Abstract: A simple adaptive voice activity detector (VAD) is
implemented using Gabor and gammatone atomic decomposition of
speech for high Gaussian noise environments. Matching pursuit is
used for atomic decomposition, and is shown to achieve optimal
speech detection capability at high data compression rates for low
signal to noise ratios. The most active dictionary elements found by
matching pursuit are used for the signal reconstruction so that the
algorithm adapts to the individual speakers dominant time-frequency
characteristics. Speech has a high peak to average ratio enabling
matching pursuit greedy heuristic of highest inner products to isolate
high energy speech components in high noise environments. Gabor
and gammatone atoms are both investigated with identical
logarithmically spaced center frequencies, and similar bandwidths.
The algorithm performs equally well for both Gabor and gammatone
atoms with no significant statistical differences. The algorithm
achieves 70% accuracy at a 0 dB SNR, 90% accuracy at a 5 dB SNR
and 98% accuracy at a 20dB SNR using 30d B SNR as a reference
for voice activity.
Abstract: Prosperity of electronic equipment in photocopying
environment not only has improved work efficiency, but also has
changed indoor air quality. Considering the number of photocopying
employed, indoor air quality might be worse than in general office
environments. Determining the contribution from any type of
equipment to indoor air pollution is a complex matter. Non-methane
hydrocarbons are known to have an important role on air quality due
to their high reactivity. The presence of hazardous pollutants in
indoor air has been detected in one photocopying shop in Novi Sad,
Serbia. Air samples were collected and analyzed for five days, during
8-hr working time in three time intervals, whereas three different
sampling points were determined. Using multiple linear regression
model and software package STATISTICA 10 the concentrations of
occupational hazards and microclimates parameters were mutually
correlated. Based on the obtained multiple coefficients of
determination (0.3751, 0.2389 and 0.1975), a weak positive
correlation between the observed variables was determined. Small
values of parameter F indicated that there was no statistically
significant difference between the concentration levels of nonmethane
hydrocarbons and microclimates parameters. The results
showed that variable could be presented by the general regression
model: y = b0 + b1xi1+ b2xi2. Obtained regression equations allow to
measure the quantitative agreement between the variables and thus
obtain more accurate knowledge of their mutual relations.
Abstract: This article presents modeling studies of NiAl alloy
under solid-particle erosion and liquid-drop erosion. In the
solid-particle erosion simulation, attention is paid to the oxide scale
thickness variation on the alloy in high-temperature erosion
environments. The erosion damage is assumed to be deformation wear
and cutting wear mechanisms, incorporating the influence of the oxide
scale on the eroded surface; thus the instantaneous oxide thickness is
the result of synergetic effect of erosion and oxidation. For liquid-drop
erosion, special interest is in investigating the effects of drop velocity
and drop size on the damage of the target surface. The models of
impact stress wave, mean depth of penetration, and maximum depth of
erosion rate (Max DER) are employed to develop various maps for
NiAl alloy, including target thickness vs. drop size (diameter), rate of
mean depth of penetration (MDRP) vs. drop impact velocity, and
damage threshold velocity (DTV) vs. drop size.
Abstract: Wireless Sensor Networks (WSNs) have wide variety
of applications and provide limitless future potentials. Nodes in
WSNs are prone to failure due to energy depletion, hardware failure,
communication link errors, malicious attacks, and so on. Therefore,
fault tolerance is one of the critical issues in WSNs. We study how
fault tolerance is addressed in different applications of WSNs. Fault
tolerant routing is a critical task for sensor networks operating in
dynamic environments. Many routing, power management, and data
dissemination protocols have been specifically designed for WSNs
where energy awareness is an essential design issue. The focus,
however, has been given to the routing protocols which might differ
depending on the application and network architecture.
Abstract: We propose a code acquisition scheme called improved
multiple-shift (IMS) for optical code division multiple access
systems, where the optical orthogonal code is used instead of the
pseudo noise code. Although the IMS algorithm has a similar process
to that of the conventional MS algorithm, it has a better code
acquisition performance than the conventional MS algorithm. We
analyze the code acquisition performance of the IMS algorithm and
compare the code acquisition performances of the MS and the IMS
algorithms in single-user and multi-user environments.
Abstract: In this paper, we propose an automatic verification
technology of software patches for user virtual environments on IaaS
Cloud to decrease verification costs of patches. In these days, IaaS
services have been spread and many users can customize virtual
machines on IaaS Cloud like their own private servers. Regarding to
software patches of OS or middleware installed on virtual machines,
users need to adopt and verify these patches by themselves. This task
increases operation costs of users. Our proposed method replicates
user virtual environments, extracts verification test cases for user
virtual environments from test case DB, distributes patches to virtual
machines on replicated environments and conducts those test cases
automatically on replicated environments. We have implemented the
proposed method on OpenStack using Jenkins and confirmed the
feasibility. Using the implementation, we confirmed the effectiveness
of test case creation efforts by our proposed idea of 2-tier abstraction
of software functions and test cases. We also evaluated the automatic
verification performance of environment replications, test cases
extractions and test cases conductions.
Abstract: Modelling of the earth's surface and evaluation of
urban environment, with 3D models, is an important research topic.
New stereo capabilities of high resolution optical satellites images,
such as the tri-stereo mode of Pleiades, combined with new image
matching algorithms, are now available and can be applied in urban
area analysis. In addition, photogrammetry software packages gained
new, more efficient matching algorithms, such as SGM, as well as
improved filters to deal with shadow areas, can achieve more dense
and more precise results.
This paper describes a comparison between 3D data extracted
from tri-stereo and dual stereo satellite images, combined with pixel
based matching and Wallis filter. The aim was to improve the
accuracy of 3D models especially in urban areas, in order to assess if
satellite images are appropriate for a rapid evaluation of urban
environments.
The results showed that 3D models achieved by Pleiades tri-stereo
outperformed, both in terms of accuracy and detail, the result
obtained from a Geo-eye pair. The assessment was made with
reference digital surface models derived from high resolution aerial
photography. This could mean that tri-stereo images can be
successfully used for the proposed urban change analyses.
Abstract: In this paper a real-time obstacle avoidance approach
for both autonomous and non-autonomous dynamical systems (DS) is
presented. In this approach the original dynamics of the controller
which allow us to determine safety margin can be modulated.
Different common types of DS increase the robot’s reactiveness in
the face of uncertainty in the localization of the obstacle especially
when robot moves very fast in changeable complex environments.
The method is validated by simulation and influence of different
autonomous and non-autonomous DS such as important
characteristics of limit cycles and unstable DS. Furthermore, the
position of different obstacles in complex environment is explained.
Finally, the verification of avoidance trajectories is described through
different parameters such as safety factor.
Abstract: Corrosion inhibitors are widely used in concrete
industry to reduce the corrosion rate of steel rebar which is present in
contact with aggressive environments. The present work aims to
using Zamzam water from well located within the Masjid al-Haram
in Mecca, Saudi Arabia 20 m (66 ft) east of the Kaaba, the holiest
place in Islam as corrosion inhibitor for steel in rain water and
simulated acid rain. The effect of Zamzam water was investigated by
electrochemical impedance spectroscopy (EIS) and Potentiodynamic
polarization techniques in Department of Civil Engineering - IUT
Saint-Nazaire, Nantes University, France. Zamzam water is
considered to be one of the most important steel corrosion inhibitor
which is frequently used in different industrial applications. Results
showed that zamzam water gave a very good inhibition for steel
corrosion in rain water and simulated acid rain.
Abstract: The purpose of this study is to compare Self
Compacting Concrete (SCC) and Conventional Concrete (CC) in
terms of their capillary water absorption. During the comparison of
SCC and CC, the effects of two different factors were also
investigated: concrete strength class and curing condition. In the
study, both SCC and CC were produced in three different concrete
classes (C25, C50 and C70) and the other parameter (i.e. curing
condition) was determined as two levels: moisture and air curing. It
was observed that, for both curing environments and all strength
classes of concrete, SCCs had lower capillary water absorption values
than that of CCs. It was also detected that, for both SCC and CC,
capillary water absorption values of samples kept in moisture curing
were significantly lower than that of samples stored in air curing.
Additionally, it was determined that capillary water absorption values
for both SCC and CC decrease with increasing strength class of
concrete for both curing environments.
Abstract: Domestic goats (Capra hircus) are extremely diverse
species and principal animal genetic resource of the developing
world. These facilitate a persistent supply of meat, milk, fibre, and
skin and are considered as important revenue generators in small
pastoral environments. This study aimed to fingerprint β-LG gene at
PCR-RFLP level in native Saudi goat breeds (Ardi, Habsi and Harri)
in an attempt to have a preliminary image of β-LG genotypic patterns
in Saudi breeds as compared to other foreign breeds such as Indian
and Egyptian. Also, the Phylogenetic analysis was done to investigate
evolutionary trends and similarities among the caprine β-LG gene
with that of the other domestic specie, viz. cow, buffalo and sheep.
Blood samples were collected from 300 animals (100 for each breed)
and genomic DNA was extracted. A fragment of the β-LG gene
(427bp) was amplified using specific primers. Subsequent digestion
with Sac II restriction endonuclease revealed two alleles (A and B)
and three different banding patterns or genotypes i.e. AA, AB and
BB. The statistical analysis showed a general trend that β-LG AA
genotype had higher milk yield than β-LG AB and β-LG BB
genotypes. Nucleotide sequencing of the selected β-LG fragments
was done and submitted to GenBank NCBI (Accession No.
KJ544248, KJ588275, KJ588276, KJ783455, KJ783456 and
KJ874959). Phylogenetic analysis on the basis of nucleotide
sequences of native Saudi goats indicated evolutional similarity with
the GenBank reference sequences of goat, Bubalus bubalis and Bos
taurus. However, the origin of sheep which is the most closely
related from the evolutionary point of view, was located some
distance away.
Abstract: The bean (Phaseolus vulgaris L.) is one of the best
known of the legumes, and it has a long cultivation tradition in Italy.
The territory of “Subappennino Dauno” (southern Italy) is at around
700 m a.s.l. and is predominantly grown with cereals, olive trees and
grapevines. Ecotypes of white beans to eat dry (such as cannellini
beans) are also grown, which are sought for their palatability, high
digestibility, and ease of cooking. However, these are not easy to find
on the market due to their low production in relatively small areas
and on small family farms that use seeds handed down from
generation to generation. The introduction of these ecotypes in plain
areas of the Puglia region would provide an opportunity to promote
the diffusion of this type of bean. To investigate the adaptability of
these ecotypes in plain environments (Cerignola, in southern Italy) a
comparative trial was carried out between three ‘Monti Dauni’
ecotypes (E1, E2, E3) that are native to mountain areas and the
similar commercial variety, ‘Cannellini’. The data provide useful
information about the quantitative and qualitative characteristics of
these ecotypes when grown in lowland environments. Ecotype E3
provided the greatest bean production (2.34 t ha-1) compared to
‘Cannellini’ (1.28 t ha-1) and the other ecotypes (0.55 and 0.40 t ha-1,
for E1 and E2, respectively), due to its greater plant growth and the
larger size of the seed (and thickness, in particular). Finally, ecotype
E2 provided the greatest protein content (31.2%), although not
significantly different from the commercial cultivar ‘Cannellini’
(32.1%).
Abstract: In this study, we aim to demonstrate a microgrid
system experimental simulation for an easy understanding of a
large-scale microgrid system. This model is required for industrial
training and learning environments. However, in order to create an
exact representation of a microgrid system, the laboratory-scale
system must fulfill the requirements of a grid-connected inverter, in
which power values are assigned to the system to cope with the
intermittent output from renewable energy sources. Aside from that,
during fluctuations in load capacity, the grid-connected system must
be able to supply power from the utility grid side and microgrid side in
a balanced manner. Therefore, droop control is installed in the
inverter’s control board to maintain a balanced power sharing in both
sides. This power control in a stand-alone condition and droop control
in a grid-connected condition must be implemented in order to
maintain a stabilized system. Based on the experimental results, power
control and droop control can both be applied in the system by
comparing the experimental and reference values.
Abstract: The organizations of European and Czech critical
infrastructure have specific position, mission, characteristics and
behaviour in European Union and Czech state/business environments,
regarding specific requirements for regional and global security
environments. They must respect policy of national security and
global rules, requirements and standards in all their inherent and
outer processes of supply - customer chains and networks. A
controlling is generalized capability to have control over situational
policy. This paper aims and purposes are to introduce the controlling
as quite new necessary process attribute providing for critical
infrastructure is environment the capability and profit to achieve its
commitment regarding to the effectiveness of the quality
management system in meeting customer/ user requirements and also
the continual improvement of critical infrastructure organization’s
processes overall performance and efficiency, as well as its societal
security via continual planning improvement via DYVELOP
modelling.
Abstract: Al-Si-Mg-Ni(-Cu) alloys are widely used in the automotive industry. They have the advantage of low weight associated with low coefficient of thermal expansion and excellent mechanical properties – mainly at high temperatures. The corrosion resistance of these alloys in coastal area, particularly sea water, however is not yet known. In this investigation, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization have been used to evaluate the corrosion resistance of Al-6Si-0.5Mg-2Ni (-2Cu) alloys in simulated sea water environments. The potentiodynamic polarization curves reveal that 2 wt% Cu content alloy (Alloy-2) is more prone to corrosion than the Cu free alloy (Alloy-1). But the EIS test results showed that corrosion resistance or charge transfer resistance (Rct) increases with the addition of Cu. Due to addition of Cu and thermal treatment, the magnitude of open circuit potential (OCP), corrosion potential (Ecorr) and pitting corrosion potential (Epit) of Al-6Si-0.5Mg-2Ni alloy in NaCl solution were shifted to the more noble direction.
Abstract: Sustainable tall buildings that provide comfortable,
healthy and efficient indoor environments are clearly desirable as the
densification of living and working space for the world’s increasing
population proceeds. For environmental concerns, these buildings
must also be energy efficient. One component of these tasks is the
provision of indoor air quality and thermal comfort, which can be
enhanced with natural ventilation by the supply of fresh air. Working
spaces can only be naturally ventilated with connections to the
outdoors utilizing operable windows, double facades, ventilation
stacks, balconies, patios, terraces and skygardens. Large amounts of
fresh air can be provided to the indoor spaces without mechanical
air-conditioning systems, which are widely employed in
contemporary tall buildings.
This paper tends to present the concept of natural ventilation for
sustainable tall office buildings in order to achieve healthy and
comfortable working spaces, as well as energy efficient
environments. Initially the historical evolution of ventilation
strategies for tall buildings is presented, beginning with natural
ventilation and continuing with the introduction of mechanical airconditioning
systems. Then the emergence of natural ventilation due
to the health and environmental concerns in tall buildings is handled,
and the strategies for implementing this strategy are revealed. In the
next section, a number of case studies that utilize this strategy are
investigated. Finally, how tall office buildings can benefit from this
strategy is discussed.
Abstract: In this paper, we propose a method that allows faster and more accurate detection of traffic lights by a vision sensor during driving, DGPS is used to obtain physical location of a traffic light, extract from the image information of the vision sensor only the traffic light area at this location and ascertain if the sign is in operation and determine its form. This method can solve the problem in existing research where low visibility at night or reflection under bright light makes it difficult to recognize the form of traffic light, thus making driving unstable. We compared our success rate of traffic light recognition in day and night road environments. Compared to previous researches, it showed similar performance during the day but 50% improvement at night.
Abstract: Lately, with the increasing number of location-based applications, demand for highly accurate and reliable indoor localization became urgent. This is a challenging problem, due to the measurement variance which is the consequence of various factors like obstacles, equipment properties and environmental changes in complex nature of indoor environments. In this paper we propose low-cost custom-setup infrastructure solution and localization algorithm based on the Weighted Centroid Localization (WCL) method. Localization accuracy is increased by several enhancements: calibration of RSSI values gained from wireless nodes, repetitive measurements of RSSI to exclude deviating values from the position estimation, and by considering orientation of the device according to the wireless nodes. We conducted several experiments to evaluate the proposed algorithm. High accuracy of ~1m was achieved.
Abstract: The rapid expansion of deserts in recent decades as a result of human actions combined with climatic changes has highlighted the necessity to understand biological processes in arid environments. Whereas physical processes and the biology of flora and fauna have been relatively well studied in marginally used arid areas, knowledge of desert soil micro-organisms remains fragmentary. The objective of this study is to conduct a diversity analysis of bacterial communities in unvegetated arid soils. Several biological phenomena in hot deserts related to microbial populations and the potential use of micro-organisms for restoring hot desert environments. Dry land ecosystems have a highly heterogeneous distribution of resources, with greater nutrient concentrations and microbial densities occurring in vegetated than in bare soils. In this work, we found it useful to use techniques of artificial intelligence in their treatment especially artificial neural networks (ANN). The use of the ANN model, demonstrate his capability for addressing the complex problems of uncertainty data.
Abstract: The paper presents actual benefits and drawbacks of a multidirectional autonomous hovercraft conceived with limited resources and designed for indoor exploration. Recent developments in the field have led to the apparition of very powerful automotive systems capable of very high calculation and exploration in complex unknown environments. They usually propose very complex algorithms, high precision/cost sensors and sometimes have heavy calculation consumption with complex data fusion. These systems are usually powerful but have a certain price, and the benefits may not be worth the cost, especially considering their hardware limitations and their power consumption. The present approach is to build a compromise between cost, power consumption and results preciseness.