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Analele Universitatii "Eftimie Murgu" Resita. Fascicula de Inginerie
Vol. 25, No. 1 (2018)
COVER
TABLE OF
CONTENT
ARTICLES
How to Deal with Multi-sequential Decision-making Processes
Olga-Ioana Amariei,
Codruta-Oana Hamat
In this article, we started from a case study in which we wanted to develop
a proprietary design methodology of lower rank production systems,
using several softwares. Due to its complexity, the study is truncated,
making it the subject of some specialized articles. In this article
the placement of a minimal number of machines is achieved, on which
the technological flow can be achieved unidirectionally, by applying a
new method - AOI method.
Pages: 9-16
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text
The Mechanism for Actuating and Automating the Shaking Tables
Vasile Iancu
In the paper, is present the shaking table designed for the laboratory use, to simulate the earthquakes behaviors. Wi th this equipment we
can study the dynamic behavior of civil engineering structures
subjected to seismic motion. The vibratory movement of the shaking
table is carried out by means of an electric motor which, through a
crank mechanism, moves the shaking table. The smooth start of the
shaking table and its movement is accomplished through a frequency
converter, FRENIC-Mini series of general use, made by Fuji Electric C.
Ltd. Tests was performed using a NI application with a laser
displacement sensor, in order to find out the displacement precision.
Pages: 17-23
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text
Effects of Soret and Dusty Fluid on MHD Flow Past
over Inclined Porous Plate
Gaurav Kumar
This paper deals with the effects of Soret and dusty fluid on unsteady
MHD flow past over porous plate. The flow is along over inclined plate
with constant wall temperature and mass diffusion. The external
uniform magnetic field is applied perpendicular to the inclined surface.
The surface of plate is considered to be porous and fluid taken is a
viscous, incompressible, an electrically conducting. The MHD flow
model is consisting equations of momentum, diffusion equation and
energy equation. The governing MHD flow model of partial differential
equations is transformed to dimensionless equations by using
dimensionless variables. To examined the solution of the MHD flow
model, useful sets of the values of the parameters have been
considered. The governing equations involved analytically. The results
obtained have been examined with the help of graphs drawn for
various parameters.
Pages: 24-34
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text
Simulation of a Pneumatically Driven Robotic
Gripper Used for Handling Cylindrical Workpieces
Calin-Octavian Miclosina,
Mariana-Aliteia Gogoneata,
Zoltan-Iosif Korka,
Vasile Cojocaru
The paper presents the geometrical model of a robotic gripper with 3
fingers, accomplished by using SolidWorks software, used for grasping
cylindrical workpieces of the same length, but with different diameters.
Applying an action force to the grippers pneumatic cylinder piston, for
a certain cylindrical workpiece, the contact forces between the gripper
and the workpiece are determined in the SolidWorks Motion module.
Also, in the same module, a study by finite element method is
accomplished in order to obtain the highest value of von Mises stress
that occurs within the grippers finger. This value is compared to the
yield strength value of fingers material, for the verification of its
structural integrity in operation.
Pages: 35-42
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text
The Role of Virtual Laboratories in Improving
Students Learning Performance
Andrea Amalia Minda,
Gilbert-Rainer Gillich
It is known that experiments and hands-on learning are attractive for
actual students. Furthermore, visualization permits an in-deep
understanding of the learning content with beneficial consequence on
the students’ performances. Consequently, virtual laboratories can aid
students in achieving higher performances when studying machine
design. In our research, after the students have familiarized with the
theoretical aspects, they dispose of Java applets that allow performing
supplementary experiments. After performing numerous experiments,
which imply modifying the simulation parameters, it is observed that
the students thoroughly understand the studied phenomenon.
Pages: 43-51
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text
Students Perception Regarding the use of Virtual
Instruments in Teaching and Learning Process
Andrea Amalia Minda,
Nicoleta Gillich,
Gilbert-Rainer Gillich
In addition to the use by students of laboratories and hands-on
learning, teaching-learning can be improved by using Virtual
Instruments. A questionnaire was administered to find the students
opinion on the use of virtual laboratories to facilitate the understanding
of the phenomena and to eliminate some disadvantages of the real
laboratories.
Pages: 52-60
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text
Consideration of Active Fire Protection and Coating
for Commercial Buildings
Md Azree Othuman Mydin
For buildings and other constructions, fire protection is a must. The
fear of uncontrolled fires and the desire to avoid their consequences is
as ancient as human civilization. This fear has obvious enduring roots:
unwanted fire is a destructive force that takes many thousands of human
lives and destroys large quantities of asset. The primary objective
of fire protection is to limit loss of properties and lives in the event of
unexpected fires. Active fire protection is effective and efficient in most
situations. However, passive fire protection, which includes the use of
fire-proofing materials, provides an on-site fire resistance measure to
prolong the longevity of load-bearing structures. Certainly, the nature,
causes and scope of such events have changed considerably over millennia
but fear and avoidance have remained as a primary human reaction
and as an important human objective, respectively, for virtually
every society. This paper will discuss on risk posed by fire, the passive
fire protection components, conventional protection materials and
thermally reactive materials. From the review, it can be concluded that
active fire protection is effective and efficient in most situations passive
fire protection, which includes the use of fire-proofing materials, provides
an on-site fire resistance measure to prolong the longevity of
load-bearing structures.
Pages: 61-68
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text
Dry Sliding Wear behavior of some Cu and Al Alloys
Lidia Nedeloni,
Zoltan-Iosif Korka,
Marian-Dumitru Nedeloni,
Ileana
Loredana Conciatu
In this paper, a study concerning the dry sliding wear behavior of three
Cu and Al alloys namely CuSn12, CuAl10Fe3 and AlSi12 was made. For
this three alloys type, all tests have been performed with a tribometer
using the pin-on-disk method (POD) according to the ASTM G99 standard,
where the working conditions (applied load, linear speed, motor
speed and distance) were the same. As an important parameter, the
coefficient of friction (COF) versus time / distance was monitored respective
the wear rate coefficient was calculated. The obtained results
were compared between them, and the specific images were acquired
through a digital microscope and specialized software. In addition, to
these tests, the hardness of these alloys was carried out using a Vickers
microhardness tester.
Pages: 69-80
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text
Influence of Dyeing/Drying Booths Operating Parameters
on the Painted Products Quality
Arina Negoitescu,
Adriana Tokar,
Dan Negoitescu
The article proposes an analysis of the dyeing/drying booths (DDB) operating
parameters influence on the quality of products and processes
that are specific to an economic agent, which has as its object of activities
the design and production of integrated systems made of advanced
composite materials, metallic materials and sandwich materials with different
cores. In order to assess the product conformity, the production
flow of products made of resin reinforced with glass fiber was followed
and quality control of painted products was performed by final inspection.
Final inspection is an essential factor in any scientific system of
production organization and management. There have been highlighted
measures in order to solve the spray-painted products nonconformities
caused by the change of the dyeing/drying booths operating parameters.
In this sense, solutions are proposed in order to correct the defects
through three main actions.
Pages: 81-90
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text
Waste Minimization Strategy and Technique:
Towards Sustainable Waste Management
Nurhafiza Mohd Noh,
Md Azree Othuman Mydin
Generally, sustainable waste management aids construction key players
to diminish and making better use of material on their construction project.
The waste minimization strategy is not only implemented during
the construction stage, but it record and estimates the use materials
through whole project delivery process, in order to decrease the
amount of waste requiring disposal at landfill and as a consequence,
fully mitigate the interrelated cost, strengthen competitive advantage
and environmental benefits. The implementation of waste minimizing
plan method is an opportunity to increase profit of construction company
through identification of valuable waste and invaluable waste to
gain profit. Businesses can create value through the return of construction
wastes back to recycling and manufacturing processes into new
products. Hence this paper will present the waste minimization strategy
and technique towards achieving sustainable waste management
Pages: 91-98
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text
Mechanical Tests of the Dissimilar Welded Samples
by Friction
Adrian Valentin Petrica
The paper presents the experimental achievement of heterogeneous
joints, with dissimilar materials, as well as the analysis of these joints
by mechanical and metallographic tests. After traction testing of the
specimens, it was found that breaking occurred each time in the area
of the base material, which leads to the conclusion that the strength of
the welded joints is above the resistance of the base materials used.
Pages: 99-104
full text
The Quality Analysis of the Thermal Sprayed Deposited
Layers by Electronically Microscopy
Adrian Valentin Petrica
The analysis performed by electronically microscopy lead to obtain the
experimental data under tabular form. A linear chemical quantitative
analysis over a 228.87 ?m length was made of on a microscopically
image at 250x magnification. The number of points where analyze was
made of is 512. Due to the higher number of points which were used
for marking of these curves, the interpretation is difficult. Therefore, is
necessary an additional assessment processing of these curves which
can permit the interpretation of the quantitative chemical analysis.
Among the processing versions of the curves, the average for a number
of values, choose dependent on the follow purpose, lead to some
curves which permit the interpretation of the results.
Pages: 105-110
full text
Making Mosques Physically & Socially Accessible:
Lack of Facilities for People with Disabilities
Farah Nuratiqah Rusli,
Md Azree Othuman Mydin
Malaysia is a country which is known for the heavy Islamic moral values
presented in its culture and traditions. Mosques in Malaysia are well
known for their beauty and captivating architecture. There are 5,300
mosques built in Malaysia as of November 2017 and the number is increasing
as the years pass, but the accessibility of amenities for the
PWDs is still a major problem. The mosque is not just for those without
disabilities, therefore it is important to provide accessibility as to give
the PwDs an equal opportunity for them to perform congregational
prayers together with other devoted Muslims in respect of helping them
perform their responsibilities and their social roles. Throughout history,
community attitudes and physical obstructions in the built environment
have barred PwDs from fully participating in the society. Access to education,
employment, housing, recreation, cultural events, and transportation
were denied to many people. These days, along with the emergence
in the PWDs population, the mission for impartiality and equal
rights is carried out aggressively. Currently, major changes in design
requirements, both market-driven and legally mandated, are creating a
new life system for PWDs and a new path for designers. This paper will
present some of the major dilemmas faced by PwD’s when they
perform prayers at mosque. Most of the mosque lack of accessibility
and amenities for PwDs. Besides, PwDs are part of a community that
needs to be assisted so that they can worship in comfort with the
others. They also have equal rights and opportunities to live like other
community members.
Pages: 111-117
full text
Accessible Built Environment for People of Disabilities
at Mosque: Universal Design
Farah Nuratiqah Rusli,
Md Azree Othuman Mydin
People with disabilities (PwDs) face challenges which effect on their capability
to complete everyday activities such as moving around, communicating
and fulfilling social roles and the social participation assumes
individuals with disabilities live within their community and interact
with others. In the right of person with disability have been evidently
specified in Person With Disability Act 2008 which its stated that
it is oblige to recognize the interaction with the disable which hinders
their full effective participation in society on equal basis with person
without disabilities, and also to value theirs involvement to the community
and society. This paper will present the component of universal design
in the context of mosque and review some of the legislation and
standards related to design of facilities for PwD’s at mosque. There is a
positive development in terms of public awareness on access and facilities
for PWDs in Malaysia even though the accurate understanding of
universal design theory is still low among Malaysian society. Some people
have misunderstood that universal design is exclusively caters the
needs of PWDs access and facilities in the built environment.
Pages: 118-125
full text
A Solution to Reduce Pollutant Emissions by Recovering
the Flue Gases Waste Heat
Adriana Tokar,
Arina Negoitescu,
Dan Negoitescu,
Marius Adam
From the point of view of the energy efficiency improvement and environmental
protection, the recovery of waste heat from thermal systems
is a necessity. The heat recovered through an economizer is a viable
solution in order to achieve energy savings. For this reason, the article
deals with a solution for recovering a quantity of thermal energy exhausted
into the atmosphere through the dyeing/drying booths (DDB)
burners stove pipes at an economic agent. The study illustrates the importance
of recovering heat from flue gases in order to reduce pollutant
emissions.
Pages: 126-131
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text
Analele Universitatii "Eftimie Murgu" Resita. Fascicula de Inginerie
Vol. 25, No. 2 (2018)
COVER
TABLE OF
CONTENT
ARTICLES
Pre-processing of Images as a Source of Additional
Information for Image of the Natural Polymer Composites
Cornelia Victoria Anghel Drugarin,
Vyacheslav V. Lyashenko,
Muncho J. Mbunwe,
M. Ayaz Ahmad
Image processing is one of the methods of analyzing and obtaining
new information. Image processing methods can be applied to any image.
Image processing is used in various fields of research. Among the
stages of image processing, the stage of image pre-processing is important.
This stage allows increasing the efficiency of the analysis of
the original image. We considered the use of pre-processing for the
analysis of natural polymer composites image. In this paper, we describe
the possibilities of automatic processing of natural polymer composites
image.
Pages: 11-16
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text
Comparative Aspects of the Temporal Characteristics
of the Production of Various Plastic Products
Cornelia Victoria Anghel Drugarin,
Mohammad Ayaz Ahmad,
Vyacheslav V. Lyashenko
Plastic has a special place in the manufacture of various products. Production
of plastic products consists of several stages. Each stage has its
own time characteristics. Thus, the duration of the production of plastic
parts depends on the individual stages. A comparative analysis of the
time aspects of the formation of various plastic products showed that
the duration of the molding process is affected by the holding time under
pressure, the time of pauses.
Pages: 17-24
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text
Optimizing the Geometry of a LHy-M Hybrid
Locomotive’s Chassis by Resistance Calculations
Aurel Bara,
Dorian Nedelcu,
Corneliu Dica
Starting from the initial geometry of the LDH 1250 CP locomotive
chassis, the work aimed to optimize the geometry in the sense of maximum
stresses reduction by geometric changes and the reinforcement
of the structure. The optimization resulted from the need to transform
the LDH 1250 Hydraulic Diesel Locomotive into the LHy-M Hybrid Locomotive,
encompassing hybrid technology, powerful automation
elements, as well as ergonomic redundant components that can complement
and assimilate the extensive features of the old components of
the rolling stock.
Pages: 25-34
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text
Thermal Calculation of the Reduction Gear
2XAB/StCu110So as Part of Hybrid Locomotive’s
LHy-M Mechanical Transmission
Aurel Bara,
Dorian Nedelcu,
Corneliu Dica
The purpose of this work is to present the reduction gear’s efficiency,
reduction gear that is load part of hybrid locomotive’s mechanical
transmission. The purpose of the calculation is to determine the overall
efficiency of the reduction gear to determine its operating temperature.
Pages: 35-40
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text
Exploitation Solution of the Wind Potential in the Danube Gorge
Petru Chioncel
This paper proposes a solution to exploit the wind potential of the Danube
cluster by storing it in the Iron Gates I reservoir lake, through
pumping the water downstream of the hydroelectric power plant. Storing
energy by pumping water, i.e. turning the plant into a pumped
storage hydroelectric plant, will chancel the unstable character of wind
energy, also achieving peak load coverage under conditions of investment
much be-lower to those of building a hydroelectric power plant
with accumulation by pumping the Danube.
Pages: 41-46
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text
Theoretical and Experimental Research on the Reliability
of Parts Rehabilitated by Arc Welding
Lenuta Cindea
The paper presents a technical-experimental study encountered in the
repairs of the rotor blades to Kaplan turbines due to cavitation wear
due to the cyclical stresses of the surfaces in contact. The repair of the
Kaplan turbine rotor pallet was performed for the purpose of metal
deposits to compensate for wear, to recover parts with cracks, cracks
or bursts in the base material in order to reduce major costs associated
with the operation and maintenance of the installations and equipment
that make part of the production process.
Pages: 47-52
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text
Static and Fatigue Analysis of the Hydraulic Cylinder
and Tensile Device from an Uniaxial Testing System
Vasile Cojocaru,
Ovidiu Jitareanu
The paper presents the static analysis and the fatigue behavior analysis
of the components of a tensile test equipment (hydraulic cylinder and
tensile device), designed for didactic applications. The stress and the
displacements that occur in the limit-loading approaches are calculated
using static FEM analysis. It is also investigated the possibility of using
the hydraulic cylinder and the tensile device in a redesigned equipment
used for fatigue tests.
Pages: 53-58
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text
Computing of the Slot Number within the Induction
Machine Approached in Terms of Electromagnetic Forces
Ion Dobrota,
Ion Paraschiv
In order to find the final solution the design of electrical machines usually
involves different steps. In the starting stages of design procedure,
some of the main variables are given data and all the others must be
adopted by a proper approach. This paper proposes a method for determining
the total slot number within the induction machine by approaching
electromagnetic forces that leads to a particular relationship.
The final solution is checked by some manufactured induction machine.
Pages: 59-68
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text
Aspects regarding Influence of Voltage Disturbances
upon Reluctance Synchronous Motors Operation
Monica-Adela Enache,
Aurel Campeanu,
Sorin Enache,
Ion Vlad
In this paper there is analyzed, by simulation, the behavior of a reluctance
synchronous motor, in case of two dynamic states caused by
modifying the supply voltage. The mathematical model used, the Matlab
program and the simulations obtained are presented. The paper
ends with conclusions resulted by analysis. There is emphasized the
fact that the dynamic stability of the motor is determined by the voltage
value, as well as by the machine parameters. By simulation it is
possible to establish the stability range and the ways of increasing the
stability can be identified. The simulations are an absolutely necessary
stage in the motor dimensioning stage.
Pages: 69-76
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text
Power System Health Monitoring Based on Energy
Losses using Genetic Algorithm
Andrei Ioanes,
Radu Tirnovan
System health assessment becomes ever more important as consumers
take for granted the apparent infallible character of power supply and
the extremely high costs of prolonged down times. A system that
achieves minimum operational disruptions becomes a target for all grid
operators. This paper tackles the system heath issue in distribution
networks by evaluating overall network losses. Using a genetic algorithm,
the system health is evaluated considering key elements within
the network operation.
Pages: 77-86
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text
Assessing the Level of Electromagnetic Pollution
through Statistical-probabilistic Methods and Fuzzy Logic
Marius Savu Lolea,
Emeric Remus Szabo,
Cornelia Victoria Anghel Drugarin,
Petre Cret
This paper is dedicated to the analysis of the possibilities of assessing
the level of electromagnetic pollution in the public spaces and the lucrative
areas on the application of some statistical and probabilistic
methods and by fuzzy modeling. The proposed models are applied to
several components of the electrical grids located in Oradea or Bihor
County.The first part of the paper ishows the statistic-probabilistic
methods. There are presented models for calculating the level of
electromagnetic pollution based on the probability of exceeding the
dangerous threshold values of the characteristic magnitudes of the
electromagnetic field. The second part is allocated to assessing the
level of electromagnetic pollution by using fuzzy logic. There are
elaborated models for fitting the values of electromagnetic field values
into the risk levels given by the exposure of the organism in the electromagnetic
field. By using the fuzzy toolbox from the Matlab software,
the rules of inference for the specific conditions of electromagnetic
field exposure and exposure, applied in power plants in Bihor
County, are applied.
Pages: 87-98
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Connection of Renewable Energy Sources to the
Regional Power Systems. A Short Analyze
Marius Savu Lolea,
Emeric Remus Szabo,
Cornelia Victoria Anghel Drugarin,
Petre Cret
Among the basic problems that are involved in the decision to implement
an energy project with Renewable Energy Sources(RES) are
the identification of resources and the assessment of their regional
potential, the possibilities of connecting to the existing electricity
network in the area, the efficiency of conversion of natural RES in
electricity, sources of financing and the possibilities of expanding the
regional energy system based on RES. Then there are problems of
endowing with modern RES-based power plants, the quality of the
electricity supplied in the grid, the reliability of the connection
schemes and the continuity of the power supply while reducing the
energy losses on the grids. All these problems can pose risks to prevent
the construction of a RES power plant or the good functioning
of RES connected to the regional power system. In the paper, these
aspects are analyzed by the authors in accordance with the renewable
energy resources and the existing RES on the territory of the Bihor
County.
Pages: 99-106
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text
Quadcopter Stability Increased by PID Adaptive
Tuning
Ion-Cornel Mituletu,
Elisabeta Spunei,
Emanuel Markovican,
Ion Popescu
Today World is getting more efficient in mail deliveries or other applications
using autonomous vehicles as drones because of their improved
performances. The quadcopter appertains to the drone family having
the advantage of flying stability light weight and accurate maneuverability.
This paper describes the design and the adaptive tuning for dynamic
control of a quadcopter using PID control technique. The experimental
tests show improved response related to the previous results
under the same input conditions.
Pages: 107-112
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text
X-Y Pen Plotter Design Accomplished from Older
Drives
Ion-Cornel Mituletu,
Adrian Sirbu,
Bogdan Cristian Marinescu
The paper describes the design and the implementation of a small, easily
operable and flexible 2-axis CNC pen plotter (Computer Numerical
Control). It is accomplished from two old and available CD-ROM
(Compact Disc Read-Only Memory) drives using their stepper motors
and the main hardware structure. The two stepper motors move the
pen platform along X and Y axis. The plotter has been tested for printing
different images and texts. Thus, the functional and graphical requirements
were demonstrated, the conclusion being that this device is
efficient and precise, and it can be easily achieved from available components.
Pages: 113-116
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Digital Control of Centrifugal Air Compressors
Filip Niculescu,
Adrian Savescu,
Mirela Vasile
The air installation consists of high-capacity centrifugal compressors
which pumps in parallel in an industrial pipe. The total air flow rate of
the compressors in the pipe can be adjusted by acting on the air
suction valve of each compressor so that the shut-off or opening of the
compressor valve can regulate the flow rate of each compressor, which
results in total flow control. The problem is to replace the analog
control of the compressors with a digital control. If we have two types
of compressors in the plant, the automatic setting involves closing or
opening the suction valve of the compressors in a certain order so that
besides the total objective to pump a particular flow we also have high
energy efficiency.
Pages: 117-126
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The Importance of Optimal Design in Outdoor Light
Source Positioning
Elisabeta Spunei,
Ion Piroi,
Florina Piroi,
Daniel Brebenariu
In this work we underline the importance of the optimal design for outdoor
light systems such that light posts and sources are placed correctly.
We present a case study where we considered a city road section
equipped with LED sources. On this section, we measured technical
luminous coefficients, which were then compared with values listed
in standard and normative documentation. Based on this we did a new
design that had to follow certain requirements on street and lighting
post configuration. Comparing the two designs we conclude that, to
have an optimal street light system, the engineer must aim for the best
possible design and consider this when deciding on the position of the
light sources.
Pages: 127-136
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Sigma-demicontractivity and Strong Convergence of
Mann Iteration
Irina Maria Terfaloaga,
Mihaela Dorica Stroia,
Lenuta Cindea
The problem of additional conditions ensuring the strong convergence
of Mann iteration for demicontractive mapping is investigated. A critical
analysis of ?-demicontractivity condition is performed showing the applicability
and how strong this condition is.
Pages: 137-142
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Fuzzy Logic Controllers for High Performance in
Secondary Cooling
Gelu Ovidiu Tirian,
Cristian Paul Chioncel
The main target of this paper is to develop and implement structures of
fuzzy control in the continuous casting process (in the secondary
cooling) capable of eliminating the surface flaws and casting rejects, to
increase the quality of continuously cast products and implicitly to
increase the productivity of the installation by controlling the water flow
rate in the secondary cooling circuit. In order to achieve this objective,
a solution will be developed and implemented, meant to control the
casting process by a fuzzy system, allowing the control of the water
flow rate in the secondary cooling, by appropriate distribution along the
cooling area. This necessity is imposed by the fact that actual control
systems do not correlate in real time the variations of the multiple
variables related to the continuous casting process and stick to a rigid
distribution of the water flow rate on each cooling area.
Pages: 143-154
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Modeling of Complex Shaped Cracks
Cristian Tufisi,
Gilbert-Rainer Gillich
The paper proposes modeling approaches of complex shape cracks.
Structures may present many types of defects, of different irregular
shapes and sizes, due to various reasons, and so it is very important
for the model of the crack used to be accurate. There are three main
categories for modeling of cracks; local stiffness reduction, discrete
spring models, and complex models in two or three dimensions each
proving to be reliable methods for generating finite element models.
Pages: 155-162
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Analysis of the Influence on the Thermal Regime of
the Slot Shape within an Induction Machine
Ion Voncila,
Ion Paraschiv,
Madalin Costin
The paper analyzes the influence of the slots shape pertaining to induction
motor armatures on the temperature development within its structure.
The analysis of the temperature distribution within the studied
motor was made using the Motor-CAD programming environment. The
stated aim of the study was to emphasize the importance of choosing
the geometrical shape of the slots of a classic rotating electric machine,
still in the design phase, in order to obtain the validation - by thermal
calculation - at the end of the design, of the geometrical structure that
offers the highest technical and economic performance.
Pages: 163-174
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