Abstract: In this paper, modeling of an acoustic enclosed
vehicle cabin has been carried out by using boundary element
method. Also, the second purpose of this study is analyzing of linear
wave equation in an acoustic field. The resultants of this modeling
consist of natural frequencies that have been compared with
resultants derived from finite element method. By using numerical
method (boundary element method) and after solution of wave
equation inside an acoustic enclosed cabin, this method has been
progressed to simulate noise inside a simple vehicle cabin.
Abstract: Brushless DC motor with high torque density and slim
topology for easy loading for robot system is proposed and
manufactured. Electromagnetic design is executed by equivalent
magnetic circuit model and numerical analysis. Manufactured motor is
tested and verified characteristics comparing with conventional BLDC
motor.
Abstract: In this paper a study on the vibration of thin
cylindrical shells with ring supports and made of functionally
graded materials (FGMs) composed of stainless steel and
nickel is presented. Material properties vary along the
thickness direction of the shell according to volume fraction
power law. The cylindrical shells have ring supports which are
arbitrarily placed along the shell and impose zero lateral
deflections. The study is carried out based on third order shear
deformation shell theory (T.S.D.T). The analysis is carried out
using Hamilton-s principle. The governing equations of motion of
FGM cylindrical shells are derived based on shear deformation
theory. Results are presented on the frequency characteristics,
influence of ring support position and the influence of boundary
conditions. The present analysis is validated by comparing results
with those available in the literature.
Abstract: In this paper a novel ultra-wideband (UWB) slot antenna with band notch characteristics for world interoperability for microwave access (WiMAX) is proposed. The designed antenna consists of a rectangular radiating patch and a ground plane with tapered shape slot. To realize a notch band, a curved parasitic element has been etched out along with the radiating patch. It is observed that by adjusting the length, thickness and position of the parasitic element, the proposed antenna can achieved an impedance bandwidth of 8.01GHz (2.84 to 10.85GHz) with a notched band of 3.28-3.85GHz. Compared to the recently reported band notch antennas, the proposed antenna has a simple configuration to realize band notch characteristics in order to mitigate the potential interference between WiMAX and UWB system. Furthermore, a stable radiation pattern and moderate gain except at the notched band makes the proposed antenna suitable for various UWB applications.
Abstract: In recent years fuel cell vehicles are rapidly appearing
all over the globe. In less than 10 years, fuel cell vehicles have gone
from mere research novelties to operating prototypes and demonstration
models. At the same time, government and industry in development
countries have teamed up to invest billions of dollars in partnerships
intended to commercialize fuel cell vehicles within the early
years of the 21st century.
The purpose of this study is evaluation of model and performance
of fuel cell hybrid electric vehicle in different drive cycles. A fuel
cell system model developed in this work is a semi-experimental
model that allows users to use the theory and experimental relationships
in a fuel cell system. The model can be used as part of a complex
fuel cell vehicle model in advanced vehicle simulator (ADVISOR).
This work reveals that the fuel consumption and energy efficiency
vary in different drive cycles. Arising acceleration and speed in a
drive cycle leads to Fuel consumption increase. In addition, energy
losses in drive cycle relates to fuel cell system power request. Parasitic
power in different parts of fuel cell system will increase when
power request increases. Finally, most of energy losses in drive cycle
occur in fuel cell system because of producing a lot of energy by fuel
cell stack.
Abstract: Ascorbic acid (AA), commonly known as vitamin C, is essential for normal functioning of the body and maintenance of metabolic integrity. Among its various roles are as an antioxidant, a cofactor in collagen formation and other reactions, as well as reducing physical stress and maintenance of the immune system. Recent collaborative research between the Australian Defence Science and Technology Organisation (DSTO) in Scottsdale, Tasmania and RMIT University has sought to overcome the problems arising from the inherent instability of ascorbic acid during processing and storage of foods. The recent work has demonstrated the potential of microencapsulation by spray drying as a means to enhance retention. The purpose of this current study has been focused upon the influence of spray drying conditions on the properties of encapsulated ascorbic acid. The process was carried out according to a central composite design. Independent variables were: inlet temperature (80-120° C) and feed flow rate (7-14 mL/minute). Process yield, ascorbic acid loss, moisture content, water activity and particle size distribution were analysed as responses. The results have demonstrated the potential of microencapsulation by spray drying as a means to enhance retention. Vitamin retention, moisture content, water activity and process yield were influenced positively by inlet air temperature and negatively by feed flow rate.
Abstract: The freezing point of milk is in important indicator of
the milk quality. The freezing point of milk is determined primarily
to prove milk adulteration with water and to determine the amount of
water in it. Chemical composition and properties of milk, thermal
treatment and presence of any substance can influence freezing point
of product. There are different substances, which can be added to
milk with main purpose to prolong shelf-life of raw milk. There are
detergent, preservatives, formaldehyde, hydrogen peroxide,
antibiotics, sodium carbonate, and hydrogen peroxide. Therefore the
aim of the present study was to determine freezing point of milk,
skimmed milk, pasteurized milk and milk with different substances
(formaldehyde, antibiotics, sodium carbonate, hydrogen peroxide,
disinfectant, and detergent) in different concentrations. The thermal
treatment and different undesirable substances presence in milk have
significant influence on freezing point of it.
Abstract: This contribution was developed from a research
within the doctoral thesis. Its object was to create multimedia
materials for sport gymnastics. Consequently we surveyed the
influence of its practical application on the efficiency of schooling at
a university. We verified the prescribed hypothesis of the efficiency
of the teaching process using the method of single-factor experiment,
where the entrance independent variable was the change of system of
tuition and the outgoing dependent variable was the change of level
of acquired motor skills. The results confirmed the positive impact of
using multimedia materials on the efficiency of the teaching process.
Further, with the aid of questionnaires, we evaluated how the tested
subjects perceive the innovative methods in sport gymnastics. The
responses showed that the students rate the application of multimedia
materials very positively.
Abstract: Biometrics, which refers to identifying an individual
based on his or her physiological or behavioral characteristics, has
the capability to reliably distinguish between an authorized person
and an imposter. Signature verification systems can be categorized as
offline (static) and online (dynamic). This paper presents a neural
network based recognition of offline handwritten signatures system
that is trained with low-resolution scanned signature images.
Abstract: This paper presents a simple three phase power flow
method for solution of three-phase unbalanced radial distribution
system (RDN) with voltage dependent loads. It solves a simple
algebraic recursive expression of voltage magnitude, and all the data
are stored in vector form. The algorithm uses basic principles of
circuit theory and can be easily understood. Mutual coupling between
the phases has been included in the mathematical model. The
proposed algorithm has been tested with several unbalanced radial
distribution networks and the results are presented in the article. 8-
bus and IEEE 13 bus unbalanced radial distribution system results
are in agreements with the literature and show that the proposed
model is valid and reliable.
Abstract: Recent environmental turbulence including financial
crisis, intensified competitive forces, rapid technological change and
high market turbulence have dramatically changed the current
business climate. The managers firms have to plan and decide what
the best approaches that best fit their firms in order to pursue superior
performance. This research aims to examine the influence of strategic
reasoning and top level managers- individual characteristics on the
effectiveness of organizational improvisation and firm performance.
Given the lack of studies on these relationships in the previous
literature, there is significant contribution to the body of knowledge
as well as for managerial practices. 128 responses from top
management of technology-based companies in Malaysia were used
as a sample. Three hypotheses were examined and the findings
confirm that (a) there is no relationship between intuitive reasoning
and organizational improvisation but there is a link between rational
reasoning and organizational improvisation, (b) top level managers-
individual characteristics as a whole affect organizational
improvisation; and (c) organizational improvisation positively affects
firm performance. The theoretical and managerial implications were
discussed in the conclusions.
Abstract: In this paper a new robust digital image watermarking
algorithm based on the Complex Wavelet Transform is proposed. This
technique embeds different parts of a watermark into different blocks
of an image under the complex wavelet domain. To increase security
of the method, two chaotic maps are employed, one map is used to
determine the blocks of the host image for watermark embedding,
and another map is used to encrypt the watermark image. Simulation
results are presented to demonstrate the effectiveness of the proposed
algorithm.
Abstract: The paper deals with the development of portable aerosol concentrator and its application for the determination of nitrites and nitrates. The device enables the continuous trapping of pollutants in the air. An extensive literature search has been elaborated which aims at the development of samplers and the possibilities of their application in the continuous determination of volatile organic compounds. The practical part of the paper is focused on the development of the portable aerosol concentrator. The device using the Aerosol Enrichment Unit has been experimentally verified and subsequently realized. It operates on the principle of equilibrium accumulation of pollutants from the gaseous phase using absorption liquid polydisperse aerosol. The device has been applied for monitoring nitrites and nitrates in the air. The chemiluminescence detector was used for detection; the achieved detection limit for nitrites was 28 ng/m3 and for nitrates 78 ng/m3.
Abstract: In this paper we introduce an effective ECG compression algorithm based on two dimensional multiwavelet transform. Multiwavelets offer simultaneous orthogonality, symmetry and short support, which is not possible with scalar two-channel wavelet systems. These features are known to be important in signal processing. Thus multiwavelet offers the possibility of superior performance for image processing applications. The SPIHT algorithm has achieved notable success in still image coding. We suggested applying SPIHT algorithm to 2-D multiwavelet transform of2-D arranged ECG signals. Experiments on selected records of ECG from MIT-BIH arrhythmia database revealed that the proposed algorithm is significantly more efficient in comparison with previously proposed ECG compression schemes.
Abstract: Microscopic emission and fuel consumption models
have been widely recognized as an effective method to quantify real
traffic emission and energy consumption when they are applied with
microscopic traffic simulation models. This paper presents a
framework for developing the Microscopic Emission (HC, CO, NOx,
and CO2) and Fuel consumption (MEF) models for light-duty
vehicles. The variable of composite acceleration is introduced into
the MEF model with the purpose of capturing the effects of historical
accelerations interacting with current speed on emission and fuel
consumption. The MEF model is calibrated by multivariate
least-squares method for two types of light-duty vehicle using
on-board data collected in Beijing, China by a Portable Emission
Measurement System (PEMS). The instantaneous validation results
shows the MEF model performs better with lower Mean Absolute
Percentage Error (MAPE) compared to other two models. Moreover,
the aggregate validation results tells the MEF model produces
reasonable estimations compared to actual measurements with
prediction errors within 12%, 10%, 19%, and 9% for HC, CO, NOx
emissions and fuel consumption, respectively.
Abstract: An adaptive Chinese hand-talking system is presented
in this paper. By analyzing the 3 data collecting strategies for new
users, the adaptation framework including supervised and unsupervised
adaptation methods is proposed. For supervised adaptation,
affinity propagation (AP) is used to extract exemplar subsets, and enhanced
maximum a posteriori / vector field smoothing (eMAP/VFS)
is proposed to pool the adaptation data among different models. For
unsupervised adaptation, polynomial segment models (PSMs) are
used to help hidden Markov models (HMMs) to accurately label
the unlabeled data, then the "labeled" data together with signerindependent
models are inputted to MAP algorithm to generate
signer-adapted models. Experimental results show that the proposed
framework can execute both supervised adaptation with small amount
of labeled data and unsupervised adaptation with large amount
of unlabeled data to tailor the original models, and both achieve
improvements on the performance of recognition rate.
Abstract: We propose a phenomenological model for the
process of polymer desorption. In so doing, we omit the usual
theoretical approach of incorporating a fictitious viscoelastic
stress term into the flux equation. As a result, we obtain a
model that captures the essence of the phenomenon of trapping
skinning, while preserving the integrity of the experimentally
verified Fickian law for diffusion. An appropriate asymptotic
analysis is carried out, and a parameter is introduced to represent
the speed of the desorption front. Numerical simulations are
performed to illustrate the desorption dynamics of the model.
Recommendations are made for future modifications of the
model, and provisions are made for the inclusion of experimentally
determined frontal speeds.
Abstract: This paper presents a new Quality-Controlled, wavelet based, compression method for electrocardiogram (ECG) signals. Initially, an ECG signal is decomposed using the wavelet transform. Then, the resulting coefficients are iteratively thresholded to guarantee that a predefined goal percent root mean square difference (GPRD) is matched within tolerable boundaries. The quantization strategy of extracted non-zero wavelet coefficients (NZWC), according to the combination of RLE, HUFFMAN and arithmetic encoding of the NZWC and a resulting look up table, allow the accomplishment of high compression ratios with good quality reconstructed signals.
Abstract: Email has become a fast and cheap means of online
communication. The main threat to email is Unsolicited Bulk Email
(UBE), commonly called spam email. The current work aims at
identification of unigrams in more than 2700 UBE that advertise
body-enhancement drugs. The identification is based on the
requirement that the unigram is neither present in dictionary, nor is a
slang term. The motives of the paper are many fold. This is an
attempt to analyze spamming behaviour and employment of wordmutation
technique. On the side-lines of the paper, we have
attempted to better understand the spam, the slang and their interplay.
The problem has been addressed by employing Tokenization
technique and Unigram BOW model. We found that the non-lexicon
words constitute nearly 66% of total number of lexis of corpus
whereas non-slang words constitute nearly 2.4% of non-lexicon
words. Further, non-lexicon non-slang unigrams composed of 2
lexicon words, form more than 71% of the total number of such
unigrams. To the best of our knowledge, this is the first attempt to
analyze usage of non-lexicon non-slang unigrams in any kind of
UBE.
Abstract: This paper proposes a stroke extraction method for use in off-line signature verification. After giving a brief overview of the current ongoing researches an algorithm is introduced for detecting and following strokes in static images of signatures. Problems like the handling of junctions and variations in line width and line intensity are discussed in detail. Results are validated by both using an existing on-line signature database and by employing image registration methods.