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ARPN Journal of Engineering and
Applied Sciences
June 2020 | Vol. 15 No. 11 |
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Title: |
Influence of abrasive wheels characteristics on phases change of nitinol
in different structural conditions |
Author (s): |
Soler Y. I. and Kazimirov D. Yu. |
Abstract: |
The aim of this work is to evaluate changes of nitinol structure in the
condition of austenite and martensite during grinding of surfaces.
Different abrasive wheels and constant grinding mode were used in the
experiment. The composition of nitinol was studied by x-ray phase
analysis. It was found that the grinding of nitinol, when it is in
austenite state better retains phase fraction than in martensite state.
Grinding leads to secondary intermetallic compounds formation, as well
as basic phases decrease as compared with the parent state. Abrasive
wheel characteristics have a noticeable but not unambiguous effect on
the stability of the phases. NiTi phases’ content boundaries, as well as
their absolute change after grinding have been determined. |
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Title: |
Performance of geopolymer bricks with various
NaOH concentrations as
activator |
Author (s): |
Si-Huy Ngo |
Abstract: |
This study investigated the performance of geopolymer bricks that were
produced using fly ash, chippings and sodium hydroxide (NaOH) solution.
Brick mixtures were designed with solution-to-binder ratio of 0.35. The
NaOH solutions of 5, 8, 10 and 12 M were used as alkaline activators.
The effect of NaOH concentration on properties of geopolymer bricks,
including compressive strength, ultrasonic pulse velocity, thermal
conductivity, and electrical resistance was investigated. In addition,
the scanning electron microscope (SEM) was also used to observe the
microstructure of geopolymer bricks. Test results indicated that the
compressive strength, ultrasonic pulse velocity, thermal conductivity,
and electrical resistance of geopolymer bricks increased with increasing
NaOH concentration. Furthermore, SEM micrographs showed a higher hydrate
rate of fly ash in brick samples with higher NaOH concentration. All
brick samples investigated in this study exhibited a good quality with
compressive strength of above 10 MPa, ultrasonic pulse velocity of above
2500 m/s, and electrical resistance of above 2 k?-cm. |
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Title: |
Design and implementation of a virtual and remote laboratory to control
a speed plant |
Author (s): |
Faiber Robayo Betancourt, Jonatan Legro Pastrana and Camilo Andrés Muñoz |
Abstract: |
This paper presents the design and implementation of a virtual and
remote laboratory created for controlling a speed plant located in the
control laboratory at Surcolombiana University. The aim purpose is that
the student has the first contact with the plant (virtually) before
working with the physical one, understands its operation, restrictions
and prevents any damage to the same equipment. Students can handle the
actual plant remotely by another application created for this purpose,
enabling it to take data that later will serve for the identification,
processing and implementation controllers designed to meet the desired
specifications. Also, it has an IP camera to visualize and understand
the effects of its running. The project is based on the Easy Java
Simulations software (EJS), responsible for all the interactive and
visual interface part, linked to the Matlab software. Performance
validation of the generic controller was carried using Matlab tools,
achieving great results, confirming the reliability of the applications
created. |
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Title: |
Conception and hardware minimization of a new chien search block for
Reed Solomon Codes with implementation on FPGA card |
Author (s): |
Mohamed Elghayyaty, Azeddine Wahbi, Anas El Habti El Idrissi, Omar
Mouhib, Laamari Hlou and Abdelkader Hadjoudja |
Abstract: |
Error Correcting Codes such as Reed Solomon (RS) and Bose, Chaudhuri,
and Hocquenghem (BCH) are widely used in communication and storage
systems in order to correct and control errors introduced by
transmission channel. In this paper, a simplified algorithm for RS and
BCH decoding is proposed with a view to reduce the number of components
compared to the basic chien search block. First, we developed the design
of the proposed algorithm second, we generated and simulated the
hardware description language source code using Quartus software tools
and finally we implemented the new algorithm of chien search block on
FPGA card. |
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Title: |
Characterization of trilinear flow regime in fractal shale reservoirs |
Author (s): |
Freddy H. Escobar, Ruthsandy Barón-Morela and Daniel Suescún-Díaz |
Abstract: |
This paper presents the analysis of pressure tests in unconventional
reservoirs from the trilinear model of anomalous diffusion based on
fractal geometry and anomalous diffusion in order to simulate the
heterogeneity of flow in the reservoir in order to be able to obtain a
flow prediction approximate to the real. Based on this model, we
generate curves in which by applying the TDS methodology, new equations
to determine reservoir parameters such as internal reservoir
permeability, hydraulic fracture permeability, fracture conductivity,
and reservoir dimensions are created. Likewise, through the input of the
parameter alpha (a) four cases are defined, which show the variation of
the flow depending on the connection between its elements. Finally based
on data obtained from the literature, pressure tests were simulated in
order to verify the right operation of the equations and that are within
the error tolerance range. |
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Title: |
Improving the manufacturing technology of AlTi modifier for aluminum
alloys |
Author (s): |
Baranov V. N., Belyaev S. V., Sidorov A. Yu., Krechetov A. V., Salnikov
A. V., Potridenny V. F., Gubanov I. Y., Lesiv E. M., Gorokhov Yu. V., Kosovich A. A., Partyko E. G. and Koptseva N. P. |
Abstract: |
The paper presents the results of laboratory studies on the manufacture
of AlTi grain refiner. The developed technology includes
self-propagating high-temperature synthesis of Al3Ti from a titanium
sponge and molten aluminum; mechanical grinding of Al3Ti; adding of
ground Al3Ti particles into the aluminum melt. The modifying ability of
the experimental AlTi modifier is not inferior in effectiveness of the
AlTiB at the same titanium content in the modifiable metal. |
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Title: |
Tensile strength optimization of Zirconia based dental composite using
Taguchi method |
Author (s): |
Umesh Vishnu Hambire and Chaitali K. Mirajkar
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Abstract: |
The dental fillings in the cavity of a diseased tooth are improving by
leaps and bound. Nano composite with improved mechanical properties are
been invented. Recent composites display improved properties in specific
area. There is a need to have a holistic approach to have a improved
dental composite with balanced mechanical properties. An attempt has
been made to fabricate a dental composite using Zirconia as a filler and
Bis-Gma and TEGMA as matrix. Optimization of Tensile strength in the
experimental dental composite has been a major challenge, while
balancing other mechanical properties. Taguchi’s optimization technique
keeps the experimentation within limit giving valid results in the
domain of tensile strength optimization. |
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Title: |
Spectrophotometric investigations of the interaction reactions of
guanidine compounds with heteropolyacids of Keggin structure |
Author (s): |
Mironyak M. O., Volnyanska O. V., Labyak O. V., Nikolenko M. V., Kovalenko V. L.
and Kotok V. A. |
Abstract: |
The influence of the acidity of the solution on the properties of salts
of polyhexamethylene guanidine was studied by the UV-spectroscopic
method in this work. The studied guanidine compounds can not participate
in chemical reactions in an equivalent ratio due to the complex
structure of the molecule under certain conditions. Therefore, the
influence of the solution acidity and type of destruction on the
properties of hexamethylenediamine salts, which are the products of
chemical destruction of polyhexamethylene guanidine salts, was studied.
The possibility of a reaction between the organic cations of the studied
guanidine compounds and the anions of the 12-molybdophosphate heteropoly
acid of the Keggin structure was investigated and the nature of the bond
in the obtained compounds was determined. The composition of the
complexes and the ratio of components in the reactions of
polyhexamethylene guanidine, hexamethylene diamine and
12-molybdophosphate heteropoly acid were determined by the saturation
method. The results of these studies can be used to develop methods for
the determination of salts of polyhexamethylene guanidine and
hexamethylenediamine in various industrial facilities using the
ionometric method using potentiometric sensors sensitive to
polyhexamethylene guanidine and hexamethylene diamine. |
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Title: |
Improving the shield machine cutter head for tunneling under the
conditions of the Metrostroy Saint Petersburg mines |
Author (s): |
Dmitrii A. Yungmeister, Sergey A. Lavrenko, Aleksey I. Yacheikin and
Rustam Yu. Urazbakhtin |
Abstract: |
The paper considers the specifics of tunneling in the complicated
geological conditions of the Metrostroy Saint Petersburg mines using the
Herrenknecht S-782 shield machine. The techniques for defining the
cutting force in the tool face have been analyzed. The dependence of the
total torque of the shield machine cutter head shaft has been plotted.
An option of the cutter lacing pattern on the rotary cutter head of the
shield machine has been proposed. |
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Title: |
Signal detection in MC–CDMA system using ELM
receiver to mitigate
multiple access interference and non–linear distortion |
Author (s): |
Md. Imaduddin, Srinivas Rao, Ravikumar C. V. and Kalapraveen Bagadi |
Abstract: |
Multi-carrier code-division multiple access system support multiple users
at the same time over same frequency band. It is a multiple access
scheme used in OFDM-based telecommunication systems. Though it is a
promising wireless communication technology with high spectral
efficiency and system performance, it is prone to multiple access
interference (MAI). So, this paper mainly aims to design a MC–CDMA
receiver to mitigate MAI. The classical receivers like maximal ratio
combining (MRC), equal gain combining (EGC), and minimum mean square
error (MMSE) fails to cancel MAI when the MC– CDMA is subjected to non-linearistic
degradations. In this case, the neural network (NN) receivers could be a
better alternative. The efficiency and effectiveness of the proposed ELM
(Extreme Learning Machine) Algorithm based receiver is studied
thoroughly and explained in detailed for the MC–CDMA with non-linearistic
degradations. |
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Title: |
Next generation Main Battle Tank. Part I: Upgrading the “Pan” Tanks. |
Author (s): |
Luca Piancastelli, Eugenio Pezzuti and Stefano Cassani |
Abstract: |
Modern MBTs (Main Battle Tanks) last more than 30 years. During this
period, they will be periodically upgraded in any aspect except the
basic structure. Even the main armor is becoming an upgraded accessory
that depends on the nature of the threat. The main armament may be also
changed or upgraded. The huge electronic equipment is the most upgraded
part. The crew compartment may be upgraded in internal armor (for
example for spalling), interfaces (optics, displays, commands), safety
and protection devices (fire detection and suppression, ejection
seats..). This continuous upgrade process should be included in the
design of new vehicle, than can be modular for these mid-life upgrades.
The vehicle is designed by adding items to the crew compartment and to
the mobilization system. As an example, this first part introduces a few
options to retrofit the ARIETE MBT. The retrofit cannot be reduced to
engine and armor upgrade. A reasoned step approach is outlined in this
paper. The first minimal step is based on an active armor and an HMD
(Helmet Mounted Display) visual system. The weight increase is
compensated by reducing road wheels weight. A second step increases
firepower by installing on the main turret an automated turret with an
automatic small cannon and a machinegun. The weight increase is
compensated by limiting the internal ammunition storage of the main
cannon to the anti-tank ones. A third step converts the turret internal
ammunition storage into an automatic reloading system. In this way, the
crew is reduced from 4 to 3. A fourth step increases crew safety by
relocating the driver in the turret and by installing ejection seats.
Solutions to reduce ground pressure and to increase the effective
“power” available by replacing the final-drives and adding two electric
motors on the front sprockets are also briefly examined. It is also
highly advisable to add an APU (Auxiliary Power Unit) to reduce IR
(infrared) signature, improve main engine life and reduce maintenance. |
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Title: |
Incremental open-pit mining of steeply
dipping ore deposits |
Author (s): |
Sergey Igorevich Fomin, Vladimir
Viktorovich Ivanov, Alexander Sergeevich Semenov and Maxim Pavlovich
Ovsyannikov |
Abstract: |
Great
opportunities for improving the open-pit mining operations technology
and increasing their efficiency are laid in the temporary conservation
of overburden rocks and leaving a temporary basset edge within the
quarry. This is due to the desire to reduce the volume of mining and
stripping operations in the initial periods of quarries exploitation. To
reduce costs, it is advisable to plan incremental surface mining with
the establishment of pushbacks. Phased formation dynamics of the working
zone of opencasts and development technologies should ensure the
implementation of the projected volumes of mining and the possibility of
their simultaneous intensive development within the boundaries of
different stages. There are objective trends of deterioration of
mining-and-engineering and mining-and-geological conditions of open-cut
mining of steeply dipping deposits, in the context of dynamic markets,
changes in prices, and demand for mineral raw materials. The creation of
stages and pillars may be caused by the decision to reconstruct the
quarry. In this case, an existing final pit boundary will serve a
pushback. The process of creating a temporary basset edge was carried
out when the movement of the loading faces reached the mine abandoning
stage. Development of deposits in stages allows in some cases ensuring
the economic feasibility of mining, and the necessary rate of return.
The authors proved the necessity of forming a temporal basset edge of
ore in the context of changing economic situations. |
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