Abstract: In this paper, we propose a fixed formatting method of PPX(Pretty Printer for XML). PPX is a query language for XML database which has extensive formatting capability that produces HTML as the result of a query. The fixed formatting method is to completely specify the combination of variables and layout specification operators within the layout expression of the GENERATE clause of PPX. In the experiment, a quick comparison shows that PPX requires far less description compared to XSLT or XQuery programs doing the same tasks.
Abstract: IEEE 802.15.4a impulse radio-time hopping ultra wide
band (IR-TH UWB) physical layer, due to small duty cycle and very
short pulse widths is robust against multipath propagation. However,
scattering and reflections with the large number of obstacles in indoor
channel environments, give rise to dense multipath fading. It imposes
serious problem to optimum Rake receiver architectures, for which
very large number of fingers are needed. Presence of strong noise
also affects the reception of fine pulses having extremely low power
spectral density. A robust SRake receiver for IEEE 802.15.4a IRTH
UWB in dense multipath and additive white Gaussian noise
(AWGN) is proposed to efficiently recover the weak signals with
much reduced complexity. It adaptively increases the signal to noise
(SNR) by decreasing noise through a recursive least square (RLS)
algorithm. For simulation, dense multipath environment of IEEE
802.15.4a industrial non line of sight (NLOS) is employed. The power
delay profile (PDF) and the cumulative distribution function (CDF)
for the respective channel environment are found. Moreover, the error
performance of the proposed architecture is evaluated in comparison
with conventional SRake and AWGN correlation receivers. The
simulation results indicate a substantial performance improvement
with very less number of Rake fingers.
Abstract: The counter flow solar air heaters, with four
transverse fins and wire mesh layers are constructed and investigated
experimentally for thermal efficiency at a geographic location of
Cyprus in the city of Famagusta. The absorber plate is replaced by
sixteen steel wire mesh layers, 0.18 x 0.18cm in cross section
opening and a 0.02cm in diameter. The wire mesh layers arranged in
three groups, first and second include 6 layers, while the third include
4 layers. All layers fixed in the duct parallel to the glazing and each
group separated from the others by wood frame thickness of 0.5cm to
reduce the pressure drop. The transverse fins arranged in a way to
force the air to flow through the bed like eight letter path with flow
depth 3cm. The proposed design has increased the heat transfer rate,
but on other hand causes a high pressure drop. The obtained results
show that, for air mass flow rate range between 0.011-0.036kg/s, the
thermal efficiency increases with increasing the air mass flow. The
maximum efficiency obtained is 65.6% for the mass flow rate of
0.036kg/s. Moreover, the temperature difference between the outlet
flow and the ambient temperature, ΔT, reduces as the air mass flow
rate increase. The maximum difference between the outlet and
ambient temperature obtained was 43°C for double pass for minimum
mass flow rate of 0.011kg/s. Comparison with a conventional solar
air heater collector shows a significantly development in the thermal
efficiency.
Abstract: Tasks of the work were study the possible E.coli
contamination in red deer meat, identify pathogenic strains from
isolated E.coli, determine their incidence in red deer meat and
determine the presence of VT1, VT2 and eaeA genes for the
pathogenic E.coli. 8 (10%) samples were randomly selected from 80
analysed isolates of E.coli and PCR reaction was performed on them.
PCR was done both on initial materials – samples of red deer meat -
and for already isolated liqueurs. Two of analysed venison samples
contain verotoxin-producing strains of E. coli. It means that this meat
is not safe to consumer. It was proven by the sequestration reaction of
E. coli and by comparison of the obtained results with the database of
microorganism genome available on the internet that the isolated
culture corresponds to region 16S rDNS of E. coli thus presenting
correctness of the microbiological methods.
Abstract: The paper structures research approaches to the crisis
and its management. It focuses on approaches – psychological,
sociological, economic, ethical and technological. Furthermore, it
describes the basic features of models chosen according to those
approaches. By their comparison it shows how the crisis influences
organizations and individuals, and their mutual interaction.
Abstract: To improve the dynamics response of the vehicle
passive suspension, a two-terminal mass is suggested to connect in
parallel with the suspension strut. Three performance criteria, tire grip,
ride comfort and suspension deflection, are taken into consideration to
optimize the suspension parameters. However, the three criteria are
conflicting and non-commensurable. For this reason, the Chebyshev
goal programming method is applied to find the best tradeoff among
the three objectives. A simulation case is presented to describe the
multi-objective optimization procedure. For comparison, the
Chebyshev method is also employed to optimize the design of a
conventional passive suspension. The effectiveness of the proposed
design method has been clearly demonstrated by the result. It is also
shown that the suspension with a two-terminal mass in parallel has
better performance in terms of the three objectives.
Abstract: Mobile WiMAX is a broadband wireless solution that
enables convergence of mobile and fixed broadband networks
through a common wide area broadband radio access technology and
flexible network architecture. It adopts Orthogonal Frequency
Division Multiple Access (OFDMA) for improved multi-path
performance in Non-Line-Of-Sight (NLOS) environments. Scalable
OFDMA (SOFDMA) is introduced in the IEEE 802e[1]. WIMAX
system uses one of different types of channel coding but The
mandatory channel coding scheme is based on binary nonrecursive
Convolutional Coding (CC). There are other several optional channel
coding schemes such as block turbo codes, convolutional turbo
codes, and low density parity check (LDPC).
In this paper a comparison between the performance of WIMAX
using turbo code and using convolutional product code (CPC) [2] is
made. Also a combination between them had been done. The CPC
gives good results at different SNR values compared to both the
turbo system, and the combination between them. For example, at
BER equal to 10-2 for 128 subcarriers, the amount of improvement
in SNR equals approximately 3 dB higher than turbo code and equals
approximately 2dB higher than the combination respectively. Several
results are obtained at different modulating schemes (16QAM and
64QAM) and different numbers of sub-carriers (128 and 512).
Abstract: The characteristic bending strength (MOR) and mean
modulus of elasticity (MOE) of tropical hardwood red seraya (Shorea
spp.) plywood were determined using European Standard EN310 and
EN789. The thickness of the test specimen was 4.0mm, 7.0mm,
9.0mm, 12.0mm and 15.0mm. The experiment found that the MOR
of red seraya plywood in EN310 is about 12% to 20% and 7% to
24% higher than EN789 whereas MOE were about 28% to 41% and
30% to 36% lower than those obtained from EN 789 for test
specimens parallel and perpendicular to the grain direction. The
linear regression shows that MOR and MOE for EN789 is about 0.8
times less and 1.5 times more than EN310. The experiment also
found that the MOR and MOE of EN310 and EN789 also depend on
the wood species that used in the experiment.
Abstract: This paper presents a modified version of the
maximum urgency first scheduling algorithm. The maximum
urgency algorithm combines the advantages of fixed and dynamic
scheduling to provide the dynamically changing systems with
flexible scheduling. This algorithm, however, has a major
shortcoming due to its scheduling mechanism which may cause a
critical task to fail. The modified maximum urgency first scheduling
algorithm resolves the mentioned problem. In this paper, we propose
two possible implementations for this algorithm by using either
earliest deadline first or modified least laxity first algorithms for
calculating the dynamic priorities. These two approaches are
compared together by simulating the two algorithms. The earliest
deadline first algorithm as the preferred implementation is then
recommended. Afterwards, we make a comparison between our
proposed algorithm and maximum urgency first algorithm using
simulation and results are presented. It is shown that modified
maximum urgency first is superior to maximum urgency first, since it
usually has less task preemption and hence, less related overhead. It
also leads to less failed non-critical tasks in overloaded situations.
Abstract: The paper presents a set of guidelines for analysis of industrial embedded distributed systems and introduces a mathematical model derived from these guidelines. In this study, the author examines a set of modern communication technologies that are or possibly can be used to build communication links between the subsystems of a distributed embedded system. An investigation of these guidelines results in a algorithm for analysis of specific use cases of target technologies. A goal of the paper acts as an important base for ongoing research on comparison of communication technologies. The author describes the principles of the model and presents results of the test calculations. Practical implementation of target technologies and empirical experiment data are based on a practical experience during the design and test of specific distributed systems in Latvian market.
Abstract: Each new semiconductor technology node
brings smaller transistors and wires. Although this makes
transistors faster, wires get slower. In nano-scale regime, the
standard copper (Cu) interconnect will become a major hurdle
for FPGA interconnect due to their high resistivity and
electromigration. This paper presents the comprehensive
evaluation of mixed CNT bundle interconnects and
investigates their prospects as energy efficient and high speed
interconnect for future FPGA routing architecture. All
HSPICE simulations are carried out at operating frequency of
1GHz and it is found that mixed CNT bundle implemented in
FPGAs as interconnect can potentially provide a substantial
delay and energy reduction over traditional interconnects at
32nm process technology.
Abstract: For micro-gyroscopes, the angular rate detection components have to oscillate forwards and backwards alternatively. An innovative design of micro-electromagnetic drive module is proposed to make a Π-type disc reciprocally and efficiently rotate within a certain of angular interval. Twelve Electromagnetic poles enclosing the thin disc are designed to provide the magnetic drive power. Isotropic etching technique is employed to fabricate the high-aspect-ratio trench, so that the contact angle of wire against trench can be increased and the potential defect of cavities and pores within the wire can be prevented. On the other hand, a Π-type thin disc is designed to conduct the pitch motion as an angular excitation, in addition to spinning, is exerted on the gyroscope. The efficacy of the micro-magnetic drive module is verified by the commercial software, Ansoft Maxewll. In comparison with the conventional planar windings in micro-scale systems, the magnetic drive force is increased by 150%.
Abstract: Research papers are usually evaluated via peer
review. However, peer review has limitations in evaluating research
papers. In this paper, Scienstein and the new idea of 'collaborative
document evaluation' are presented. Scienstein is a project to
evaluate scientific papers collaboratively based on ratings, links,
annotations and classifications by the scientific community using the
internet. In this paper, critical success factors of collaborative
document evaluation are analyzed. That is the scientists- motivation
to participate as reviewers, the reviewers- competence and the
reviewers- trustworthiness. It is shown that if these factors are
ensured, collaborative document evaluation may prove to be a more
objective, faster and less resource intensive approach to scientific
document evaluation in comparison to the classical peer review
process. It is shown that additional advantages exist as collaborative
document evaluation supports interdisciplinary work, allows
continuous post-publishing quality assessments and enables the
implementation of academic recommendation engines. In the long
term, it seems possible that collaborative document evaluation will
successively substitute peer review and decrease the need for
journals.
Abstract: This paper describes the results of an extensive study
and comparison of popular hash functions SHA-1, SHA-256,
RIPEMD-160 and RIPEMD-320 with JERIM-320, a 320-bit hash
function. The compression functions of hash functions like SHA-1
and SHA-256 are designed using serial successive iteration whereas
those like RIPEMD-160 and RIPEMD-320 are designed using two
parallel lines of message processing. JERIM-320 uses four parallel
lines of message processing resulting in higher level of security than
other hash functions at comparable speed and memory requirement.
The performance evaluation of these methods has been done by using
practical implementation and also by using step computation
methods. JERIM-320 proves to be secure and ensures the integrity of
messages at a higher degree. The focus of this work is to establish
JERIM-320 as an alternative of the present day hash functions for the
fast growing internet applications.
Abstract: Cassava bagasse is one of major biomass wastes in Thailand from starch processing industry, which contains high starch content of about 60%. The object of this study was to investigate the optimal condition for hydrothermally pretreating cassava baggasses with or without acid addition. The pretreated samples were measured reducing sugar yield directly or after enzymatic hydrolysis (alpha-amylase). In enzymatic hydrolysis, the highest reducing sugar content was obtained under hydrothermal conditions for at 125oC for 30 min. The result shows that pretreating cassava baggasses increased the efficiency of enzymatic hydrolysis. For acid hydrolysis, pretreating cassava baggasses with sulfuric acid at 120oC for 60 min gave a maximum reducing sugar yield. In this study, sulfuric acid had a greater capacity for hydrolyzing cassava baggasses than phosphoric acid. In comparison, dilute acid hydrolysis to provide a higher yield of reducing sugar than the enzymatic hydrolysis combined hydrothermal pretreatment. However, enzymatic hydrolysis in a combination with hydrothermal pretreatment was an alternative to enhance efficiency reducing sugar production from cassava bagasse.
Abstract: Wide applicability of concurrent programming
practices in developing various software applications leads to
different concurrency errors amongst which data race is the most
important. Java provides greatest support for concurrent
programming by introducing various concurrency packages. Aspect
oriented programming (AOP) is modern programming paradigm
facilitating the runtime interception of events of interest and can be
effectively used to handle the concurrency problems. AspectJ being
an aspect oriented extension to java facilitates the application of
concepts of AOP for data race detection. Volatile variables are
usually considered thread safe, but they can become the possible
candidates of data races if non-atomic operations are performed
concurrently upon them. Various data race detection algorithms have
been proposed in the past but this issue of volatility and atomicity is
still unaddressed. The aim of this research is to propose some
suggestions for incorporating certain conditions for data race
detection in java programs at the volatile fields by taking into account
support for atomicity in java concurrency packages and making use
of pointcuts. Two simple test programs will demonstrate the results
of research. The results are verified on two different Java
Development Kits (JDKs) for the purpose of comparison.
Abstract: Our objective in this paper is to propose an approach
capable of clustering web messages. The clustering is carried out by
assigning, with a certain probability, texts written by the same web
user to the same cluster based on Stylometric features and using
fuzzy clustering algorithms. Focus in the present work is on
comparing the most popular algorithms in fuzzy clustering theory
namely, Fuzzy C-means, Possibilistic C-means and Fuzzy
Possibilistic C-Means.
Abstract: In this paper we study some numerical methods to solve a model one-dimensional convection–diffusion equation. The semi-discretisation of the space variable results into a system of ordinary differential equations and the solution of the latter involves the evaluation of a matrix exponent. Since the calculation of this term is computationally expensive, we study some methods based on Krylov subspace and on Restrictive Taylor series approximation respectively. We also consider the Chebyshev Pseudospectral collocation method to do the spatial discretisation and we present the numerical solution obtained by these methods.
Abstract: A numerical investigation of the effects of nanosecond
barrier discharge on the stability of a two-dimensional free shear layer
is performed. The computations are carried out using a compressible
Navier-Stokes algorithm coupled with a thermodynamic model of the
discharge. The results show that significant increases in the shear
layer-s momentum thickness and Reynolds stresses occur due to
actuation. Dependence on both frequency and amplitude of actuation
are considered, and a comparison is made of the computed growth
rates with those predicted by linear stability theory. Amplitude and
frequency ranges for the efficient promotion of shear-layer instabilities
are identified.
Abstract: In this work, an attempt is made to design an optimal
wind/pv/diesel hybrid power system for a village of Ain Merane,
Chlef, Algeria, where the wind speed and solar radiation
measurements were made. The aim of this paper is the optimization
of a hybrid wind/solar/diesel system applied in term of technical and
economic feasibility by simulation using HOMER. A comparison
was made between the performance of wind/pv/diesel system and the
classic connecting system.