Abstract: The main purpose of this work was verify the
influence of the accelerated carbonation in the physical and
mechanical properties of the hybrid composites, reinforced with
micro and nanofibers and composites with microfibers. The
composites were produced by the slurry vacuum dewatering method,
followed by pressing. It was produced using two formulations: 8% of
eucalyptus pulp + 1% of the nanofibrillated cellulose and 9% of
eucalyptus pulp, both were subjected to accelerated carbonation. The
results showed that the accelerated carbonation contributed to
improve the physical and mechanical properties of the hybrid
composites and of the composites reinforced with microfibers
(eucalyptus pulp).
Abstract: Monocopter is a single-wing rotary flying vehicle
which has the capability of hovering. This flying vehicle includes two
dynamic parts in which more efficiency can be expected rather than
other Micro UAVs due to the extended area of wing compared to its
fuselage. Low cost and simple mechanism in comparison to other
vehicles such as helicopter are the most important specifications of
this flying vehicle.
In the previous paper we discussed the introduction of the final
system but in this paper, the experimental design process of
Monocopter and its control algorithm has been investigated in
general. Also the editorial bugs in the previous article have been
corrected and some translational ambiguities have been resolved.
Initially by constructing several prototypes and carrying out many
flight tests the main design parameters of this air vehicle were
obtained by experimental measurements. Eventually the required
main monocopter for this project was constructed. After construction
of the monocopter in order to design, implementation and testing of
control algorithms first a simple optic system used for determining
the heading angle. After doing numerous tests on Test Stand, the
control algorithm designed and timing of applying control inputs
adjusted. Then other control parameters of system were tuned in
flight tests. Eventually the final control system designed and
implemented using the AHRS sensor and the final operational tests
performed successfully.
Abstract: Urban public spaces are sutured with a range of
surveillance and sensor technologies that claim to enable new forms
of ‘data based citizen participation’, but also increase the tendency
for ‘function-creep’, whereby vast amounts of data are gathered,
stored and analysed in a broad application of urban surveillance. This
kind of monitoring and capacity for surveillance connects with
attempts by civic authorities to regulate, restrict, rebrand and reframe
urban public spaces. A direct consequence of the increasingly
security driven, policed, privatised and surveilled nature of public
space is the exclusion or ‘unfavourable inclusion’ of those considered
flawed and unwelcome in the ‘spectacular’ consumption spaces of
many major urban centres. In the name of urban regeneration,
programs of securitisation, ‘gentrification’ and ‘creative’ and ‘smart’
city initiatives refashion public space as sites of selective inclusion
and exclusion. In this context of monitoring and control procedures,
in particular, children and young people’s use of space in parks,
neighbourhoods, shopping malls and streets is often viewed as a
threat to the social order, requiring various forms of remedial action.
This paper suggests that cities, places and spaces and those who
seek to use them, can be resilient in working to maintain and extend
democratic freedoms and processes enshrined in Marshall’s concept
of citizenship, calling sensor and surveillance systems to account.
Such accountability could better inform the implementation of public
policy around the design, build and governance of public space and
also understandings of urban citizenship in the sensor saturated urban
environment.
Abstract: Creating a database scheme is essentially a manual
process. From a requirement specification the information contained
within has to be analyzed and reduced into a set of tables, attributes
and relationships. This is a time consuming process that has to go
through several stages before an acceptable database schema is
achieved. The purpose of this paper is to implement a Natural
Language Processing (NLP) based tool to produce a relational
database from a requirement specification. The Stanford CoreNLP
version 3.3.1 and the Java programming were used to implement the
proposed model. The outcome of this study indicates that a first draft
of a relational database schema can be extracted from a requirement
specification by using NLP tools and techniques with minimum user
intervention. Therefore this method is a step forward in finding a
solution that requires little or no user intervention.
Abstract: We report on the use of strong external optical
feedback to enhance the modulation response of semiconductor lasers
over a frequency passband around modulation frequencies higher
than 60 GHz. We show that this modulation enhancement is a type of
photon-photon resonance (PPR) of oscillating modes in the external
cavity formed between the laser and the external reflector. The study
is based on a time-delay rate equation model that takes into account
both the strong feedback and multiple reflections in the external
cavity. We examine the harmonic and intermodulation distortions
associated with single and two-tone modulations in the mm-wave
band of the resonant modulation. We show that compared with
solitary lasers modulated around the carrier-photon resonance
frequency, the present mm-wave modulated signal has lower
distortions.
Abstract: We model and simulate the combined effect of fiber
dispersion and frequency chirp of a directly modulated high-speed
laser diode on the figures of merit of a non-amplified 40-Gbps optical
fiber link. We consider both the return to zero (RZ) and non-return to
zero (NRZ) patterns of the pseudorandom modulation bits. The
performance of the fiber communication system is assessed by the
fiber-length limitation due to the fiber dispersion. We study the
influence of replacing standard single-mode fibers by non-zero
dispersion-shifted fibers on the maximum fiber length and evaluate
the associated power penalty. We introduce new dispersion
tolerances for 1-dB power penalty of the RZ and NRZ 40-Gbps
optical fiber links.
Abstract: This study presents a cost-effective approach for rapid
fabricating modeling platforms utilized in fused deposition modeling
system. A small-batch production of modeling platforms about 20
pieces can be obtained economically through silicone rubber mold
using vacuum casting without applying the plastic injection molding.
The air venting systems is crucial for fabricating modeling platform
using vacuum casting. Modeling platforms fabricated can be used for
building rapid prototyping model after sandblasting. This study offers
industrial value because it has both time-effectiveness and
cost-effectiveness.
Abstract: Floods play a key role in landform evolution of an
area. This process is likely to alter the topography of the earth’s
surface. The present study area, Kota Bharu is very prone to floods
extends from upstream of Kelantan River near Kemubu to the
downstream area near Kuala Besar. These flood events which occur
every year in the study area exhibit a strong bearing on river
morphological set-up. In the present study, three satellite imageries of
different time periods have been used to manifest the post-flood
landform changes. The pre-processing of the images such as subset,
geometric corrections and atmospheric corrections were carried-out
using ENVI 4.5 followed by the analysis processes. Twenty sets of
cross sections were plotted using software Erdas 9.2, ERDAS and
ArcGis 10 for the all three images. The results show a significant
change in the length of the cross section which suggest that the
geomorphological processes play a key role in carving and shaping
the river banks during the floods.
Abstract: Today’s modern interconnected power system is
highly complex in nature. In this, one of the most important
requirements during the operation of the electric power system is the
reliability and security. Power and frequency oscillation damping
mechanism improve the reliability. Because of power system
stabilizer (PSS) low speed response against of major fault such as
three phase short circuit, FACTs devise that can control the network
condition in very fast time, are becoming popular. But FACTs
capability can be seen in a major fault present when nonlinear models
of FACTs devise and power system equipment are applied. To realize
this aim, the model of multi-machine power system with FACTs
controller is developed in MATLAB/SIMULINK using Sim Power
System (SPS) blockiest. Among the FACTs device, Static
synchronous series compensator (SSSC) due to high speed changes
its reactance characteristic inductive to capacitive, is effective power
flow controller. Tuning process of controller parameter can be
performed using different method. But Genetic Algorithm (GA)
ability tends to use it in controller parameter tuning process. In this
paper firstly POD controller is used to power oscillation damping.
But in this station, frequency oscillation dos not has proper damping
situation. So FOD controller that is tuned using GA is using that
cause to damp out frequency oscillation properly and power
oscillation damping has suitable situation.
Abstract: Using cold EGR method with variable venturi and
turbocharger has a very significant effect on reduction of NOX and
grime simultaneously. EGR cooler is one of the most important parts
in the cold EGR circuit. In this paper optimum design of cooler for
working in different percentages of EGR and for determining
optimum temperature of exhausted gases, growth of efficiency,
reduction of weight, dimension, expenditures, sediment and also
optimum performance by using gasoil which has significant amounts
of brimstone are investigated and optimized.
Abstract: In this paper, we study the rainfall using a time series
for weather stations in Nakhon Ratchasima province in Thailand by
various statistical methods to enable us to analyse the behaviour of
rainfall in the study areas. Time-series analysis is an important tool in
modelling and forecasting rainfall. The ARIMA and Holt-Winter
models were built on the basis of exponential smoothing. All the
models proved to be adequate. Therefore it is possible to give
information that can help decision makers establish strategies for the
proper planning of agriculture, drainage systems and other water
resource applications in Nakhon Ratchasima province. We obtained
the best performance from forecasting with the ARIMA
Model(1,0,1)(1,0,1)12.
Abstract: Search engine plays an important role in internet, to
retrieve the relevant documents among the huge number of web
pages. However, it retrieves more number of documents, which are
all relevant to your search topics. To retrieve the most meaningful
documents related to search topics, ranking algorithm is used in
information retrieval technique. One of the issues in data miming is
ranking the retrieved document. In information retrieval the ranking
is one of the practical problems. This paper includes various Page
Ranking algorithms, page segmentation algorithms and compares
those algorithms used for Information Retrieval. Diverse Page Rank
based algorithms like Page Rank (PR), Weighted Page Rank (WPR),
Weight Page Content Rank (WPCR), Hyperlink Induced Topic
Selection (HITS), Distance Rank, Eigen Rumor, Distance Rank Time
Rank, Tag Rank, Relational Based Page Rank and Query Dependent
Ranking algorithms are discussed and compared.
Abstract: This paper proposes a new technique to design a
fixed-structure robust loop shaping controller for the pneumatic
servosystem. In this paper, a new method based on a particle swarm
optimization (PSO) algorithm for tuning the weighting function
parameters to design an H∞ controller is presented. The PSO
algorithm is used to minimize the infinity norm of the transfer
function of the nominal closed loop system to obtain the optimal
parameters of the weighting functions. The optimal stability margin is
used as an objective in PSO for selecting the optimal weighting
parameters; it is shown that the proposed method can simplify the
design procedure of H∞ control to obtain optimal robust controller for
pneumatic servosystem. In addition, the order of the proposed
controller is much lower than that of the conventional robust loop
shaping controller, making it easy to implement in practical works.
Also two-degree-of-freedom (2DOF) control design procedure is
proposed to improve tracking performance in the face of noise and
disturbance. Result of simulations demonstrates the advantages of the
proposed controller in terms of simple structure and robustness
against plant perturbations and disturbances.
Abstract: The in-cylinder flow and mixture formations are
significant in view of today’s increasing concern on environmental
issues and stringent emission regulations. In this paper, the numerical
simulations of a SI engine at different engine speeds (2000-5000
rpm) at fixed intake flow pressure of 1 bar are studied using the AVL
FIRE software. The simulation results show that when the engine
speed at fixed intake flow pressure is increased, the volumetric
efficiency of the engine decreases. This is due to a richer fuel
conditions near the engine cylinder wall when engine speed is
increased. Significant effects of impingement are also noted on the
upper and side walls of the engine cylinder. These variations in
mixture formation before ignition could affect the thermodynamics
efficiency and specific fuel consumption that would lead to a reduced
engine performance.
Abstract: An algorithm is a well-defined procedure that takes
some input in the form of some values, processes them and gives the
desired output. It forms the basis of many other algorithms such as
searching, pattern matching, digital filters etc., and other applications
have been found in database systems, data statistics and processing,
data communications and pattern matching. This paper introduces
algorithmic “Enhanced Bidirectional Selection” sort which is
bidirectional, stable. It is said to be bidirectional as it selects two
values smallest from the front and largest from the rear and assigns
them to their appropriate locations thus reducing the number of
passes by half the total number of elements as compared to selection
sort.
Abstract: Ontologies provide a common understanding of a
specific domain of interest that can be communicated between people
and used as background knowledge for automated reasoning in a
wide range of applications. In this paper, we address the design of
multilingual ontologies following well-defined knowledge
engineering methodologies with the support of novel collaborative
development approaches. In particular, we present a collaborative
platform which allows ontologies to be developed incrementally in
multiple languages. This is made possible via an appropriate mapping
between language independent concepts and one lexicalization per
language (or a lexical gap in case such lexicalization does not exist).
The collaborative platform has been designed to support the
development of the Universal Knowledge Core, a multilingual
ontology currently in English, Italian, Chinese, Mongolian, Hindi and
Bangladeshi. Its design follows a workflow-based development
methodology that models resources as a set of collaborative objects
and assigns customizable workflows to build and maintain each
collaborative object in a community driven manner, with extensive
support of modern web 2.0 social and collaborative features.
Abstract: This paper aims to analyze the role of natural
language processing (NLP). The paper will discuss the role in the
context of automated data retrieval, automated question answer, and
text structuring. NLP techniques are gaining wider acceptance in real
life applications and industrial concerns. There are various
complexities involved in processing the text of natural language that
could satisfy the need of decision makers. This paper begins with the
description of the qualities of NLP practices. The paper then focuses
on the challenges in natural language processing. The paper also
discusses major techniques of NLP. The last section describes
opportunities and challenges for future research.
Abstract: The financial crises caused a collapse in prices of
most asset classes, raising the attention on alternative investments
such as sukuk, a smaller, fast growing but often misunderstood
market. We study diversification benefits of sukuk, their correlation
with other asset classes and the effects of their inclusion in
investment portfolios of institutional and retail investors, through a
comprehensive comparison of their risk/return profiles during and
after the financial crisis.
We find a beneficial performance adjusted for the specific
volatility together with a lower correlation especially during the
financial crisis. The distribution of sukuk returns is positively skewed
and leptokurtic, with a risk/return profile similarly to high yield
bonds. Overall, our results suggest that sukuk present diversification
opportunities, a significant volatility-adjusted performance and lower
correlations especially during the financial crisis.
Our findings are relevant for a number of institutional investors.
Long term investors, such as life insurers would benefit from sukuk’s
protective features during financial crisis yet keeping return and
growth opportunities, whereas banks would gain due to their role of
placers, advisors, market makers or underwriters.
Abstract: Regardless of the manufacturing process used,
subtractive or additive, material, purpose and application, produced
components are conventionally solid mass with more or less complex
shape depending on the production technology selected. Aspects
such as reducing the weight of components, associated with the low
volume of material required and the almost non-existent material
waste, speed and flexibility of production and, primarily, a high
mechanical strength combined with high structural performance, are
competitive advantages in any industrial sector, from automotive,
molds, aviation, aerospace, construction, pharmaceuticals, medicine
and more recently in human tissue engineering. Such features,
properties and functionalities are attained in metal components
produced using the additive technique of Rapid Prototyping from
metal powders commonly known as Selective Laser Melting (SLM),
with optimized internal topologies and varying densities. In order to
produce components with high strength and high structural and
functional performance, regardless of the type of application, three
different internal topologies were developed and analyzed using
numerical computational tools. The developed topologies were
numerically submitted to mechanical compression and four point
bending testing. Finite Element Analysis results demonstrate how
different internal topologies can contribute to improve mechanical
properties, even with a high degree of porosity relatively to fully
dense components. Results are very promising not only from the
point of view of mechanical resistance, but especially through the
achievement of considerable variation in density without loss of
structural and functional high performance.
Abstract: In this paper, the formulation of a new group explicit
method with a fourth order accuracy is described in solving the two
dimensional Helmholtz equation. The formulation is based on the
nine-point fourth order compact finite difference approximation
formula. The complexity analysis of the developed scheme is also
presented. Several numerical experiments were conducted to test the
feasibility of the developed scheme. Comparisons with other existing
schemes will be reported and discussed. Preliminary results indicate
that this method is a viable alternative high accuracy solver to the
Helmholtz equation.