in cold temperatures is
another goal of the simulation to for example minimize heat losses in
winter when energy demand is high and solar resources are low.
The solar absorption cooling is modeled to use the generated heat
from the solar trough system and provide cooling in summer for a
greenhouse which is located next to the solar field.
The results of the simulation are presented for a summer day in
Winnipeg which includes comparison of performance parameters of
the absorption cooling and ORC systems at different heat transfer
fluid (HTF) temperatures.
Abstract: In this paper, the exergy analysis of vapor absorption
refrigeration system using LiBr-H2O as working fluid is carried out
with the modified Gouy-Stodola approach rather than the classical
Gouy-Stodola equation and effect of varying input parameters is also
studied on the performance of the system. As the modified approach
uses the concept of effective temperature, the mathematical
expressions for effective temperature have been formulated and
calculated for each component of the system. Various constraints and
equations are used to develop program in EES to solve these
equations. The main aim of this analysis is to determine the
performance of the system and the components having major
irreversible loss. Results show that exergy destruction rate is
considerable in absorber and generator followed by evaporator and
condenser. There is an increase in exergy destruction in generator,
absorber and condenser and decrease in the evaporator by the
modified approach as compared to the conventional approach. The
value of exergy determined by the modified Gouy-Stodola equation
deviates maximum i.e. 26% in the generator as compared to the
exergy calculated by the classical Gouy-Stodola method.
Abstract: Essential oils have a significant antimicrobial activity.
These oils can successfully replace the antibiotics. So, the
microorganisms show their inefficiencies resistant for the antibiotics.
For this reason, we study the physicochemical analysis and
antimicrobial activity of the essential oil of Daucus carota. The
extraction is done by steam distillation of water which brought us a
very significant return of 4.65%. The analysis of the essential oil is
performed by GC / MS and has allowed us to identify 32 compounds
in the oil of D. carota flowering tops of Bouira. Three of which are in
the majority are the α-Pinene (22.3%), the carotol (21.7%) and the
limonene (15.8%).
Abstract: Today’s VLSI networks demands for high speed. And
in this work the compact form mathematical model for current mode
signalling in VLSI interconnects is presented.RLC interconnect line
is modelled using characteristic impedance of transmission line and
inductive effect. The on-chip inductance effect is dominant at lower
technology node is emulated into an equivalent resistance. First order
transfer function is designed using finite difference equation, Laplace
transform and by applying the boundary conditions at the source and
load termination. It has been observed that the dominant pole
determines system response and delay in the proposed model. The
novel proposed current mode model shows superior performance as
compared to voltage mode signalling. Analysis shows that current
mode signalling in VLSI interconnects provides 2.8 times better
delay performance than voltage mode. Secondly the damping factor
of a lumped RLC circuit is shown to be a useful figure of merit.
Abstract: Applications of the Hausdorff space and its mappings
into tangent spaces are outlined, including their fractal dimensions
and self-similarities. The paper details this theory set up and further
describes virtualizations and atomization of manufacturing processes.
It demonstrates novel concurrency principles that will guide
manufacturing processes and resources configurations. Moreover,
varying levels of details may be produced by up folding and breaking
down of newly introduced generic models. This choice of layered
generic models for units and systems aspects along specific aspects
allows research work in parallel to other disciplines with the same
focus on all levels of detail. More credit and easier access are granted
to outside disciplines for enriching manufacturing grounds. Specific
mappings and the layers give hints for chances for interdisciplinary
outcomes and may highlight more details for interoperability
standards, as already worked on the international level. The new rules
are described, which require additional properties concerning all
involved entities for defining distributed decision cycles, again on the
base of self-similarity. All properties are further detailed and assigned
to a maturity scale, eventually displaying the smartness maturity of a
total shopfloor or a factory. The paper contributes to the intensive
ongoing discussion in the field of intelligent distributed
manufacturing and promotes solid concepts for implementations of
Cyber Physical Systems and the Internet of Things into
manufacturing industry, like industry 4.0, as discussed in German-speaking
countries.
Abstract: Nanofibers are effective materials which have
frequently been investigated to produce high quality air filters. As an
environmental approach our aim is to achieve nanofibers by melting.
In spun-bond systems extruder, spin-pump, nozzle package and
attenuator are used. Molten polymer which flows from extruder is
made steady by spin-pump. Regular melt passes through nozzle holes
and forms fibers under high pressure. The fibers pulled from nozzle
are shrunk to micron size by an attenuator; after solidification, they
are collected on a conveyor. In this research different designs of
attenuator system have been studied; and also CFD analysis has been
done on these different designs. Afterwards, one of these designs
tested and finally some optimizations have been done to reduce
pressure loss and increase air velocity.
Abstract: Groundwater inflow to the tunnels is one of the most
important problems in tunneling operation. The objective of this
study is the investigation of model dimension effects on tunnel inflow
assessment in discontinuous rock masses using numerical modeling.
In the numerical simulation, the model dimension has an important
role in prediction of water inflow rate. When the model dimension is
very small, due to low distance to the tunnel border, the model
boundary conditions affect the estimated amount of groundwater flow
into the tunnel and results show a very high inflow to tunnel. Hence,
in this study, the two-dimensional universal distinct element code
(UDEC) used and the impact of different model parameters, such as
tunnel radius, joint spacing, horizontal and vertical model domain
extent has been evaluated. Results show that the model domain extent
is a function of the most significant parameters, which are tunnel
radius and joint spacing.
Abstract: An innovative concept called “Flexy-Energy” is developing at 2iE. This concept aims to produce electricity at lower cost by smartly mix different available energy sources in accordance to the load profile of the region. With a higher solar irradiation and due to the fact that Diesel generator are massively used in sub-Saharan rural areas, PV/Diesel hybrid systems could be a good application of this concept and a good solution to electrify this region, provided they are reliable, cost effective and economically attractive to investors. Presentation of the developed approach is the aims of this paper. The PV/Diesel hybrid system designed consists to produce electricity and/or heat from a coupling between Diesel Diesel generators and PV panels without batteries storage, while ensuring the substitution of gasoil by bio-fuels available in the area where the system will be installed. The optimal design of this system is based on his technical performances; the Life Cycle Cost (LCC) and Levelized Cost of Energy are developed and use as economic criteria. The Net Present Value (NPV), the internal rate of return (IRR) and the discounted payback (DPB) are also evaluated according to dual electricity pricing (in sunny and unsunny hours). The PV/Diesel hybrid system obtained is compared to the standalone Diesel Diesel generators. The approach carried out in this paper has been applied to Siby village in Mali (Latitude 12 ° 23'N 8 ° 20'W) with 295 kWh as daily demand.This approach provides optimal physical characteristics (size of the components, number of component) and dynamical characteristics in real time (number of Diesel generator on, their load rate, fuel specific consumptions, and PV penetration rate) of the system. The system obtained is slightly cost effective; but could be improved with optimized tariffing strategies.
Abstract: This paper examines the effect of the volatility of oil
prices on food price in South Africa using monthly data covering the
period 2002:01 to 2014:09. Food price is measured by the South
African consumer price index for food while oil price is proxied by
the Brent crude oil. The study employs the GARCH-in-mean VAR
model, which allows the investigation of the effect of a negative and
positive shock in oil price volatility on food price. The model also
allows the oil price uncertainty to be measured as the conditional
standard deviation of a one-step-ahead forecast error of the change in
oil price. The results show that oil price uncertainty has a positive
and significant effect on food price in South Africa. The responses of
food price to a positive and negative oil price shocks is asymmetric.
Abstract: Real bronchial tree is very complicated piping system.
Analysis of flow and pressure losses in this system is very difficult.
Due to the complex geometry and the very small size in the lower
generations is examination by CFD possible only in the central part
of bronchial tree. For specify the pressure losses of lower generations
is necessary to provide a mathematical equation. Determination of
mathematical formulas for calculation of pressure losses in the real
lungs is time consuming and inefficient process due to its complexity
and diversity. For these calculations is necessary to slightly simplify
the geometry of lungs (same cross-section over the length of
individual generation) or use one of the idealized models of lungs
(Horsfield, Weibel). The article compares the values of pressure
losses obtained from CFD simulation of air flow in the central part of
the real bronchial tree with the values calculated in a slightly
simplified real lungs by using a mathematical relationship derived
from the Bernoulli and continuity equations. The aim of the article is
to analyse the accuracy of the analytical method and its possibility of
use for the calculation of pressure losses in lower generations, which
is difficult to solve by numerical method due to the small geometry.
Abstract: This paper reports the worldwide status of building
information modeling (BIM) adoption from the perspectives of the
engagement level, the Hype Cycle model, the technology diffusion
model, and BIM services. An online survey was distributed, and 156
experts from six continents responded. Overall, North America was
the most advanced continent, followed by Oceania and Europe.
Countries in Asia perceived their phase mainly as slope of
enlightenment (mature) in the Hype Cycle model. In the technology
diffusion model, the main BIM-users worldwide were “early majority”
(third phase), but those in the Middle East/Africa and South America
were “early adopters” (second phase). In addition, the more advanced
the country, the more number of BIM services employed in general. In
summary, North America, Europe, Oceania, and Asia were advancing
rapidly toward the mature stage of BIM, whereas the Middle
East/Africa and South America were still in the early phase. The
simple indexes used in this study may be used to track the worldwide
status of BIM adoption in long-term surveys.
Abstract: The work allowed gaining knowledge about redox and
speciation changes of As, Cr and Sb ionic forms in Klodnica River
water. This kind of studies never has been conducted in this region of
Poland. In study optimized and validated previously HPLC-ICP-MS
methods for determination of As, Sb and Cr was used. Separation
step was done using high-performance liquid chromatograph
equipped with ion-exchange column followed by ICP-MS
spectrometer detector. Preliminary studies included determination of
the total concentration of As, Sb and Cr, pH, Eh, temperature and
conductivity of the water samples. The study was conducted monthly
from March to August 2014, at six points on the Klodnica River. The
results indicate that exceeded at acceptable concentration of total Cr
and Sb was observed in Klodnica River and we should qualify
Klodnica River waters below the second purity class. In Klodnica
River waters dominates oxidized antimony and arsenic forms, as well
as the two forms of chromium Cr(VI) and Cr(III). Studies have also
shown the methyl derivative of arsenic's presence.
Abstract: In a multi-cultural learning context, where ties are
weak and dynamic, combining qualitative with quantitative research
methods may be more effective. Such a combination may also allow
us to answer different types of question, such as about people’s
perception of the network. In this study the use of observation,
interviews and photos were explored as ways of enhancing data from
social network questionnaires. Integrating all of these methods was
found to enhance the quality of data collected and its accuracy, also
providing a richer story of the network dynamics and the factors that
shaped these changes over time.
Abstract: Soil quality monitoring is a science-based soil
management tool that assesses soil ecosystem health.
A soil monitoring program in Auckland, New Zealand’s largest
city extends from 1995 to the present. The objective of this study was
to firstly determine changes in soil parameters (basic soil properties
and heavy metals) that were assessed from rural land in 1995-2000
and repeated in 2008-2012. The second objective was to determine
differences in soil parameters across various land uses including
native bush, rural (horticulture, pasture and plantation forestry) and
urban land uses using soil data collected in more recent years (2009-
2013).
Across rural land, mean concentrations of Olsen P had
significantly increased in the second sampling period and was
identified as the indicator of most concern, followed by soil
macroporosity, particularly for horticultural and pastoral land. Mean
concentrations of Cd were also greatest for pastoral and horticultural
land and a positive correlation existed between these two parameters,
which highlights the importance of analysing basic soil parameters in
conjunction with heavy metals. In contrast, mean concentrations of
As, Cr, Pb, Ni and Zn were greatest for urban sites. Native bush sites
had the lowest concentrations of heavy metals and were used to
calculate a ‘pollution index’ (PI). The mean PI was classified as high
(PI > 3) for Cd and Ni and moderate for Pb, Zn, Cr, Cu, As and Hg,
indicating high levels of heavy metal pollution across both rural and
urban soils. From a land use perspective, the mean ‘integrated
pollution index’ was highest for urban sites at 2.9 followed by
pasture, horticulture and plantation forests at 2.7, 2.6 and 0.9,
respectively.
It is recommended that soil sampling continues over time because
a longer spanning record will allow further identification of where
soil problems exist and where resources need to be targeted in the
future. Findings from this study will also inform policy and science
direction in regional councils.
Abstract: Morphological interaction of porcine cumulus-oocyte
complexes (pCOCs) was investigated on in vitro condition using
electron microscope (SEM and TEM). The totals of 1,923 oocytes
were round in shape, surrounded by Zona pellucida with layer of
cumulus cells ranging between 59.29-202.14 μm in size. They were
classified into intact-, multi-, partial cumulus cell layer oocyte, and
completely denuded oocyte, at the percentage composition of 22.80%
32.70%, 18.60%, and 25.90 % respectively. The pCOCs classified as
intact- and multi cumulus cell layer oocytes were further culturing at
37°C with 5% CO2, 95% air atmosphere and high humidity for 44 h
in M199 with Earle’s salts supplemented with 10% HTFCS, 2.2
mg/mL NaHCO3, 1 M Hepes, 0.25 mM pyruvate, 15 μg/mL porcine
follicle-stimulating hormone, 1 μg/mL LH, 1μg/mL estradiol with
ethanol, and 50 μg/mL gentamycin sulfate. On electron microscope
study, cumulus cells were found to stick their processes to secrete
substance from the sac-shape end into Zona pellucida of the oocyte
and also communicated with the neighboring cells through their
microvilli on the beginning of incubation period. It is believed that
the cumulus cells communicate with the oocyte by inserting the
microvilli through this gap and embedded in the oocyte cytoplasm
before secreting substance, through the sac-shape end of the
microvilli, to inhibit primary oocyte development at the prophase I.
Morphological changes of the complexes were observed after
culturing for 24-44 h. One hundred percentages of the cumulus layers
were expanded and cumulus cells were peeling off from the oocyte
surface. In addition, the round-shape cumulus cells transformed
themselves into either an elongate shape or a columnar shape, and no
communication between cumulus neighboring cells. After 44 h of
incubation time, diameter of oocytes surrounded by cumulus cells
was larger than 0 h incubation. The effect of hormones in culture
medium is exerted by their receptors present in porcine oocyte. It is
likely that all morphological changes of the complexes after hormone
treatment were to allow maturation of the oocyte. This study
demonstrated that the association of hormones in M199 could
promote porcine follicle activation in 44 h in vitro condition. This
culture system should be useful for studying the regulation of early
follicular growth and development, especially because these follicles represent a large source of oocytes that could be used in vitro for cell
technology.
Abstract: Teaching art by digital means is a big challenge for
the majority of teachers of art and design in primary schools, yet it
allows relationships between art, technology and creativity to be
clearly identified. The aim of this article is to present a modern way
of teaching art, using digital tools in the art classroom to improve
creative ability in pupils aged between nine and eleven years. It also
presents a conceptual model for creativity based on digital art. The
model could be useful for pupils interested in learning to draw by
using an e-drawing package, and for teachers who are interested in
teaching modern digital art in order to improve children’s creativity.
By illustrating the strategy of teaching art through technology, this
model may also help education providers to make suitable choices
about which technological approaches are most effective in
enhancing students’ creative ability, and which digital art tools can
benefit children by developing their technical skills. It is also
expected that use of this model will help to develop skills of social
interaction, which may in turn improve intellectual ability.
Abstract: Machining of hard materials is a recent technology for
direct production of work-pieces. The primary challenge in
machining these materials is selection of cutting tool inserts which
facilitates an extended tool life and high-precision machining of the
component. These materials are widely for making precision parts for
the aerospace industry. Nickel-based alloys are typically used in
extreme environment applications where a combination of strength,
corrosion resistance and oxidation resistance material characteristics
are required. The present paper reports the theoretical and
experimental investigations carried out to understand the influence of
machining parameters on the response parameters. Considering the
basic machining parameters (speed, feed and depth of cut) a study has
been conducted to observe their influence on material removal rate,
surface roughness, cutting forces and corresponding tool wear.
Experiments are designed and conducted with the help of Central
Composite Rotatable Design technique. The results reveals that for a
given range of process parameters, material removal rate is favorable
for higher depths of cut and low feed rate for cutting forces. Low feed
rates and high values of rotational speeds are suitable for better finish
and higher tool life.