Abstract: In the present study, Convective heat transfer
coefficient and pressure drop of Al2O3/water nanofluid in laminar
flow regime under constant heat flux conditions inside a circular tube
were experimentally investigated. Al2O3/water nanofluid with 0.5%
and 1% volume concentrations with 15 nm diameter nanoparticles
were used as working fluid. The effect of different volume
concentrations on convective heat transfer coefficient and friction
factor was studied. The results emphasize that increasing of particle
volume concentration leads to enhance convective heat transfer
coefficient. Measurements show the average heat transfer coefficient
enhanced about 11-20% with 0.5% volume concentration and
increased about 16-27% with 1% volume concentration compared to
distilled water. In addition, the convective heat transfer coefficient of
nanofluid enhances with increase in heat flux. From the results, the
average ratio of (fnf/fbf) was about 1.10 for 0.5% volume
concentration. Therefore, there is no significant increase in friction
factor for nanofluids.
Abstract: In recent five decades, textured yarns of polyester fiber produced by false twist method are the most
important and mass-produced manmade fibers. There are
many parameters of cross section which affect the physical and mechanical properties of textured yarns. These parameters
are surface area, perimeter, equivalent diameter, large
diameter, small diameter, convexity, stiffness, eccentricity, and hydraulic diameter. These parameters were evaluated by
digital image processing techniques. To find trends between production criteria and evaluated parameters of cross section, three criteria of production line have been adjusted and different types of yarns were produced. These criteria are
temperature, drafting ratio, and D/Y ratio. Finally the relations between production criteria and cross section parameters were
considered. The results showed that the presented technique can recognize and measure the parameters of fiber cross section in acceptable accuracy. Also, the optimum condition
of adjustments has been estimated from results of image analysis evaluation.
Abstract: Automatic keyphrase extraction is useful in efficiently
locating specific documents in online databases. While several
techniques have been introduced over the years, improvement on
accuracy rate is minimal. This research examines attribute scores for
author-supplied keyphrases to better understand how the scores affect
the accuracy rate of automatic keyphrase extraction. Five attributes
are chosen for examination: Term Frequency, First Occurrence, Last
Occurrence, Phrase Position in Sentences, and Term Cohesion
Degree. The results show that First Occurrence is the most reliable
attribute. Term Frequency, Last Occurrence and Term Cohesion
Degree display a wide range of variation but are still usable with
suggested tweaks. Only Phrase Position in Sentences shows a totally
unpredictable pattern. The results imply that the commonly used
ranking approach which directly extracts top ranked potential phrases
from candidate keyphrase list as the keyphrases may not be reliable.
Abstract: Acoustic Imaging based sound localization using microphone
array is a challenging task in digital-signal processing.
Discrete Fourier transform (DFT) based near-field acoustical holography
(NAH) is an important acoustical technique for sound source
localization and provide an efficient solution to the ill-posed problem.
However, in practice, due to the usage of small curtailed aperture
and its consequence of significant spectral leakage, the DFT could
not reconstruct the active-region-of-sound (AROS) effectively, especially
near the edges of aperture. In this paper, we emphasize the
fundamental problems of DFT-based NAH, provide a solution to
spectral leakage effect by the extrapolation based on linear predictive
coding and 2D Tukey windowing. This approach has been tested to
localize the single and multi-point sound sources. We observe that
incorporating extrapolation technique increases the spatial resolution,
localization accuracy and reduces spectral leakage when small curtail
aperture with a lower number of sensors accounts.
Abstract: In this paper we use data mining techniques to investigate factors that contribute significantly to enhancing the risk of acute coronary syndrome. We assume that the dependent variable is diagnosis – with dichotomous values showing presence or absence of disease. We have applied binary regression to the factors affecting the dependent variable. The data set has been taken from two different cardiac hospitals of Karachi, Pakistan. We have total sixteen variables out of which one is assumed dependent and other 15 are independent variables. For better performance of the regression model in predicting acute coronary syndrome, data reduction techniques like principle component analysis is applied. Based on results of data reduction, we have considered only 14 out of sixteen factors.
Abstract: The purposes of this study are to study political
information exposure, politicians- perceptions, political attitudes and
political participations among people in Bangkok Metropolitan Area.
The sample consisted of 420 which were selected by using accidental sampling method. Questionnaires were administered to all of the
respondents to obtain the data for this research. T-test, one-way ANOVA and Pearson-s correlation coefficient were used to analyze the data. The findings are as follows: The difference in gender,
education, income and occupation has significantly effect upon political information exposures. The difference in age, income has
significantly effect upon politicians- perceptions. The difference in income has significantly effect upon political attitudes. The
difference in gender, income and occupation has significantly effect
upon political participations. There were a significantly relations between political information exposures, political attitudes, political
participations and between politicians- perceptions, political attitudes and political participations.
Abstract: In the last decades, the problem of perforation
damage has been considered as the major factor for the
reduction of oil productivity. Underbalance perforation is
considered as one of the best means to minimize or overcome
this problem. By maintaining wellbore pressure lower than
formation pressure, perforation damage could be minimize or
eliminated. This can be achieved by the use of nontraditional
lightweight completion fluid. This paper presents the effect of
natural clay in formulating nontraditional completion fluid to
ensure successful perforation job and increase of production
rate. Natural clay is used as homogenizing agent to create a
stable and non-damaging low-density completion fluid.
Results indicate that the addition of natural clay dramatically
increase the stability of the final fluids. In addition, field test
has shown that the application of nontraditional completion
fluid increases oil production by three folds.
Abstract: The purpose of this study was to assess the value of Second Life among post-secondary instructors with experience using Second Life as an educational tool. Using Everett Rogers-s diffusion of innovations theory, survey respondents (N = 162), were divided into three adopter categories: innovators, early adopters and the early majority. Respondents were from 15 countries and 25 academic disciplines, indicating the considerable potential this innovation has to be adopted across many different borders and in many areas of academe. Nearly 94% of respondents said they plan to use Second Life again as an educational tool. However, no significant differences were found in instructors- levels of satisfaction with Second Life as an educational tool or their perceived effect on student learning across adopter categories. On the other hand, instructors who conducted class fully in Second Life were significantly more satisfied than those who used Second Life as only a small supplement to a real-world class. Overall, personal interest factors, rather than interpersonal communication factors, most influenced respondents- decision to adopt Second Life as an educational tool. In light of these findings, theoretical implications are discussed and practical suggestions are provided.
Abstract: This paper focuses on the experimental impacts of
ultrasonic, carbonate and a combination of them on the quality of
fresh kiwi juice. Today, non-thermal methods like ultrasonic, which
have imperceptible effects on some properties of the juice such as
taste, flavor and color, are commonly used for killing
microorganisms.In this paper, some properties of kiwi fruit juice
under ultrasonic, carbonate and a combination of them has been
researched. Those properties include pH, acidity, transparency and
Brix. Its impact on microorganisms has been studied as well.The
results show that using a combination of carbonate and sonicate make
the cavitation more severe without a perceptible effect on nonactivation
of microorganisms.
Abstract: Salary risk and demographic risk have been identified
as main risks in analyzing pension expenditure particularly in
Defined Benefit pension plan. Therefore, public pension plan in
Malaysia is studied to analyze pension expenditure due to salary and
demographic risk. Through the literature review and interview session
with several officers in public sector, factors affecting pension
expenditure are determined. Then, the inter-relationships between
these factors are analyzed through causal loop diagram. The System
Dynamics model is later developed using iThink software to show how
demographic and salary changes affect the pension expenditure. Then, by
using actual data, the impact of different policy scenarios on pension
expenditure is analyzed. It is shown that dynamics simulation model of
pension expenditure is useful to evaluate the impact of changes and
policy decisions on risk particularly involving demographic and salary risk.
Abstract: This study was designed to determine effect of
supplemented tomato pomace and fobrolytic enzyme on egg
production and egg quality. A total of 40 CP brown laying hens (95
week old) were used in completely randomized design in 2x2
factorial arrangement with or without enzyme supplementation. Four
dietary treatments included: Control (C), Fibrolytic enzyme (FE),
10% Tomato pomace (TP), and Fibrolytic enzyme + 10 % Tomato
pomace (FE+TP). Each of the four dietary treatments was fed up to
30 days (10 birds/treatment). Live performance, egg production, egg
weight and quality were determined for whole period. Dietary
treatments had no effect (P>0.05) on live performance, egg weight,
yolk color, and egg production. Therefore, laying hens fed diets with
fibrolytic enzyme were significantly (P
Abstract: A lot of computer-based methods have been developed
to assess the evacuation capability (EC) of high-rise buildings.
Because softwares are time-consuming and not proper for on scene
applications, we adopted two methods, fuzzy analytic hierarchy
process (FAHP) and technique for order preference by similarity to an
ideal solution (TOPSIS), for EC assessment of a high-rise building in
Jinan. The EC scores obtained with the two methods and the
evacuation time acquired with Pathfinder 2009 for floors 47-60 of the
building were compared with each other. The results show that FAHP
performs better than TOPSIS for EC assessment of high-rise buildings,
especially in the aspect of dealing with the effect of occupant type and
distance to exit on EC, tackling complex problem with multi-level
structure of criteria, and requiring less amount of computation.
However, both FAHP and TOPSIS failed to appropriately handle the
situation where the exit width changes while occupants are few.
Abstract: This work aims to test the application of computational fluid dynamics (CFD) modeling to fixed bed catalytic cracking reactors. Studies of CFD with a fixed bed design commonly use a regular packing with N=2 to define bed geometry. CFD allows us to obtain a more accurate view of the fluid flow and heat transfer mechanisms present in fixed bed equipment. Naphtha was used as feedstock and the reactor length was 80cm. It is divided in three sections that catalyst bed packed in the middle section of the reactor. The reaction scheme was involved one primary reaction and 24 secondary reactions. Because of high CPU times in these simulations, parallel processing have been used. In this study the coke formation process in fixed bed and empty tube reactor was simulated and coke in these reactors are compared. In addition, the effect of steam ratio and feed flow rate on coke formation was investigated.
Abstract: This research studied recycled wastes by Recyclable Material Bank project of 17 universities of Thailand for evaluation of reducing greenhouse gasses emission compared with landfilling activity during January 2011 to December 2011. The results showed that the projects collected total amount of recyclable wastes about 1,626.917 metric ton. The office paper has the largest amount among these recycled wastes (55.61 % of total recycled wastes). Groups of recycled waste can be prioritized from high to low according to their amount as paper, plastic, glass, mixed recyclables and metal, respectively. The project reduced greenhouse gasses emission equivalent to about 5,263.481 metric ton of carbon dioxide. The most significant recycled waste that affects the reduction of greenhouse gasses emission is office paper which is 73.45% of total reduced greenhouse gasses emission. According to amount of reduced greenhouse gasses emission, groups of recycled waste can be prioritized from high to low significances as paper, plastic, metal, mixed recyclables and glass, respectively.
Abstract: There have been significant improvements in automatic
voice recognition technology. However, existing systems still face difficulties,
particularly when used by non-native speakers with accents.
In this paper we address a problem of identifying the English accented
speech of speakers from different backgrounds. Once an accent is
identified the speech recognition software can utilise training set from
appropriate accent and therefore improve the efficiency and accuracy
of the speech recognition system. We introduced the Q factor, which
is defined by the sum of relationships between frequencies of the
formants. Four different accents were considered and experimented
for this research. A scoring method was introduced in order to
effectively analyse accents. The proposed concept indicates that the
accent could be identified by analysing their formants.
Abstract: Residual dye contents in textile dyeing wastewater have complex aromatic structures that are resistant to degrade in biological wastewater treatment. The objectives of this study were to determine the effectiveness of nanoscale zerovalent iron (NZVI) to decolorize Reactive Black 5 (RB5) and Reactive Red 198 (RR198) in synthesized wastewater and to investigate the effects of the iron particle size, iron dosage and solution pHs on the destruction of RB5 and RR198. Synthesized NZVI was confirmed by transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The removal kinetic rates (kobs) of RB5 (0.0109 min-1) and RR198 (0.0111 min-1) by 0.5% NZVI were many times higher than those of microscale zerovalent iron (ZVI) (0.0007 min-1 and 0.0008 min-1, respectively). The iron dosage increment exponentially increased the removal efficiencies of both RB5 and RR198. Additionally, lowering pH from 9 to 5 increased the decolorization kinetic rates of both RB5 and RR198 by NZVI. The destruction of azo bond (N=N) in the chromophore of both reactive dyes led to decolorization of dye solutions.
Abstract: A comprehensive program of laboratory testing on a
compacted kaolin in a modified triaxial cell was perform to
investigate the influence of hydraulic hysteresis on effective stress in
unsaturated soils. The test data are presented on a range of constant
suction shear tests along wetting and drying paths. The values of
effective stress parameter χ at different matric suction were
determined using the test results. The effect of hydraulic hysteresis
phenomenon on the effective stress was observed. The values of
effective stress parameter χ obtained from the experiments were
compared with those obtained from the expressions proposed in
literature.
Abstract: This paper describes a finite-difference time-domainFDTD) method to analyze lightning surge propagation in electric transmission lines. Numerical computation of solving the Telegraphist-s equations is determined and investigated its effectiveness. A source of lightning surge wave on power transmission lines is modeled by using Heidler-s surge model. The
proposed method was tested against medium-voltage power
transmission lines in comparison with the solution obtained by using
lattice diagram. As a result, the calculation showed that the method is one of accurate methods to analyze transient
lightning wave in power transmission lines.
Abstract: The paper presents the virtual model of the active
suspension system used for improving the dynamic behavior of a
motor vehicle. The study is focused on the design of the control
system, the purpose being to minimize the effect of the road
disturbances (which are considered as perturbations for the control
system). The analysis is performed for a quarter-car model, which
corresponds to the suspension system of the front wheel, by using the
DFC (Design for Control) software solution EASY5 (Engineering
Analysis Systems) of MSC Software. The controller, which is a PIDbased
device, is designed through a parametric optimization with the
Matrix Algebra Tool (MAT), considering the gain factors as design
variables, while the design objective is to minimize the overshoot of
the indicial response.
Abstract: The emergence of person-centred discourse based
around notions of 'personal development planning- and 'work'life
balance' has taken hold in education and the workplace in recent
years. This paper examines this discourse with regard to recent
developments in higher education as well as the inter-related issue of
work-life balance in occupational careers. In both cases there have
been national and trans-national policy initiatives directed towards
improving both personal opportunities and competitive advantage in
a global knowledge-based economy. However, despite an increasing
concern with looking outward at this globalised educational and
employment marketplace, there is something of a paradox in
encouraging people to look inward at themselves in order to become
more self-determined. This apparent paradox is considered from a
discourse analytic perspective in terms of the ideological effects of an
increasing concern with the personal world. Specifically, it is argued
that there are tensions that emerge from a concern with an innerdirected
process of self-reflection that dissolve any engagement with
wider political issues that impact upon educational and career
development.