Abstract: This paper aims to project the construction of a
prototype azimuthal thruster, mounted with materials of low cost and
easy access, testing in a controlled environment to measure their
performance, characteristics and feasibility of future projects. The
construction of the simulation of dynamic positioning software,
responsible for simulating a vessel and reposition it when necessary.
Validation tests were performed in the form of partial or complete
system. These tests validate the system manually or automatically.
The system provides an interface to the user and simulates the
conditions unfavorable positioning of a vessel, accurately calculates
the azimuth angle, the direction of rotation of the helix and the time
that this should be turned on so that the vessel back to position
original. A serial communication connects the Simulation Dynamic
Positioning System with Embedded System causing the usergenerated
data to simulate the DP system arrives in the form of
control signals to the motors of the propellant. This article addresses
issues in the marine industry employees.
Abstract: Zn alloy and composite coatings are widely used in
buildings and structures, automobile and fasteners industries to
protect steel component from corrosion. In this paper, Zn-Ni-Al2O3
nanocomposite coatings were electrodeposited on mild steel using a
novel sol enhanced electroplating method. In this method, transparent
Al2O3 sol was added into the acidic Zn-Ni bath to produced Zn-Ni-
Al2O3 nanocomposite coatings. The effect of alumina sol on the
electrodeposition process, and coating properties was investigated
using cyclic voltammetry, XRD, ESEM and Tafel test. Results from
XRD tests showed that the structure of all coatings was single γ-
Ni5Zn21 phase. Cyclic voltammetry results showed that the
electrodeposition overpotential was lower in the presence of alumina
sol in the bath, and caused the reduction potential of Zn-Ni to shift to
more positive values. Zn-Ni-Al2O3 nanocomposite coatings produced
more uniform and compact deposits, with fine grained microstructure
when compared to Zn-Ni coatings. The corrosion resistance of Zn-Ni
coatings was improved significantly by incorporation of alumina
nanoparticles into the coatings.
Abstract: The purpose of this paper is to present a modeling and
control of a quarter-car active suspension system with unknown
mass, unknown time-delay and road disturbance. The objective of
designing the controller is to derive a control law to achieve stability
of the system and convergence that can considerably improve ride
comfort and road disturbance handling. This is accomplished by
using Routh-Hurwitz criterion based on defined parameters.
Mathematical proof is given to show the ability of the designed
controller to ensure the target of design, implementation with the
active suspension system and enhancement dispersion oscillation of
the system despite these problems. Simulations were also performed
to control quarter car suspension, where the results obtained from
these simulations verify the validity of the proposed design.
Abstract: The using of waste materials in the construction
industry can reduce the dependence on the natural aggregates which
are going at the end to deplete. The glass waste is generated in a huge
amount which can make one of its disposals in concrete industry
effective not only as a green solution but also as an advantage to
enhance the performance of mechanical properties and durability of
concrete. This article reports the performance of concrete specimens
containing different percentages of milled glass waste as a partial
replacement of cement (Powder), when they are subject to cycles of
freezing and thawing. The tests were conducted on 75-mm cubes and
75 x 75 x 300-mm prisms. Compressive strength based on laboratory
testing and non-destructive ultrasonic pulse velocity test were
performed during the action of freezing-thawing cycles (F/T). The
results revealed that the incorporation of glass waste in concrete
mixtures is not only feasible but also showed generally better strength
and durability performance than control concrete mixture. It may be
said that the recycling of waste glass in concrete mixes is not only a
disposal way, but also it can be an exploitation in concrete industry.
Abstract: This paper is focused on the reference current
calculation in the compensation mode of the active DC traction
substations. The so-called p-q theory of the instantaneous reactive
power is used as theoretical foundation. The compensation goal of
total compensation is taken into consideration for the operation under
both sinusoidal and nonsinusoidal voltage conditions, through the
two objectives of unity power factor and perfect harmonic
cancelation. Four blocks of reference current generation implement
the conceived algorithms and they are included in a specific Simulink
library, which is useful in a DSP dSPACE-based platform working
under Matlab/Simulink. The simulation results validate the
correctness of the implementation and fulfillment of the
compensation tasks.
Abstract: In this study, lipid-deprived residuals of microalgae
were hydrolyzed for the production of reducing sugars by using the
recombinant Bacillus cellulosome, carrying eight genes from the
Clostridium thermocellum ATCC27405. The obtained cellulosome
was found to exist mostly in the broth supernatant with a cellulosome
activity of 2.4 U/mL. Furthermore, the Michaelis-Menten constant
(Km) and Vmax of cellulosome were found to be 14.832 g/L and 3.522
U/mL. The activation energy of the cellulosome to hydrolyze
microalgae LDRs was calculated as 32.804 kJ/mol.
Abstract: The growth of organic farming practices in the last
few decades is continuing to stimulate the international debate about
this alternative food market. As a part of a PhD project research
about embeddedness in Alternative Food Networks (AFNs), this
paper focuses on the promotional aspects of organic farms websites
from the Madrid region. As a theoretical tool, some knowledge
categories drawn on the geographic studies literature are used to
classify the many ideas expressed in the web pages. By analysing
texts and pictures of 30 websites, the study aims to question how and
to what extent actors from organic world communicate to the
potential customers their personal beliefs about farming practices,
products qualities, and ecological and social benefits. Moreover, the
paper raises the question of whether organic farming laws and
regulations lack of completeness about the social and cultural aspects
of food.
Abstract: In this paper a novel color image compression
technique for efficient storage and delivery of data is proposed. The
proposed compression technique started by RGB to YCbCr color
transformation process. Secondly, the canny edge detection method is
used to classify the blocks into the edge and non-edge blocks. Each
color component Y, Cb, and Cr compressed by discrete cosine
transform (DCT) process, quantizing and coding step by step using
adaptive arithmetic coding. Our technique is concerned with the
compression ratio, bits per pixel and peak signal to noise ratio, and
produce better results than JPEG and more recent published schemes
(like CBDCT-CABS and MHC). The provided experimental results
illustrate the proposed technique that is efficient and feasible in terms
of compression ratio, bits per pixel and peak signal to noise ratio.
Abstract: The rapid growth of multimedia technology demands
the secure and efficient access to information. This fast growing lose
the confidence of unauthorized duplication. Henceforth the protection
of multimedia content is becoming more important. Watermarking
solves the issue of unlawful copy of advanced data. In this paper,
blind video watermarking technique has been proposed. A luminance
layer of selected frames is interlaced into two even and odd rows of
an image, further it is deinterlaced and equalizes the coefficients of
the two shares. Color watermark is split into different blocks, and the
pieces of block are concealed in one of the share under the wavelet
transform. Stack the two images into a single image by introducing
interlaced even and odd rows in the two shares. Finally, chrominance
bands are concatenated with the watermarked luminance band. The
safeguard level of the secret information is high, and it is
undetectable. Results show that the quality of the video is not
changed also yields the better PSNR values.
Abstract: Greenhouses offer us suitable conditions which can
be controlled easily for the growth of the plant and they are made by
using a covering material that allows the sun light entering into the
system. Covering material can be glass, fiber glass, plastic or another
transparent element. This study investigates the solar energy usability
rates and solar energy benefitting rates of a semi-spherical (modified
arch) type greenhouse system according to different orientations and
positions which exists under climatic conditions of Bayburt. In the
concept of this study it is tried to determine the best direction and
best sizes of a semi-spherical greenhouse to get best solar benefit
from the sun. To achieve this aim a modeling study is made by using
MATLAB. However, this modeling study is run for some determined
shapes and greenhouses it can be used for different shaped
greenhouses or buildings. The basic parameters are determined as
greenhouse azimuth angle, the rate of size of long edge to short and
seasonal solar energy gaining of greenhouse. The optimum azimuth
angles of 400, 300, 250, 200, 150, 100, 50 m2 modified arch
greenhouse are 90o, 90o, 35o, 35o, 34o, 33o and 22o while their
optimum k values (ratio of length to width) are 10, 10, 10, 10, 6, 4
and 4 respectively. Positioning the buildings in order to get more
solar heat energy in winter and less in summer brings out energy and
money savings and increases the comfort.
Abstract: This paper presents the design and fabrication of a
novel piezoelectric actuator for a gas micro pump with check valve
having the advantages of miniature size, light weight and low power
consumption. The micro pump is designed to have eight major
components, namely a stainless steel upper cover layer, a piezoelectric
actuator, a stainless steel diaphragm, a PDMS chamber layer, two
stainless steel channel layers with two valve seats, a PDMS check
valve layer with two cantilever-type check valves and an acrylic
substrate. A prototype of the gas micro pump, with a size of 52 mm ×
50 mm × 5.0 mm, is fabricated by precise manufacturing. This device
is designed to pump gases with the capability of performing the
self-priming and bubble-tolerant work mode by maximizing the stroke
volume of the membrane as well as the compression ratio via
minimization of the dead volume of the micro pump chamber and
channel. By experiment apparatus setup, we can get the real-time
values of the flow rate of micro pump and the displacement of the
piezoelectric actuator, simultaneously. The gas micro pump obtained
higher output performance under the sinusoidal waveform of 250 Vpp.
The micro pump achieved the maximum pumping rates of 1185
ml/min and back pressure of 7.14 kPa at the corresponding frequency
of 120 and 50 Hz.
Abstract: This study suggests the estimation method of stress
distribution for the beam structures based on TLS (Terrestrial Laser
Scanning). The main components of method are the creation of the
lattices of raw data from TLS to satisfy the suitable condition and
application of CSSI (Cubic Smoothing Spline Interpolation) for
estimating stress distribution. Estimation of stress distribution for the
structural member or the whole structure is one of the important
factors for safety evaluation of the structure. Existing sensors which
include ESG (Electric strain gauge) and LVDT (Linear Variable
Differential Transformer) can be categorized as contact type sensor
which should be installed on the structural members and also there are
various limitations such as the need of separate space where the
network cables are installed and the difficulty of access for sensor
installation in real buildings. To overcome these problems inherent in
the contact type sensors, TLS system of LiDAR (light detection and
ranging), which can measure the displacement of a target in a long
range without the influence of surrounding environment and also get
the whole shape of the structure, has been applied to the field of
structural health monitoring. The important characteristic of TLS
measuring is a formation of point clouds which has many points
including the local coordinate. Point clouds are not linear distribution
but dispersed shape. Thus, to analyze point clouds, the interpolation is
needed vitally. Through formation of averaged lattices and CSSI for
the raw data, the method which can estimate the displacement of
simple beam was developed. Also, the developed method can be
extended to calculate the strain and finally applicable to estimate a
stress distribution of a structural member. To verify the validity of the
method, the loading test on a simple beam was conducted and TLS
measured it. Through a comparison of the estimated stress and
reference stress, the validity of the method is confirmed.
Abstract: The main objective of this study was to assess the
seasonal variation of atmospheric polycyclic aromatic hydrocarbon
(PAH) concentrations associated with PM10 in an urban site of Győr,
Hungary. A total of 112 PM10 aerosol samples were collected in the
years of 2012 and 2013 and analyzed for PAHs by gas
chromatography method. The total PAH concentrations (sum of the
concentrations of 19 individual PAH compounds) ranged from 0.19
to 70.16 ng/m3 with the mean value of 12.29 ng/m3. Higher
concentrations of both total PAHs and benzo[a]pyrene (BaP) were
detected in samples collected in the heating seasons. Using BaPequivalent
potency index on the carcinogenic PAH concentration
data, the local population appears to be exposed to significantly
higher cancer risk in the heating seasons. However, the comparison
of the BaP and total PAH concentrations observed for Győr with
other cities it was found that the PAH levels in Győr generally
corresponded to the EU average.
Abstract: This paper concludes that, for economic development,
and to ensure survival, Kenya and similar countries must industrialize
their economy and mechanize their agriculture using modern large
scale methods.
Abstract: Since 1920, the industry has almost completely
changed the rivets production techniques for the manufacture of
permanent welding join production of structures and manufacture of
other products. The welding arc is the process more widely used in
industries. This is accomplished by the heat of an electric arc which
melts the base metal while the molten metal droplets are transferred
through the arc to the welding pool, protected from the atmosphere
by a gas curtain. The GMAW (Gas metal arc welding) process is
influenced by variables such as: current, polarity, welding speed,
electrode: extension, position, moving direction; type of joint,
welder's ability, among others. It is remarkable that the knowledge
and control of these variables are essential for obtaining satisfactory
quality welds, knowing that are interconnected so that changes in one
of them requiring changes in one or more of the other to produce the
desired results. The optimum values are affected by the type of base
metal, the electrode composition, the welding position and the quality
requirements. Thus, this paper proposes a new methodology, adding
the variable vibration through a mechanism developed for GMAW
welding, in order to improve the mechanical and metallurgical
properties which does not affect the ability of the welder and enables
repeatability of the welds made. For confirmation metallographic
analysis and mechanical tests were made.
Abstract: While choosing insulating oil, characteristic features
such as thermal cooling, endurance, efficiency and being
environment-friendly should be considered. Mineral oils are referred
as petroleum-based oil. In this study, vegetable oils investigated as an
alternative insulating liquid to mineral oil. Dissipation factor,
breakdown voltage, relative dielectric constant and resistivity
changes with the frequency and voltage of mineral, rapeseed and nut
oils were measured. Experimental studies were performed according
to ASTM D924 and IEC 60156 standards.
Abstract: Residential buildings consume significant amounts of
energy and produce large amount of emissions and waste. However,
there is a substantial potential for energy savings in this sector which
needs to be evaluated over the life cycle of residential buildings. Life
Cycle Assessment (LCA) methodology has been employed to study
the primary energy uses and associated environmental impacts of
different phases (i.e., product, construction, use, end of life, and
beyond building life) for residential buildings. Four different
alternatives of residential buildings in Vancouver (BC, Canada) with
a 50-year lifespan have been evaluated, including High Rise
Apartment (HRA), Low Rise Apartment (LRA), Single family
Attached House (SAH), and Single family Detached House (SDH).
Life cycle performance of the buildings is evaluated for embodied
energy, embodied environmental impacts, operational energy,
operational environmental impacts, total life-cycle energy, and total
life cycle environmental impacts. Estimation of operational energy
and LCA are performed using DesignBuilder software and Athena
Impact estimator software respectively.
The study results revealed that over the life span of the buildings,
the relationship between the energy use and the environmental
impacts are identical. LRA is found to be the best alternative in terms
of embodied energy use and embodied environmental impacts; while,
HRA showed the best life-cycle performance in terms of minimum
energy use and environmental impacts. Sensitivity analysis has also
been carried out to study the influence of building service lifespan
over 50, 75, and 100 years on the relative significance of embodied
energy and total life cycle energy. The life-cycle energy requirements
for SDH are found to be a significant component among the four
types of residential buildings. The overall disclose that the primary
operations of these buildings accounts for 90% of the total life cycle
energy which far outweighs minor differences in embodied effects
between the buildings.
Abstract: Brownfields are one of the most important problems
that must be solved by today's cities. The topic of this article is
description of developing a comprehensive transformation of postindustrial
area of the former iron factory national cultural heritage
lower Vítkovice. City of Ostrava used to be industrial superpower of
the Czechoslovak Republic, especially in the area of coal mining and
iron production, after declining industrial production and mining in
the 80s left many unused areas of former factories generally
brownfields and backfields. Since the late 90s we are observing how
the city officials or private entities seeking to remedy this situation.
Regeneration of brownfields is a very expensive and long-term
process. The area is now rebuilt for tourists and residents of the city
in the entertainment, cultural, and social center. It was necessary do
the reconstruction of the industrial monuments. Equally important
was the construction of new buildings, which helped reusing of the
entire complex. This is a unique example of transformation of
technical monuments and completion of necessary new objects, so
that the area could start working again and reintegrate back into the
urban system.
Abstract: In this paper, an experiment was conducted to assess
the impact of online deliberation on citizens’ attitudes. Specifically,
this research compared pre and post deliberation opinions of
participants who deliberated online via an asynchronous platform
regarding the issue of political opinion polls. Results indicate that
online deliberation had a positive effect on citizens’ attitudes since it
was found that following deliberation participants changed their
views regarding public opinion polls. Specifically, online deliberation
improved discussants perceptions regarding the reliability of polls,
while suppressing their negative views about the misuse of polls by
media, polling organizations and politicians.
Abstract: Cemented carbides, owing to their excellent
mechanical properties, have been of immense interest in the field of
hard materials for the past few decades. A number of processing
techniques have been developed to obtain high quality carbide tools,
with a wide range of grain size depending on the application and
requirements. Microwave sintering is one of the heating processes,
which has been used to prepare a wide range of materials including
ceramics. A deep understanding of microwave sintering and its
contribution towards control of grain growth and on deformation of
the resulting carbide materials requires further studies and attention.
In addition, the effect of binder materials and their behavior during
microwave sintering is another area that requires clear understanding.
This review aims to focus on microwave sintering, providing
information of how the process works and what type of materials it is
best suited for. In addition, a closer look at some microwave sintered
Tungsten Carbide-Cobalt samples will be taken and discussed,
highlighting some of the key issues and challenges faced in this
research area.