Abstract: This paper treats a discrete-time batch arrival queue with single working vacation. The main purpose of this paper is to present a performance analysis of this system by using the supplementary variable technique. For this purpose, we first analyze the Markov chain underlying the queueing system and obtain its ergodicity condition. Next, we present the stationary distributions of the system length as well as some performance measures at random epochs by using the supplementary variable method. Thirdly, still based on the supplementary variable method we give the probability generating function (PGF) of the number of customers at the beginning of a busy period and give a stochastic decomposition formulae for the PGF of the stationary system length at the departure epochs. Additionally, we investigate the relation between our discretetime system and its continuous counterpart. Finally, some numerical examples show the influence of the parameters on some crucial performance characteristics of the system.
Abstract: A biosensor based on glucose oxidase (GOx) immobilized onto nanoparticles zirconium oxide with polyethylene nanocomposite for glucose monitoring has been designed. The CTAB/PEG/ZrO2/GOx nanocomposite was deposited onto screen printed carbon paste (SPCE) electrode via spin coating technique. The properties of CTAB/PEG/ZrO2/GOx were study using scanning electron microscopy (SEM). The SPE modified with the CTAB/PEG/ZrO2/GOx showed electrocatalytical response to the oxidation of glucose when ferrocene carboxaldehyde was used as an artificial redox mediator, which was studied by cyclic voltammetry (CV). Several parameters such as working potential, effect of pH and effect of ZrO2/PEG layers that governed the analytical performance of the biosensor, have been studied. The biosensor was applied to detect glucose with a linear range of 0.4 to 2.0 mmol L−1 with good repetability and reproducibility.
Abstract: Antimicrobial (AM) starch-based films were
developed by incorporating chitosan and lauric acid as antimicrobial
agent into starch-based film. Chitosan has wide range of applications
as a biomaterial, but barriers still exist to its broader use due to its
physical and chemical limitations. In this work, a series of
starch/chitosan (SC) blend films containing 8% of lauric acid was
prepared by casting method. The structure of the film was
characterized by Fourier transform infrared spectroscopy (FTIR), Xray
diffraction (XRD), and scanning electron microscopy (SEM).
The results indicated that there were strong interactions were present
between the hydroxyl groups of starch and the amino groups of
chitosan resulting in a good miscibility between starch and chitosan
in the blend films. Physical properties and optical properties of the
AM starch-based film were evaluated. The AM starch-based films
incorporated with chitosan and lauric acid showed an improvement in
water vapour transmission rate (WVTR) and addition of starch
content provided more transparent films while the yellowness of the
film attributed to the higher chitosan content. The improvement in
water barrier properties was mainly attributed to the hydrophobicity
of lauric acid and optimum chitosan or starch content. AM starch
based film also showed excellent oxygen barrier. Obtaining films
with good oxygen permeability would be an indication of the
potential use of these antimicrobial packaging as a natural packaging
and an alternative packaging to the synthetic polymer to protect food
from oxidation reactions
Abstract: This study analyses the perceptions of secondary
school students about the accounting profession in Malaysia. Fifty
five form three and form four students who are taking
accounting/commerce subjects were met. Individual-s perception
data were collected through questionnaires. The results at the
secondary school level suggest that the stereotypical negative image
of the accountant ends, with students expressing the positive view of
the work of an accountant. There were also gender differences in
perceiving the accounting profession. Overall, the results of the study
suggest that we are now in line in projecting positive and accurate
perceptions of the accounting profession to secondary school
students.
Abstract: For many industrial applications plate heat
exchangers are demonstrating a large superiority over the
other types of heat exchangers. The efficiency of such a
device depends on numerous factors the effect of which needs
to be analysed and accurately evaluated.
In this paper we present a theoretical analysis of a cocurrent
plate heat exchanger and the results of its numerical
simulation.
Knowing the hot and the cold fluid streams inlet temperatures,
the respective heat capacities mCp
and the value of the
overall heat transfer coefficient, a 1-D mathematical model
based on the steady flow energy balance for a differential
length of the device is developed resulting in a set of N first
order differential equations with boundary conditions where N
is the number of channels.For specific heat exchanger
geometry and operational parameters, the problem is
numerically solved using the shooting method.
The simulation allows the prediction of the temperature
map in the heat exchanger and hence, the evaluation of its
performances. A parametric analysis is performed to evaluate
the influence of the R-parameter on the e-NTU values. For
practical purposes effectiveness-NTU graphs are elaborated
for specific heat exchanger geometry and different operating
conditions.
Abstract: The objective of this paper is to analyse the
application of the Half-Sweep Gauss-Seidel (HSGS) method by using
the Half-sweep approximation equation based on central difference
(CD) and repeated trapezoidal (RT) formulas to solve linear fredholm
integro-differential equations of first order. The formulation and
implementation of the Full-Sweep Gauss-Seidel (FSGS) and Half-
Sweep Gauss-Seidel (HSGS) methods are also presented. The HSGS
method has been shown to rapid compared to the FSGS methods.
Some numerical tests were illustrated to show that the HSGS method
is superior to the FSGS method.
Abstract: Malaria is a serious, acute and chronic relapsing
infection to humans. It is characterized by periodic attacks of chills,
fever, nausea, vomiting, back pain, increased sweating anemia,
splenomegaly (enlargement of the spleen) and often-fatal
complications.The malaria disease is caused by the multiplication of
protozoa parasite of the genus Plasmodium. Malaria in humans is due
to 4 types of malaria parasites such that Plasmodium falciparum,
Plasmodium vivax, Plasmodium malariae and Plasmodium ovale.
P.vivax malaria differs from P. falciparum malaria in that a person
suffering from P. vivax malaria can experience relapses of the
disease. Between the relapses, the malaria parasite will remain
dormant in the liver of the patient, leading to the patient being
classified as being in the dormant class. A mathematical model for
the transmission of P. vivax is developed in which the human
population is divided into four classes, the susceptible, the infected,
the dormant and the recovered. In this paper, we formulate the
dynamical model of P. vivax malaria to see the distribution of this
disease at the district level.
Abstract: This paper presents the Literature Review of carbon fiber reinforced polymer (CFRP) strips to reinforced concrete (RC) as a strengthening solution for T-beams. Although a great deal of research has been carried out on Rectangular beams strengthened with Fibre-Reinforced Polymer composites (FRP), Fiber reinforced polymer (FRP) composites have been increasingly studied for their application in the flexural or shear strengthening of reinforced concrete (RC) members. A detailed discussion of the shearstrengthening repair with FRP is undertaken. This paper will be limited to research of CFRP material externally bonded to the tensile face of concrete beams. In particular, research studying the effect of externally applied CFRP materials on the shear performance of reinforced concrete beams will be reported.
Abstract: Today, any organization - regardless of the specific activity - must be prepared to face continuous radical changes, innovation thus becoming a condition of survival in a globalized market. Few managers have a wider vision that includes innovation, to enable better performance of the critical activities, namely the degree of novelty that it must submit an innovation to be considered as such. Companies need not only radical changes in the products or their services, but also to their business strategies. Not all managers have an overall view on the real size of necessary innovation potential. Unfortunately there is still no common understanding (and correct) of the term of innovation among managers. Moreover, not all managers are aware of the need for innovation. In these conditions, increasing the processes adaptability of firms (through innovation) to meet the needs and performance requirements is difficult without a systematic framework. To overcome this disadvantage, the authors propose a framework for designing an innovation management system,, to cover all the important aspects of a business system, to reach the actual performance of an organization.
Abstract: In this paper, the robust exponential stability problem of uncertain discrete-time recurrent neural networks with timevarying delay is investigated. By constructing a new augmented Lyapunov-Krasovskii function, some new improved stability criteria are obtained in forms of linear matrix inequality (LMI). Compared with some recent results in literature, the conservatism of the new criteria is reduced notably. Two numerical examples are provided to demonstrate the less conservatism and effectiveness of the proposed results.
Abstract: Activated carbon was prepared from agricultural waste “almond (Prunus amygdalus) nut shells" by chemical activation with phosphoric acid as an activating agent at 450 °C for 24 hr soaking time. The physical and chemical properties were analyzed. The adsorption of chromium VI from aqueous solution on almond nut shell activated carbon (ASAC) was investigated. The adsorption process parameters pH, agitation speed, agitation time, adsorbent dose were optimized. 98% of Cr VI was sorbed at pH 2 and stirring speed 200 rpm.. Surface structure showed that ASAC has a spongy type structure showing large number of pores
Abstract: We study the dynamic response of a wind turbine
structure subjected to theoretical seismic motions, taking into account
the rotational component of ground shaking. Models are generated
for a shallow moderate crustal earthquake in the Madrid Region
(Spain). Synthetic translational and rotational time histories are
computed using the Discrete Wavenumber Method, assuming a point
source and a horizontal layered earth structure. These are used to
analyze the dynamic response of a wind turbine, represented by a
simple finite element model. Von Mises stress values at different
heights of the tower are used to study the dynamical structural
response to a set of synthetic ground motion time histories
Abstract: New Zealand-s product markets experienced a surge in
import competition beginning from the late 1970-s when its
government began to promote a policy of more open markets. This
study considers how the trade liberalization aspect of the policy may
have influenced unionization and union-organizing success. For
describing the trade liberalization, a model shows how the removal of
import tariffs can lead to countervailing influences upon the union
membership of a domestic firm. The evidence supports the prediction
that union membership has been decreased rather than increased. In
the context of debates concerning globalization, it can be said that the
power of unions has been diminished.
Abstract: Middle-gate is located in Hasankeyf, Batman dating
back to 1800 BC and is one of the important historical structures in
Turkey. The ancient structure has suffered major structural cracks
due to aging as well as lateral pressure of a cracked rock which is
predicted to be about 100 tons. The existing support system was
found to be inadequate to support the load especially after a recent
rock fall in the close vicinity. Concerns were increased since the
existing support system that is integral with a damaged and cracked
gate wall needed to be replaced by a new support system. The
replacement process must be carefully monitored by crackmeters and
control mechanisms should be integrated to prevent cracks to expand
while the same crack width needs to be maintained after the
operation. The control system and actions taken during the
intervention are explained in this paper.
Abstract: Vinegar or sour wine is a product of alcoholic and
subsequent acetous fermentation of sugary precursors derived from
several fruits or starchy substrates. This delicious food additive and
supplement contains not less than 4 grams of acetic acid in 100 cubic
centimeters at 20°C. Among the large number of bacteria that are
able to produce acetic acid, only few genera are used in vinegar
industry most significant of which are Acetobacter and
Gluconobacter. In this research we isolated and identified an
Acetobacter strain from Iranian apricot, a very delicious and sensitive
summer fruit to decay, we gathered from fruit's stores in Isfahan,
Iran. The main culture media we used were Carr, GYC, Frateur and
an industrial medium for vinegar production. We isolated this strain
using a novel miniature fermentor we made at Pars Yeema
Biotechnologists Co., Isfahan Science and Technology Town (ISTT),
Isfahan, Iran. The microscopic examinations of isolated strain from
Iranian apricot showed gram negative rods to cocobacilli. Their
catalase reaction was positive and oxidase reaction was negative and
could ferment ethanol to acetic acid. Also it showed an acceptable
growth in 5%, 7% and 9% ethanol concentrations at 30°C using
modified Carr media after 24, 48 and 96 hours incubation
respectively. According to its tolerance against high concentrations of
ethanol after four days incubation and its high acetic acid production,
8.53%, after 144 hours, this strain could be considered as a suitable
industrial strain for a production of a new type of vinegar, apricot
vinegar, with a new and delicious taste. In conclusion this is the first
report of isolation and identification of an Acetobacter strain from
Iranian apricot with a very good tolerance against high ethanol
concentrations as well as high acetic acid productivity in an
acceptable incubation period of time industrially. This strain could be
used in vinegar industry to convert apricot spoilage to a beneficiary
product and mentioned characteristics have made it as an amenable
strain in food and agricultural biotechnology.
Abstract: Among the various cooling processes in industrial
applications such as: electronic devices, heat exchangers, gas
turbines, etc. Gas turbine blades cooling is the most challenging one.
One of the most common practices is using ribbed wall because of
the boundary layer excitation and therefore making the ultimate
cooling. Vortex formation between rib and channel wall will result in
a complicated behavior of flow regime. At the other hand, selecting
the most efficient method for capturing the best results comparing to
experimental works would be a fascinating issue. In this paper 4
common methods in turbulence modeling: standard k-e, rationalized
k-e with enhanced wall boundary layer treatment, k-w and RSM
(Reynolds stress model) are employed to a square ribbed channel to
investigate the separation and thermal behavior of the flow in the
channel. Finally all results from different methods which are used in
this paper will be compared with experimental data available in
literature to ensure the numerical method accuracy.
Abstract: Continuous measurements and multivariate methods are applied in researching the effects of energy consumption on indoor air quality (IAQ) in a Finnish one-family house. Measured data used in this study was collected continuously in a house in Kuopio, Eastern Finland, during fourteen months long period. Consumption parameters measured were the consumptions of district heat, electricity and water. Indoor parameters gathered were temperature, relative humidity (RH), the concentrations of carbon dioxide (CO2) and carbon monoxide (CO) and differential air pressure. In this study, self-organizing map (SOM) and Sammon's mapping were applied to resolve the effects of energy consumption on indoor air quality. Namely, the SOM was qualified as a suitable method having a property to summarize the multivariable dependencies into easily observable two-dimensional map. Accompanying that, the Sammon's mapping method was used to cluster pre-processed data to find similarities of the variables, expressing distances and groups in the data. The methods used were able to distinguish 7 different clusters characterizing indoor air quality and energy efficiency in the study house. The results indicate, that the cost implications in euros of heating and electricity energy vary according to the differential pressure, concentration of carbon dioxide, temperature and season.
Abstract: The issue of human anthropology took an important
role in the last epochs and still hasn-t lost its importance. Scientists of
different countries were interested in investigating the appearance of
human being and the idea of life after death. While writing this article
we noticed that scientists who made research in this issue, despite of
the different countries and different epochs in which they lived, had
similarities in their opinions. In given article we wrote great Kazakh
poet AbaiKunanbayev-s philosophical view to the problem of human
anthropology.
Abstract: The globalization of the Indian economy has thrown a great challenge to the Indian industries in respect of productivity, quality, cost, delivery etc. Achieving success• the global market has required fundamental shift in the way business is conducted and has dramatically affected virtually every aspect of process industry. The internal manufacturing process and supporting infrastructure should be such that it can compete successfully in global markets with better flexibility and delivery. The paper deals with a case study of a reputed process industry, some changes in the process has been suggested, which leads to reduction in labor cost and production cost.
Abstract: This work presents a study on the abrasive water jet
(AWJ) machining. An explicit finite element analysis (FEA) of
single abrasive particle impact on stainless steel 1.4304 (AISI 304) is
conducted. The abrasive water jet machining is modeled by FEA
software ABAQUS/CAE. Shapes of craters in FEM simulation
results were used and compared with the previous experimental and
FEM works by means of crater sphericity. The influence of impact
angle and particle velocity was observed. Adaptive mesh domain is
used to model the impact zone. Results are in good agreement with
those obtained from the experimental and FEM simulation. The
crater-s depth is also obtained for different impact angle and abrasive
particle velocities.