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: The main purpose of this paper is to determine the
applicability of the constitutional social rights in the so-called
horizontal relations, i.e. the relations between private entities.
Nowadays the constitutional rights are more and more often violated
by private entities and not only by the state. The private entities
interfere with the privacy of individuals, limit their freedom of
expression or disturb their peaceful gatherings. International
corporations subordinate individuals in a way which may limit their
constitutional rights. These new realities determine the new role of
the constitution in protecting human rights.
The paper will aim at answering two important questions. Firstly,
are the private entities obliged to respect the constitutional social
rights of other private entities and can they be liable for violation of
these rights? Secondly, how the constitutional social rights can
receive horizontal effect? Answers to these questions will have a
significant meaning for the popularisation of the practice of applying
the Constitution among the citizens as well as for the courts which
settle disputes between them.
Abstract: A three-dimensional numerical model of
thermoelectric generator (TEG) modules attached to a large chimney
plate is proposed and solved numerically using a control volume based
finite difference formulation. The TEG module consists of a
thermoelectric generator, an elliptical pin-fin heat sink, and a cold
plate for water cooling. In the chimney, the temperature of flue gases is
450-650K. Although the TEG hot-side temperature and thus the
electric power output can be increased by inserting an elliptical pin-fin
heat sink into the chimney tunnel to increase the heat transfer area, the
pin fin heat sink would cause extra pumping power at the same time.
The main purpose of this study is to analyze the effects of geometrical
parameters on the electric power output and chimney pressure drop
characteristics. The effects of different operating conditions, including
various inlet velocities (Vin= 1, 3, 5 m/s), inlet temperatures (Tgas = 450,
550, 650K) and different fin height (0 to 150 mm) are discussed in
detail. The predicted numerical data for the power vs. current (P-I)
curve are in good agreement (within 11%) with the experimental data.
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: 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: 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: Robotics brings together several very different
engineering areas and skills. There are various types of robot such as
humanoid robot, mobile robots, remotely operated vehicles, modern
autonomous robots etc. This survey paper advocates the operation of a
robotic car (remotely operated vehicle) that is controlled by a mobile
phone (communicate on a large scale over a large distance even from
different cities). The person makes a call to the mobile phone placed
in the car. In the case of a call, if any one of the button is pressed, a
tone equivalent to the button pressed is heard at the other end of the
call. This tone is known as DTMF (Dual Tone Multiple Frequency).
The car recognizes this DTMF tone with the help of the phone stacked
in the car. The received tone is processed by the Arduino
microcontroller. The microcontroller is programmed to acquire a
decision for any given input and outputs its decision to motor drivers
in order to drive the motors in the forward direction or backward
direction or left or right direction. The mobile phone that makes a call
to cell phone stacked in the car act as a remote.
Abstract: Properties of Portland cement mixtures with various
fractions of metakaolin were studied. 10% of Portland cement CEM I
42.5 R was replaced by different fractions of high reactivity
metakaolin with defined chemical and mineralogical properties.
Various fractions of metakaolin were prepared by jet mill classifying
system. There is a clear trend between fineness of metakaolin and
hydration heat development. Due to metakaolin presence in mixtures
the compressive strength development of mortars is rather slower for
coarser fractions but 28-day flexural strengths are improved for all
fractions of metakaoline used in mixtures compared to reference
sample of pure Portland cement. Yield point, plastic viscosity and
adhesion of fresh pastes are considerably influenced by fineness of
metakaolin used in cement pastes.
Abstract: In this study, the Compressive strength of concretes
made with Ground Granulated Blast furnace Slag (GGBS),
Pulverised Fuel Ash (PFA), Rice Husk Ash (RHA) and Waste Glass
Powder (WGP) after they were exposed 7800C (exposure duration of
around 60 minutes) and then allowed to cool down gradually in the
furnace for about 280 minutes at water binder ratio of 0.50 was
investigated. GGBS, PFA, RHA and WGP were used to replace up to
20% Portland cement in the control concrete. Test for the
determination of workability, compressive strength and tensile
splitting strength of the concretes were carried out and the results
were compared with control concrete. The test results showed that the
compressive strength decreased by an average of around 30% after
the concretes were exposed to the heating and cooling scenario.
Abstract: Array-based gene expression analysis is a powerful
tool to profile expression of genes and to generate information on
therapeutic effects of new anti-cancer compounds. Anti-apoptotic
effect of thymoquinone was studied in MCF7 breast cancer cell line
using gene expression profiling with cDNA microarray. The purity
and yield of RNA samples were determined using RNeasyPlus Mini
kit. The Agilent RNA 6000 NanoLabChip kit evaluated the quantity
of the RNA samples. AffinityScript RT oligo-dT promoter primer
was used to generate cDNA strands. T7 RNA polymerase was used to
convert cDNA to cRNA. The cRNA samples and human universal
reference RNA were labelled with Cy-3-CTP and Cy-5-CTP,
respectively. Feature Extraction and GeneSpring softwares analysed
the data. The single experiment analysis revealed involvement of 64
pathways with up-regulated genes and 78 pathways with downregulated
genes. The MAPK and p38-MAPK pathways were
inhibited due to the up-regulation of PTPRR gene. The inhibition of
p38-MAPK suggested up-regulation of TGF-ß pathway. Inhibition of
p38-MAPK caused up-regulation of TP53 and down-regulation of
Bcl2 genes indicating involvement of intrinsic apoptotic pathway.
Down-regulation of CARD16 gene as an adaptor molecule regulated
CASP1 and suggested necrosis-like programmed cell death and
involvement of caspase in apoptosis. Furthermore, down-regulation
of GPCR, EGF-EGFR signalling pathways suggested reduction of
ER. Involvement of AhR pathway which control cytochrome P450
and glucuronidation pathways showed metabolism of Thymoquinone.
The findings showed differential expression of several genes in
apoptosis pathways with thymoquinone treatment in estrogen
receptor-positive breast cancer cells.
Abstract: The main aim of the presented experiments is to
improve behaviour of sandwich structures under dynamic loading,
such as crash or explosion. This paper describes experimental
investigation on the response of new advanced materials to low and
high velocity load. Blast wave energy absorbers were designed using
two types of porous lightweight raw particle materials based on
expanded glass and ceramics with dimensions of 0.5-1 mm,
combined with polymeric binder. The effect of binder amount on the
static and dynamic properties of designed materials was observed.
Prism shaped specimens were prepared and loaded to obtain physicomechanical
parameters – bulk density, compressive and flexural
strength under quasistatic load, the dynamic response was determined
using Split Hopkinson Pressure bar apparatus. Numerical
investigation of the material behaviour in sandwich structure was
performed using implicit/explicit solver LS-Dyna. As the last step,
the developed material was used as the interlayer of blast resistant
litter bin, and it´s functionality was verified by real field blast tests.
Abstract: Power Regeneration in Refrigeration Plant concept
has been analyzed and has been shown to be capable of saving about
25% power in Cryogenic Plants with the Power Regeneration System
(PRS) running under nominal conditions. The innovative component
Compressor Expander Group (CEG) based on turbomachinery has
been designed and built modifying CETT compressor and expander,
both selected for optimum plant performance. Experiments have
shown the good response of the turbomachines to run with R404a as
working fluid. Power saving up to 12% under PRS derated conditions
(50% loading) has been demonstrated. Such experiments allowed
predicting a power saving up to 25% under CEG full load.
Abstract: Using the pseudopotential technique the Sagdeev
potential equation has been derived in a plasma consisting of twotemperature
nonisothermal electrons, negatively charged dust grains
and warm positive ions. The study shows that the presence of
nonisothermal two-temperature electrons and charged dust grains
have significant effects on the excitation and structure of the ionacoustic
double layers in the model plasma under consideration. Only
compressive type double layer is obtained in the present plasma
model. The double layer solution has also been obtained by including
higher order nonlinearity and nonisothermality, which is shown to
modify the amplitude and deform the shape of the double layer.
Abstract: In the present work, fly ash geopolymer based
composites including polyester (PES) waste were studied. Specimens
of three compositions were prepared: (a) fly ash geopolymer with 5%
PES waste; (b) fly ash geopolymer mortar with 5% PES waste; (c) fly
ash geopolymer mortar with 6.25% PES waste. Compressive and
bending strength measurements, water absorption test and
determination of thermal conductivity coefficient were performed.
The results showed that the addition of sand in a mixture of
geopolymer with 5% PES content led to higher compressive strength,
while it increased water absorption and reduced thermal conductivity
coefficient. The increase of PES addition in geopolymer mortars
resulted in a more dense structure, indicated by the increase of
strength and thermal conductivity and the decrease of water
absorption.
Abstract: Exact solution of an unsteady flow of elastico-viscous
fluid through a porous media in a tube of ellipsoidal cross section
under the influence of constant pressure gradient has been obtained in
this paper. Initially, the flow is generated by a constant pressure
gradient. After attaining the steady state, the pressure gradient is
suddenly withdrawn and the resulting fluid motion in a tube of
ellipsoidal cross section by taking into account of the porosity factor
of the bounding surface is investigated. The problem is solved in twostages
the first stage is a steady motion in tube under the influence of
a constant pressure gradient, the second stage concern with an
unsteady motion. The problem is solved employing separation of
variables technique. The results are expressed in terms of a nondimensional
porosity parameter (K) and elastico-viscosity parameter
(β), which depends on the Non-Newtonian coefficient. The flow
parameters are found to be identical with that of Newtonian case as
elastic-viscosity parameter tends to zero and porosity tends to
infinity. It is seen that the effect of elastico-viscosity parameter and
the porosity parameter of the bounding surface has significant effect
on the velocity parameter.
Abstract: MSMEs are regarded as the sunrise sector of the
Indian economy in view of its large potential for growth and likely
socio economic impact specifically on employment and income
generation. In today’s competitive business environment, global
competition forces companies to continuously seek ways of
improving their products and services. The pressure on organizations
to adapt to new technologies and external threats requires
resourcefulness, creativity and innovation. Market has become more
open, competitive and customers more demanding. Without
continuous technology innovation, no organization can ever remain
competitive. Innovations reflect a critical way in which organizations
respond to either technological or market challenges. The need of the
market is to deliver high quality products through continuous
changing in features in product, improve existing products, reduce
their cost, and improve employee skills, training, technology
infrastructure and financial policies. Therefore, the key factor of
organization’s ability to change is innovation. The study presents a
detailed review of literature on the role of technology innovation in
improving manufacturing performance of industries.
Abstract: Skin aging is a slow multifactorial process influenced
by both internal as well as external factors. Ultra-violet radiations
(UV), diet, smoking and personal habits are the most common
environmental factors that affect skin aging. Fat contents and fibrous
proteins as collagen and elastin are core internal structural
components. The direct influence of UV on elastin integrity and
health is central on aging of skin especially by time. The deposition
of abnormal elastic material is a major marker in a photo-aged skin.
Searching for compounds that may protect against cutaneous photodamage
is exceedingly valued. Retinoids and alpha hydroxy acids
have been endorsed by some researchers as possible candidates for
protecting and or repairing the effect of UV damaged skin. For
consolidating a better system of anti- and protective effects of such
anti-aging agents, we evaluated the combinatory effects of various
dosages of lactic acid and retinol on the dermal fibroblast’s elastin
levels exposed to UV. The UV exposed cells showed significant
reduction in the elastin levels. A combination of drugs with a higher
concentration of lactic acid (30 -35 mM) and a lower concentration of
retinol (10-15mg/mL) showed to work better in maintaining elastin
concentration in UV exposed cells. We assume this preservation
could be the result of increased tropo-elastin gene expression
stimulated by retinol whereas lactic acid probably repaired the UV
irradiated damage by enhancing the amount and integrity of the
elastin fibers.
Abstract: Activated carbons (M4P0, M4P2, and M5P2) used in
this research were produced from palm shell and polyetherether
ketone (PEEK) via carbonization, impregnation and microwave
activation. The adsorption/desorption process was carried out using
static volumetric adsorption. Regeneration is important in the overall
economy of the process and waste minimization. This work focuses
on the thermal regeneration of the CO2 exhausted microwave
activated carbons. The regeneration strategy adopted was thermal
with nitrogen purge desorption with N2 feed flow rate of 20 ml/min
for 1 h at atmospheric pressure followed by drying at 150oC.Seven
successive adsorption/regeneration processes were carried out on the
material. It was found that after seven adsorption regeneration cycles;
the regeneration efficiency (RE) for CO2 activated carbon from palm
shell only (M4P0) was more than 90% while that of hybrid palm
shell-PEEK (M4P2, M5P2) was above 95%. The cyclic adsorption
and regeneration shows the stability of the adsorbent materials.
Abstract: Co metal supported on SiO2 and Al2O3 catalysts with
a metal loading varied from 30 of 70 wt.% were evaluated for
decomposition of methane to COx free hydrogen and carbon
nanomaterials. The catalytic runs were carried out from 550-800oC
under atmospheric pressure using fixed bed vertical flow reactor. The
fresh and spent catalysts were characterized by BET surface area
analyzer, XRD, SEM, TEM and TG analysis. The data showed that
50% Co/Al2O3 catalyst exhibited remarkable higher activity at 800oC
with respect to H2 production compared to rest of the catalysts.
However, the catalytic activity and durability was greatly declined at
higher temperature. The main reason for the catalytic inhibition of Co
containing SiO2 catalysts is the higher reduction temperature of
Co2SiO4. TEM images illustrate that the carbon materials with
various morphologies, carbon nanofibers (CNFs), helical-shaped
CNFs and branched CNFs depending on the catalyst composition and
reaction temperature were obtained.
Abstract: Diminished antioxidant defense or increased
production of reactive oxygen species in the biological system can
result in oxidative stress which may lead to various
neurodegenerative diseases including Alzheimer’s disease (AD).
Microglial activation also contributes to the progression of AD by
producing several proinflammatory cytokines, nitric oxide (NO) and
prostaglandin E2 (PGE2). Oxidative stress and inflammation have
been reported to be possible pathophysiological mechanisms
underlying AD. In addition, the cholinergic hypothesis postulates that
memory impairment in patient with AD is also associated with the
deficit of cholinergic function in the brain. Although a number of
drugs have been approved for the treatment of AD, most of these
synthetic drugs have diverse side effects and yield relatively modest
benefits. Marine algae have great potential in pharmaceutical and
biomedical applications as they are valuable sources of bioactive
properties such as anticoagulation, antimicrobial, antioxidative,
anticancer and anti-inflammatory. Hence, this study aimed to provide
an overview of the properties of Malaysian seaweeds (Padina
australis, Sargassum polycystum and Caulerpa racemosa) in
inhibiting oxidative stress, neuroinflammation and cholinesterase
enzymes. These seaweeds significantly exhibited potent DPPH and
moderate superoxide anion radical scavenging ability (P