Abstract: In this paper, the problem of fault detection and
isolation in the attitude control subsystem of spacecraft formation
flying is considered. In order to design the fault detection method, an
extended Kalman filter is utilized which is a nonlinear stochastic state
estimation method. Three fault detection architectures, namely,
centralized, decentralized, and semi-decentralized are designed based
on the extended Kalman filters. Moreover, the residual generation
and threshold selection techniques are proposed for these
architectures.
Abstract: Over the past four decades, the fatigue behavior of
nickel-based alloys has been widely studied. However, in recent
years, significant advances in the fabrication process leading to grain
size reduction have been made in order to improve fatigue properties
of aircraft turbine discs. Indeed, a change in particle size affects the
initiation mode of fatigue cracks as well as the fatigue life of the
material. The present study aims to investigate the fatigue behavior of
a newly developed nickel-based superalloy under biaxial-planar
loading. Low Cycle Fatigue (LCF) tests are performed at different
stress ratios so as to study the influence of the multiaxial stress state
on the fatigue life of the material. Full-field displacement and strain
measurements as well as crack initiation detection are obtained using
Digital Image Correlation (DIC) techniques. The aim of this
presentation is first to provide an in-depth description of both the
experimental set-up and protocol: the multiaxial testing machine, the
specific design of the cruciform specimen and performances of the
DIC code are introduced. Second, results for sixteen specimens
related to different load ratios are presented. Crack detection, strain
amplitude and number of cycles to crack initiation vs. triaxial stress
ratio for each loading case are given. Third, from fractographic
investigations by scanning electron microscopy it is found that the
mechanism of fatigue crack initiation does not depend on the triaxial
stress ratio and that most fatigue cracks initiate from subsurface
carbides.
Abstract: The thermal behavior of a large-scale, phase change material (PCM) enhanced building envelope system was studied in regard to the need for pre-fabricated construction in subtropical regions. The proposed large-scale envelope consists of a reinforced aluminum skin, insulation core, phase change material and reinforced gypsum board. The PCM impact on an energy efficiency of an enveloped room was resolved by validation of the EnergyPlus numerical scheme and optimization of a smart material location in the core. The PCM location was optimized by a minimization method of a cooling energy demand. It has been shown that there is good agreement between the test and simulation results. The optimal location of the PCM layer in Hong Kong summer conditions has been then recomputed for core thicknesses of 40, 60 and 80 mm. A non-dimensional value of the optimal PCM location was obtained to be same for all the studied cases and the considered external and internal conditions.
Abstract: The development of allometric models is crucial to
accurate forest biomass/carbon stock assessment. The aim of this
study was to develop a set of biomass prediction models that will
enable the determination of total tree aboveground biomass for
savannah woodland area in Niger State, Nigeria. Based on the data
collected through biometric measurements of 1816 trees and
destructive sampling of 36 trees, five species specific and one site
specific models were developed. The sample size was distributed
equally between the five most dominant species in the study site
(Vitellaria paradoxa, Irvingia gabonensis, Parkia biglobosa,
Anogeissus leiocarpus, Pterocarpus erinaceous). Firstly, the
equations were developed for five individual species. Secondly these
five species were mixed and were used to develop an allometric
equation of mixed species. Overall, there was a strong positive
relationship between total tree biomass and the stem diameter. The
coefficient of determination (R2 values) ranging from 0.93 to 0.99 P
< 0.001 were realised for the models; with considerable low standard
error of the estimates (SEE) which confirms that the total tree above
ground biomass has a significant relationship with the dbh. F-test
values for the biomass prediction models were also significant at p
Abstract: Robotic surgery is used to enhance minimally invasive
surgical procedure. It provides greater degree of freedom for surgical
tools but lacks of haptic feedback system to provide sense of touch to
the surgeon. Surgical robots work on master-slave operation, where
user is a master and robotic arms are the slaves. Current, surgical
robots provide precise control of the surgical tools, but heavily rely
on visual feedback, which sometimes cause damage to the inner
organs. The goal of this research was to design and develop a realtime
Simulink based robotic system to study force feedback
mechanism during instrument-object interaction. Setup includes three
VelmexXSlide assembly (XYZ Stage) for three dimensional
movement, an end effector assembly for forceps, electronic circuit for
four strain gages, two Novint Falcon 3D gaming controllers,
microcontroller board with linear actuators, MATLAB and Simulink
toolboxes. Strain gages were calibrated using Imada Digital Force
Gauge device and tested with a hard-core wire to measure
instrument-object interaction in the range of 0-35N. Designed
Simulink model successfully acquires 3D coordinates from two
Novint Falcon controllers and transfer coordinates to the XYZ stage
and forceps. Simulink model also reads strain gages signal through
10-bit analog to digital converter resolution of a microcontroller
assembly in real time, converts voltage into force and feedback the
output signals to the Novint Falcon controller for force feedback
mechanism. Experimental setup allows user to change forward
kinematics algorithms to achieve the best-desired movement of the
XYZ stage and forceps. This project combines haptic technology
with surgical robot to provide sense of touch to the user controlling
forceps through machine-computer interface.
Abstract: The detection of moving objects from a video image
sequences is very important for object tracking, activity recognition,
and behavior understanding in video surveillance.
The most used approach for moving objects detection / tracking is
background subtraction algorithms. Many approaches have been
suggested for background subtraction. But, these are illumination
change sensitive and the solutions proposed to bypass this problem
are time consuming.
In this paper, we propose a robust yet computationally efficient
background subtraction approach and, mainly, focus on the ability to
detect moving objects on dynamic scenes, for possible applications in
complex and restricted access areas monitoring, where moving and
motionless persons must be reliably detected. It consists of three
main phases, establishing illumination changes invariance,
background/foreground modeling and morphological analysis for
noise removing.
We handle illumination changes using Contrast Limited Histogram
Equalization (CLAHE), which limits the intensity of each pixel to
user determined maximum. Thus, it mitigates the degradation due to
scene illumination changes and improves the visibility of the video
signal. Initially, the background and foreground images are extracted
from the video sequence. Then, the background and foreground
images are separately enhanced by applying CLAHE.
In order to form multi-modal backgrounds we model each channel
of a pixel as a mixture of K Gaussians (K=5) using Gaussian Mixture
Model (GMM). Finally, we post process the resulting binary
foreground mask using morphological erosion and dilation
transformations to remove possible noise.
For experimental test, we used a standard dataset to challenge the
efficiency and accuracy of the proposed method on a diverse set of
dynamic scenes.
Abstract: MSMEs are regarded as the sunrise sector of the
Indian economy in view of its large potential for growth and likely
socio economic impact specifically on employment and income
generation. In today’s competitive business environment, global
competition forces companies to continuously seek ways of
improving their products and services. The pressure on organizations
to adapt to new technologies and external threats requires
resourcefulness, creativity and innovation. Market has become more
open, competitive and customers more demanding. Without
continuous technology innovation, no organization can ever remain
competitive. Innovations reflect a critical way in which organizations
respond to either technological or market challenges. The need of the
market is to deliver high quality products through continuous
changing in features in product, improve existing products, reduce
their cost, and improve employee skills, training, technology
infrastructure and financial policies. Therefore, the key factor of
organization’s ability to change is innovation. The study presents a
detailed review of literature on the role of technology innovation in
improving manufacturing performance of industries.
Abstract: Since the initial creation of the Barbie doll in 1959, it
became a symbol of US society. Likewise, the Licca-chan, a Japanese
doll created in 1967, also became a Japanese symbolic doll of Japanese
society. Prior to the introduction of Licca-chan, Barbie was already
marketed in Japan but their sales were dismal. Licca-chan (an actual
name: Kayama Licca) is a plastic doll with a variety of sizes ranging
from 21.0 cm to 29.0 cm which many Japanese girls dream of having.
For over 35 years, the manufacturer, Takara Co., Ltd. has sold over 48
million dolls and has produced doll houses, accessories, clothes, and
Licca-chan video games for the Nintendo DS. Many First-generation
Licca-chan consumers still are enamored with Licca-chan, and go to
Licca-chan House, in an amusement park with their daughters. These
people are called Licca-chan maniacs, as they enjoy touring the
Licca-chan’s factory in Tohoku or purchase various Licca-chan
accessories. After the successful launch of Licca-chan into the
Japanese market, a mixed-like doll from the US and Japan, a doll,
JeNny, was later sold in the same Japanese market by Takara Co., Ltd.
in 1982.
Comparison of these cultural iconic dolls, Barbie and Licca-chan,
are analyzed in this paper. In fact, these dolls have concepts of girls’
dreams. By using concepts of mythology of Jean Baudrillard, these
dolls can be represented idealized images of figures in the products for
consumers, but at the same time, consumers can see products with
different perspectives, which can cause controversy.
Abstract: Fungal mutant strains have produced cellulase and
xylanase enzymes, and have induced high hydrolysis with enhanced
of rice straw. The mutants were obtained by exposing Penicillium
strain to UV-light treatments. Screening and selection after treatment
with UV-light were carried out using cellulolytic and xylanolytic
clear zones method to select the hypercellulolytic and
hyperxylanolytic mutants. These mutants were evaluated for their
cellulase and xylanase enzyme production as well as their abilities for
biodegradation of rice straw. The mutant 12 UV/1 produced 306.21%
and 209.91% cellulase and xylanase, respectively, as compared with
the original wild type strain. This mutant showed high capacity of
rice straw degradation. The effectiveness of tested mutant strain and
that of wild strain was compared in relation to enhancing the
composting process of rice straw and animal manures mixture. The
results obtained showed that the compost product of inoculated
mixture with mutant strain (12 UV/1) was the best compared to the
wild strain and un-inoculated mixture. Analysis of the composted
materials showed that the characteristics of the produced compost
were close to those of the high quality standard compost. The results
obtained in the present work suggest that the combination between
rice straw and animal manure could be used for enhancing the
composting process of rice straw and particularly when applied with
fungal decomposer accelerating the composting process.
Abstract: Previous studies on financial distress prediction choose
the conventional failing and non-failing dichotomy; however, the
distressed extent differs substantially among different financial
distress events. To solve the problem, “non-distressed”, “slightlydistressed”
and “reorganization and bankruptcy” are used in our article
to approximate the continuum of corporate financial health. This paper
explains different financial distress events using the two-stage method.
First, this investigation adopts firm-specific financial ratios, corporate
governance and market factors to measure the probability of various
financial distress events based on multinomial logit models.
Specifically, the bootstrapping simulation is performed to examine the
difference of estimated misclassifying cost (EMC). Second, this work
further applies macroeconomic factors to establish the credit cycle
index and determines the distressed cut-off indicator of the two-stage
models using such index. Two different models, one-stage and
two-stage prediction models are developed to forecast financial
distress, and the results acquired from different models are compared
with each other, and with the collected data. The findings show that the
one-stage model has the lower misclassification error rate than the
two-stage model. The one-stage model is more accurate than the
two-stage model.
Abstract: Power systems are operating under stressed condition
due to continuous increase in demand of load. This can lead to
voltage instability problem when face additional load increase or
contingency. In order to avoid voltage instability suitable size of
reactive power compensation at optimal location in the system is
required which improves the load margin. This work aims at
obtaining optimal size as well as location of compensation in the 39-
bus New England system with the help of Bacteria Foraging and
Genetic algorithms. To reduce the computational time the work
identifies weak candidate buses in the system, and then picks only
two of them to take part in the optimization. The objective function is
based on a recently proposed voltage stability index which takes into
account the weighted average sensitivity index is a simpler and faster
approach than the conventional CPF algorithm. BFOA has been
found to give better results compared to GA.
Abstract: Skin aging is a slow multifactorial process influenced
by both internal as well as external factors. Ultra-violet radiations
(UV), diet, smoking and personal habits are the most common
environmental factors that affect skin aging. Fat contents and fibrous
proteins as collagen and elastin are core internal structural
components. The direct influence of UV on elastin integrity and
health is central on aging of skin especially by time. The deposition
of abnormal elastic material is a major marker in a photo-aged skin.
Searching for compounds that may protect against cutaneous photodamage
is exceedingly valued. Retinoids and alpha hydroxy acids
have been endorsed by some researchers as possible candidates for
protecting and or repairing the effect of UV damaged skin. For
consolidating a better system of anti- and protective effects of such
anti-aging agents, we evaluated the combinatory effects of various
dosages of lactic acid and retinol on the dermal fibroblast’s elastin
levels exposed to UV. The UV exposed cells showed significant
reduction in the elastin levels. A combination of drugs with a higher
concentration of lactic acid (30 -35 mM) and a lower concentration of
retinol (10-15mg/mL) showed to work better in maintaining elastin
concentration in UV exposed cells. We assume this preservation
could be the result of increased tropo-elastin gene expression
stimulated by retinol whereas lactic acid probably repaired the UV
irradiated damage by enhancing the amount and integrity of the
elastin fibers.
Abstract: Humans are social mammals, of the primate order.
Our biology, our behaviour and our pathologies are unique to us. In
our desire to understand, reduce solitary confinement one source of
information is the many reports of social isolation of other social
mammals, especially primates. A behavioural study was conducted in
the department of pharmacology at Indira Gandhi Medical College,
Shimla in Himachalpradesh province in India using white albino
mice. Different behavioural parameters were observed by using open
field, tail suspension, tests for aggressive behaviour and social
interactions and the effect of isolation was studied. The results were
evaluated and the standard statistics were applied. The said study was
done to establish facts that isolation itself impairs social behaviour
and can lead to alcohol dependence as well as related drug
dependence.
Abstract: A well designed and executed Production Planning
and Control (PPC) system is one of the key levers for superior
performance in the current manufacturing set-up. Hence, measuring
the PPC system performance has become a necessity for long term
success. The present study examined PPC related issues which
impact the production capacity and productivity of leather companies
with special focus on Kombolcha Tannery Share Company (KTSC),
Ethiopia. Physical observation, interview, and questionnaire were
used to generate necessary information from the respondents and
reach valid conclusions. Company annual reports were referred and
analyzed to triangulate primary data. Consequently, the study
revealed that KTSC runs below its capacity due to its inefficient PPC
system being in use for which the root causes were identified. The
study thereby conceptualizes a PPC system improvement framework
comprising three pillars viz., management culture, internal capability
and performance measurement together with key considerations in
each case. The study findings enable the company to recognize the
importance of efficient PPC system as a source of competitive
advantage. It also aid managers in evaluating various PPC execution
schemes to enhance productivity.
Abstract: Poly vinyl acetate (PVA)-based titania (TiO2)–carbon
nanotube composite nanofibers (PVA-TCCNs) with various
PVA-to-solvent ratios and PVA-based TiO2 composite nanofibers
(PVA-TN) were synthesized using an electrospinning process,
followed by thermal treatment. The photocatalytic activities of these
nanofibers in the degradation of airborne monocyclic aromatics under
visible-light irradiation were examined. This study focuses on the
application of these photocatalysts to the degradation of the target
compounds at sub-part-per-million indoor air concentrations. The
characteristics of the photocatalysts were examined using scanning
electron microscopy, X-ray diffraction, ultraviolet-visible
spectroscopy, and Fourier-transform infrared spectroscopy. For all the
target compounds, the PVA-TCCNs showed photocatalytic
degradation efficiencies superior to those of the reference PVA-TN.
Specifically, the average photocatalytic degradation efficiencies for
benzene, toluene, ethyl benzene, and o-xylene (BTEX) obtained using
the PVA-TCCNs with a PVA-to-solvent ratio of 0.3 (PVA-TCCN-0.3)
were 11%, 59%, 89%, and 92%, respectively, whereas those observed
using PVA-TNs were 5%, 9%, 28%, and 32%, respectively.
PVA-TCCN-0.3 displayed the highest photocatalytic degradation
efficiency for BTEX, suggesting the presence of an optimal
PVA-to-solvent ratio for the synthesis of PVA-TCCNs. The average
photocatalytic efficiencies for BTEX decreased from 11% to 4%, 59%
to 18%, 89% to 37%, and 92% to 53%, respectively, when the flow
rate was increased from 1.0 to 4.0 L min1. In addition, the average
photocatalytic efficiencies for BTEX increased 11% to ~0%, 59% to
3%, 89% to 7%, and 92% to 13%, respectively, when the input
concentration increased from 0.1 to 1.0 ppm. The prepared
PVA-TCCNs were effective for the purification of airborne aromatics
at indoor concentration levels, particularly when the operating
conditions were optimized.
Abstract: This paper presents two techniques, local feature
extraction using image spectrum and low frequency spectrum
modelling using GMM to capture the underlying statistical
information to improve the performance of face recognition
system. Local spectrum features are extracted using overlap sub
block window that are mapped on the face image. For each of this
block, spatial domain is transformed to frequency domain using
DFT. A low frequency coefficient is preserved by discarding high
frequency coefficients by applying rectangular mask on the
spectrum of the facial image. Low frequency information is non-
Gaussian in the feature space and by using combination of several
Gaussian functions that has different statistical properties, the best
feature representation can be modelled using probability density
function. The recognition process is performed using maximum
likelihood value computed using pre-calculated GMM components.
The method is tested using FERET datasets and is able to achieved
92% recognition rates.
Abstract: Pedagogy has always been open to other disciplines
that reflect about the educational process (philosophy, sociology,
psychology, anthropology, technology, etc.). Its interdisciplinary
openness puts education, as the subject of pedagogy within a broader
context of the community, enabling the knowledge of other
disciplines to contribute to a better understanding of the fundamental
pedagogical notion of education. The purpose of pedagogy as a
science serves humans, strives towards humans, must be for humans,
and this is its ultimate goal. Humans are essentially dependent on
education, which is also considered as a category of humans’ being,
because through education an entire world develops in humans.
Anthropological assumptions of humans as "deficient beings" see the
solution in education, but they also indicate a wealth of shortcomings,
because they provide an opportunity for enrichment and formation of
culture, living and the self. In that context, this paper illustrates the
determination of pedagogy through an anthropological conception of
humans and the phenomenon of education. It presents a review of
anthropological ideas about education, by providing an analysis of
relevant literature dealing with the anthropological notion of humans,
which provides fruitful conditions for a pedagogical reconsideration
of education.
Abstract: Co metal supported on SiO2 and Al2O3 catalysts with
a metal loading varied from 30 of 70 wt.% were evaluated for
decomposition of methane to COx free hydrogen and carbon
nanomaterials. The catalytic runs were carried out from 550-800oC
under atmospheric pressure using fixed bed vertical flow reactor. The
fresh and spent catalysts were characterized by BET surface area
analyzer, XRD, SEM, TEM and TG analysis. The data showed that
50% Co/Al2O3 catalyst exhibited remarkable higher activity at 800oC
with respect to H2 production compared to rest of the catalysts.
However, the catalytic activity and durability was greatly declined at
higher temperature. The main reason for the catalytic inhibition of Co
containing SiO2 catalysts is the higher reduction temperature of
Co2SiO4. TEM images illustrate that the carbon materials with
various morphologies, carbon nanofibers (CNFs), helical-shaped
CNFs and branched CNFs depending on the catalyst composition and
reaction temperature were obtained.
Abstract: Emissions of atmospheric pollutants from ships and
harbour activities are a growing concern at international level given
their potential impacts on air quality and climate. These close-to-land
emissions have potential impact on local communities in terms of air
quality and health. Recent studies show that the impact of maritime
traffic to atmospheric particulate matter concentrations in several
coastal urban areas is comparable with the impact of road traffic of a
medium size town. However, several different approaches have been
used for these estimates making difficult a direct comparison of
results. In this work, an integrated approach based on emission
inventories and dedicated measurement campaigns has been applied
to give a comparable estimate of the impact of maritime traffic to
PM2.5 and particle number concentrations in three major harbours of
the Adriatic/Ionian Seas. The influences of local meteorology and of
the logistic layout of the harbours are discussed.
Abstract: This article deals with geographical conditions in
terrain and their effect on the movement of vehicles, their effect on
speed and safety of movement of people and vehicles. Finding of the
optimal routes outside the communication is studied in the Army
environment, but it occur in civilian as well, primarily in crisis
situation, or by the provision of assistance when natural disasters
such as floods, fires, storms etc., have happened. These movements
require the optimization of routes when effects of geographical
factors should be included. The most important factor is the surface
of a terrain. It is based on several geographical factors as are slopes,
soil conditions, micro-relief, a type of surface and meteorological
conditions. Their mutual impact has been given by coefficient of
deceleration. This coefficient can be used for the commander`s
decision. New approaches and methods of terrain testing,
mathematical computing, mathematical statistics or cartometric
investigation are necessary parts of this evaluation.