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Home>Products>Journal and Reviews>I.RE.M.E.>Latest issue
International Review of Mechanical Engineering - November 2011 (Vol. 5 N. 7) - Papers
International Review of Mechanical Engineering - Papers
Abstract - This study apply an integrated symbolic power series method - Padé approximants technique (PS - Padé) to solve a system of nonlinear differential equations arising from the similarity solution of viscous flow over a nonlinear porous shrinking sheet, variable magnetohydrodynamic effects and suction or injection. Combination of power series solution with the Padé approximants is used to handling boundary value condition on the semi-infinite domain of solution. The obtained results are compared with numerical results as well as other results in the literature. The results have good agreement with numerical and other results. It is found that velocity profiles and skins fractions are increased with increase of mass suction or magnetic effects. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Nonlinear Magnetic Flow, Shrinking Sheet, Similarity Solution, Power Series, Padé.
Abstract -
Influences
of variable parameters such as pouring temperature (700-740oC), slurry
viscosity (20-26s), vibration time (30-90s) and sand size (30-100 AFS)
in terms of heat transfer and surface roughness during lost foam casting
(LFC) of LM6 alloy were investigated. In this paper those process
parameters have been systematically investigated and the effect of
different casting parameters has been determined. Surface roughness is
primarily dependent on production process, mould material, melt
treatment and cooling condition or heat transfer. Heat transfer of
molten materials is an important factor to change the microstructure and
mechanical properties which is considered in the present study. A full
2-level factorial design experimental technique was used to identify the
significant factors that effect on heat transfer and surface roughness
of castings. The results show that increasing pouring temperature
resulted in decreasing heat flow and surface. However other parameters
do not exhibit significant influence on those features.
Keywords: Lost Foam Casting, Full Factorial Design, Surface Roughness, Pouring Temperature, Aluminium, LM6.
Abstract
- A Capillary Pump Loop (CPL) is a two-phase heat transfer device
considered a useful solution for thermal control applications in
spacecrafts, satellites and electronic components. Purpose of this paper
is to study variable aspects of the working state of the Capillary Pump
Loop. A porous structure with partial heating and evaporation on the
upper surface is studied analytically. Liquid pressure and velocities
were obtained by solving a Laplace-type equation for the porous
structure. The same porous structure was examined for the same boundary
conditions using Computational Fluid Dynamic, CFD, in order to check the
agreement between the two solutions. Different cases were studied
concerning the working fluid, geometric parameters, thermal
conductivities and heat load applied to the Capillary Pump Loop, CPL,
evaporator.
Keywords: Analytical Solution, Evaporator, Heat Transfer, Two Phase Flow.
Abstract - Several
researches investigated effect of various components on the final
quality of fabricated parts through deep drawing process using
statistical methods. But there is no specific research about impression
of effective process parameters in different geometries, including
symmetrical, asymmetrical, curved, flat or angular and clarification of
qualified design requirements of this parameters according to the
product geometry. Most of the research about effective parameters on
deep drawing process and the quality of the products have been on
special geometries and there is no appropriate information on sheet
metal forming mechanics, the condition and intensity of impression
related to the parameters in other geometries. In this article we have
tried to investigate the effectiveness and the importance level of six
different parameters on the least final thickness of the fabricated part
in deep drawing process using punches whit symmetrical and asymmetrical
geometries through Taguchi method in the design of Experiments (DOE).
The parameters under study include a portion of the most important blank
mechanical properties, forming devices and deep drawing process. The
results have been achieved by simulations in Abaqus software and have
been verified through experimental tests.
Keywords: Deep Drawing, Taguchi Method, Finite Element Method (FEM), Analysis of Variance (ANOVA), Design of Experiment (DOE), Sensitivity Analysis.
Abstract – The demand of ultra thin plastic parts in global industries is increasing today. Ultra thin plastic parts are widely produced using injection molding processes and it is understood that warpage issue is regularly found in producing these parts. This situation happens due to lacking of knowledge in selecting the best injection molding parameters to produce parts with minimal warpage. In addition, designers also have difficulties to control the parameters since the 0.3mm thickness of the ultra thin parts is too hard to maintain. Therefore this study is performed purposely to determine the best parameters can be selected in manufacturing ultra thin plates. Two types of gating systems which are side gate for 2-plate mold and pin point gate for 3-plate mold are tested. The results are obtained using Taguchi Method and Analysis of Variance (ANOVA) and run through simulation software. Both parameters are then compared with each other in recommending molding designers which is the best to be applied at mold design stage. Results from this research recommend using pin-point gate for 3-plate mold using the outlined parameter setting in order to obtain the minimal warpage of ultra thin wall plastic plates. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Thin Plates, Injection Molding, Warpage, Taguchi Method, ANOVA.
Abstract -
Evaluating approximate frequency for isotropic and orthotropic plates is a
complicated problem, thus exploiting the general formula of Hearmon, it
is proposed in this investigation to calculate the fundamental mode of
isotropic and orthotropic plates with two non-homogenous supports
(cases: SCSC & SSCC). For the higher mode of modal frequency, a
particular form of Rayleigh’s method is used leading to a simple
procedure for calculating the fundamental frequency. A new simple and
qualitative method is proposed and has permitted a good strategy to
evaluate the quality of results obtained. In order to verify the
precision of the proposed qualitative method, a confrontation with
finite element method using ANSYS software was done. The complementary
utilization of Hearmon’s principle and the qualitative method has also
permitted a successful advance in evaluating higher modes. This combined
procedure gives a strategy of a vibratory analysis of isotropic and
orthotropic plates; it permits the satisfaction of the preliminary
conception needs of the structure to be studied, and also provides a
qualitative method for expertise and investigation of dynamical
responses. In all cases, the dynamic investigation is based on some
evaluation criteria such as: limit conditions effect, plate dimensions
ratio effect, material effect and mode number effect.
Keywords: Free Vibration, Rectangular Thin Plates, Isotropic, Orthotropic, Circular Frequency, Nodal Lines Position, Qualitative Analysis Method, Rayleigh Method, Finite Element Method.
Abstract - With the increasing development of space industry, the idea of making the sandwich columns with high strength and light weight has been formed. In this article, static and dynamic buckling of the sandwich columns has been investigated in theory and with using ABAQUS software. First the buckling behavior of homogeneous steel column has been investigated then this column has been replaced with another column that has the same dimensions but it has been made of two layers of steel with aluminum core. The second column has weight and hardness less than the first column. It was designed with minimal changes in the critical buckling force that a lot of weight loss has been created in the column. This is very important for the Aerospace Industry. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Static Buckling, Dynamic Buckling, Impact, Sandwich Columns, Composite Columns.
Abstract -
The article discusses a calculation procedure for determining the load
distribution on the threads of a ball screw under general load
condition. The equations for calculating of axial load distribution for
two types of loading are presented. The factors influencing the
pliability of threads are calculated and their dependence on the
pressure angle between balls and elements of transmission is shown. The
value of the increment of pressure angle is calculated and the load
distribution in a ball screw and a sliding screw is shown. For the ball
screw the change of loading for constant and variable pressure angles
are considered. Ball screw mechanisms with two and four contact-point
rolling elements are considered and equations for calculating of bending
and shearing deformations are presented. Radial deformations from
contact forces are considered and a simple method for analysis of
contact deformations between the balls, screw and nut of the
transmission is shown.
Keywords: Ball Screw, Two and Four Contact-point, Herzian Contact, Lame's Solution, Pressure Angle, Load Distribution .
Abstract -
Contact surface teeth temperature represents a problem of a real
interest since the most commonly encountered mechanical power
transmission failure is the thermal damage. This paper presents an
optimal design minimization problem of the teeth contact surface
temperature for a helical gear set using genetic algorithms (GAs). The
objective function (i.e. the contact surface teeth temperature) was
computed according to ISO/TR 13989-1 norms. It is observed that the
proposed GA offers better helical gear design solution as compared to
the classical design.
Keywords: Optimal Design, Genetic Algorithms, Helical Gear Set.
Abstract -
Every thing in universe which posses mass possesses stiffness and
intrinsic damping. Due to stiffness property mass will vibrate when
excited and its intrinsic damping property will tend to cease vibration.
Every design engineer put his knowledge to make vibration free machine
and if it is not possible to do so then attempts will be made to give
proper damping effect which increases the system damping near to
critical damping. Particle impact damper (PID) is a very interesting
passive damper in which the impact and friction phenomenon of particles
are involved, which are the means of energy dissipation. The unique
aspect of PID is high damping achieved by absorbing the kinetic energy
of the structure as opposed to the more traditional methods of damping
where the elastic strain energy stored in the structure is absorbed and
converted to heat. PID is a means for achieving high structural damping
by the use of a particle filled enclosure attached to the structure. The
particles absorb kinetic energy of the structure and convert it to heat
through inelastic collisions between the particles & the wall of
enclosure, and amongst the particles themselves also. In this work,
behaviour of PID is studied for a cantilever mild steel beam with the
enclosure attached at four distinct locations along beam and copper
particles have been used of diameter 3mm. The effect of location and
packing ratio on acceleration and displacement amplitude of beam is
studied. PID is found to be highly non-linear. Perhaps the most useful
observation is that the effective location is one where maximum
amplitude of vibration is observed, also packing ratio influences the
damper’s performance. The effect of damping is studied with and without
particles. A satisfactory comparison between the damping performance of
beam can be observed through experiments when particles are used and
when not used. The effective location of cavity was found amongst four
different locations also the effective packing ratio can be identified.
It was also shown that as packing ratio changes, the contribution of
impact and friction phenomenon towards damping also changes. An
encouraging thing is that in spite of its deceptive simplicity, the
model captures the essential physics of PID.
Keywords: Particle, Impact, Friction, Damping, Vibration.
Abstract - Research on numerical schemes on fluid-solid interaction has been quite intensive in the past decade. The difficulties associated with accurate predictions of the interaction at specific spatial and temporal levels. Traditional computational fluid dynamics schemes are struggling to predict at high level of accuracy for this type of problem. Hence, in the present study, an alternative numerical scheme was proposed to predict the fluid flow and coupled with a Lagrangian scheme on the prediction of solid phase. The dynamics of solid particles in an enclosure and a channel with a cavity were investigated at a wide range of Reynolds numbers. The results show that the particle trajectories are critically dependence on the magnitude of Reynolds numbers and the vortex behavior in the cavity. Good comparisons with the previous studies demonstrate the multidisciplinary applications of the present scheme. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Fluid-Solid Interaction, Lattice Boltzmann Method, Cavity Flow, Solid Particle.
Abstract - In this paper, a new variant of Shan-Chen multiphase model is used to compute the dynamics of droplet on non-permeable solid surface. The results are compared with published analytical solution for such flow configuration. The modified multiphase model demonstrated good agreement, which further supports its validity in computing multiphase fluid flow. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Lattice Boltzmann Method, Shan-Chen Model, Phase Separation, Contact Angle.
Abstract -
Several forces have shaped the technological development of the
automobile vehicle, during its more than one hundred years of existence.
This paper takes a historical perspective of the role of society and car
users in the development of the automobile. The focus on the emergence
of diesel powered engines, and their ongoing success as a viable
alternative to the gasoline powered engine, sheds light on the
prerequisites for technological change in the automotive power drive.
Currently, as the automotive vehicle is at crossroads with the
widespread adoption of the electrical drive, analyzing contextual
factors framing the diesel challenge to the gasoline powered engine
assists in developing a systems understanding of the socio-technical
requirements electric automobility designs need to satisfy in order to
increase their prospects for wide user adoption and success.
Keywords: Automotive Technology Change, User Adoption of Automobiles, Automotive Infra-Structure, Automobile Paradigm.
Abstract - The main aim of study is to compare Finite Element Analysis results with Critical Distance Approach and study of prediction of fatigue failure in engineering component. The term Failure of a material may be defined as its fragmentation or separation, under the action of an external force, into two or more parts. It may occur as a sudden breaking up of a material either as the result of extensive plastic deformation or as a result of fatigue in a part of the material. The term ‘Fatigue Failure’ may be defined as the fracture which takes place under repeatedly applied fatigue stresses. It occurs at stresses well below the tensile strength of the materials. The ‘Fatigue Failure’ takes place due to initiation of the micro cracks at the surface of the material. The micro cracks act as the points of stress concentration. The theory of critical distances (TCD) is group of method which is used to predict the failure when a stress concentration (e.g. a crack or notch) is present. Accurate prediction is possible when elastic stress information in a critical region close to the notch tip is available, which may be found out by Finite Element Analysis. In this method, the critical region is defined in terms of a characteristic material length constant, L, which is a function of the fracture toughness Kc and a failure stress, σo. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Stress Concentration, Notch, Critical Stress, Stress Intensity, Critical Length and Crack.
Abstract - This paper discusses the use of the Taguchi method of experimental design in optimizing process parameters of adhesion strength between tile and mortar bed. The effects of four process parameters of force, thinset mortar thickness, shape of ribs and vibration motor speed have been explored. The primary response under study is the adhesion strength. An L9 orthogonal array was used to accommodate the experiments. The study predicted that the highest adhesion strength could be obtained with force of 15N, thinset mortar thickness of 4mm, V-shape of thinset ribs and speed of 2500 rpm for vibration motor. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Taguchi Method, Parameter Optimization, Thinset Mortar.
Abstract - Construction industry is very important to the developing country like Malaysia. Many challenges and difficulties must be faced by the developers of this particular field. Warszawski et. al [1] has reported that there are four serious problems in the construction industry today; low labour efficiency, high accident rate at construction sites, poor finishing or workmanship and insufficient supply of skilled workers. In Malaysia, construction companies usually employ migrant workers due to their lower salaries. International Labour Organization, 2001 in their report has stated that 80% of the entire construction workforce in Malaysia is foreign labour. This scenario causes imbalance of the services account and affects the country’s economic system [2]. One of the ways that possible to overcome this issue is to mechanise or automate some of the manual construction activities. This paper discussed about an approach to mechanize and automated one of the manual activities in construction site which is manual tile laying process. This activity will be demonstrated as a case study where the process will firstly mechanized and then will be automated if possible. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: IDEF, Tile Laying Process, Automation, Mechanization, Design Process.
Abstract - Analysis of the industrial robot application has created for four continents: America, Asia/Australia, Europe and Africa where has been analyzed yearly installation and operational stocks of the industrial robots in the period of time 2005-2010. The analysis is given for following industrial branches: agriculture, forestry, fishing, mining, food product and beverage, tobacco products, textile products, paper products, wood products, leather products, metal products, chemicals and chemical products, electrical/electronic product, motor vehicles, construction etc. The analysis shows increasing trends of the industrial robot applications in various industries branches in 2010 comparing with 2009 such as motor vehicles industry, electrical/electronic industry and metal product industry. The motor vehicles industry takes the first place with 36% of the industrial robot installations of the total yearly supply. In the motor vehicles industry the larges number of industrial robots has installed in China, Republic f Chorea, Germany, North America and Japan. Electric/electronic product industry had an increasing trend of the industrial robot application in 2010, mostly large product companies in the following countries: Republic of Chorea, Japan, USA, China and Taiwan. In the chemical product industry increasing trend has marked in Japan, North America, China, and Germany. Installations of industrial robots in 2009 marked decreasing trend mostly because of global economic crisis but good news is increasing trend in 2010. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Industrial Robots, Industry, Robot Application, Manufacturing, Metal Product Industry, Motor Vehicles Industry.
Abstract - This article discusses on a research experience and finding based on a collaboration with a medical equipment manufacturer in producing urinary catheters. The manufacturer had been spending high cost yearly to replace more than 1,000 units of side arms on each design of catheter. It is found that new side arms made from Nylon PA66 using an injection molding process is much more cost effective. While producing the new side arms using an injection molding process, this article also discusses on an analysis made in predicting the most significant injection molding process parameters involved in producing Nylon PA66 side arms that led to a popular warpage issue. The parameters concerned are melt temperature, filling time, packing pressure and packing time. A model of side arm is designed and simulated using simulation software to imitate the real operation of an injection moulding process. These parameters are then analyzed with respect to the deflections occurred using Taguchi method and further verified by using Analysis of Variance (ANOVA) technique. At the end of this study, it is found that melt temperature and packing time play the most significant role to the existence of warpage of side arms made from Nylon PA66. At the end of this research, it is found that nylon can be an alternative material in manufacturing side arms in reducing cost of manufacturing at 83.3% which is used in manufacturing urinary catheters. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Nylon PA66; Injection molding; Warpage; Taguchi; ANOVA; Catheter.
Abstract - Integrated Definition for Function which is also known as IDEF is a well structured modeling method that corresponds to a manufacturing system. For IDEF3, it is a process description capturing method created to capture descriptions of specific sequence activities. This article discusses the details of how IDEF3 is implemented and applied in mapping a tile installation process as it is known that IDEF3 has an ability to construct a well structured methodology or processes and enabling the process to be fully understood. Taking an example of IDEF3 process schematic in representing a tiles installation process, this article then shows a number of activities which can be identified as surplus to get it combined, simplified or removed and it is understood that the new IDEF3 diagram of tile installation process can be used to design and develop a better conceptual activities. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: IDEF, Tile Laying Process, Automation, Mechanization, Design Process.
Abstract - Thin shallow plastic parts are widely produced using injection molding processes in producing varieties of components and applications. Warpage issue always happens in manufacturing thin shallow parts due to its uneven shape of the parts and also due to lack of knowledge in selecting the best injection molding parameters to produce with minimal warpage. Due to uncertainty of selecting the best parameters in reducing warpage issue, hence this study is performed purposely to determine the best parameters to be selected in manufacturing thin-shallow parts. Three types of polymer materials are selected for experimentations and the results are obtained using Taguchi Method and Analysis of Variance (ANOVA) and run through simulation software. All parameters are then compared with each other in recommending molding designers which is the best to be applied at mold design stage. Results from this research recommend polypropylene as the best parameter in order to obtain the minimal warpage of thin-shallow parts. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Thin-Shallow Parts, Injection Molding, Warpage, Taguchi Method, ANOVA.
Abstract -
In this study, a different design aspect of a simplified front side rail
structure of an automobile body (S- Rail) from the point of view of
crashworthiness parameters which are crushed energy absorption and force
response and also weight efficiency is studied. Various orientations of
cross section design and various material replacements have been applied
to investigate their effects. The specific energy absorption (i.e.
Energy absorption per unit weight) is taken as a measure of the
performance of a structure. Effect of different cross section with model
cross section horizontally ‘hat – type’ model (shape 5) given greatest
energy absorbed. This model then being analyzed with different material
such as mild steel, aluminum, Hastelloy X alloy and Fiberglass Polyamide
(PA – 66). Hastelloy X alloy result the highest increment in ability to
absorbed energy during collision. The consideration of various cross
sections and the best material selection of replacement then been
discussed and compared for suitability from the aspect of
crashworthiness, safety of passengers, weight efficiency and cost to
automobile industry.
Keywords: Crashworthiness, Cross section design, Material replacement, Energy absorption, Force responses, Weight efficiency.
Abstract - In this
study, an electrical furnace for firing the ceramic products which its
heat reaches up to 1000 ºC has been designed and temperature control has
been accomplished. The temperature values inside the furnace have been
read from three different zones via K type thermocouples and temperature
has been controlled through PIC 18F452 microcontroller. In the study
which has been conducted the furnace can be operated in 10 different
temperature zones for any step desired temperature and time values.
Temperature values in the furnace, entered temperature and time
information and current value drawn from the electric network by the
furnace have been displayed on the LCD screen.
Keywords: Automation, Ceramic Product Cooking, Electrical heating, Furnace Firing Control, Microcontroller.
Abstract -
New cable gland design that incorporates 360 degree grounding is presented
and tested in this paper. This kind of grounding is recommended to be
used in power electronic converter based applications, such as
industrial drives and production of renewable energy. Main benefits of
the gland design are the grounding solution, good manufacturability and
ease of assembly. The electrical functionality of the connector was
verified by measurements.
Keywords: Variable Speed Drives, Electromagnetic Compatibility, Connectors.
Abstract - This paper illustrates the application of Adaptive Neuro-Fuzzy Inference System (ANFIS) to model Jordan transport energy demand. The ANFIS model has been developed using socio-economic and transport related indicators based on annual number of vehicles, vehicle owner level, income level, and fuel prices in Jordan. The model has been validated using testing data and has showed very accurate results of 97%. It is expected that the results of this study will be helpful in developing highly applicable and productive planning for future transport energy policies. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Energy, Transportation, ANFIS, Jordan.
Abstract -
On electrified rail line, the necessary energy for the traction of
vehicles on rail is transferred by a sliding contact copper-stainless
steel. During the functioning, the couple is submitted to severe
conditions, in more of electrical and mechanical parameters, the climate
factors and environment play an important role and determine the life
service of the couple. To understand the phenomena acting on the contact
we study the friction and wear processes of the catenary, simulated as
cable of diameter 2.6 mm, where its replacement is expensive. For this
reason, we have used the contact a pin-disc tribometer, modified in disc
U-shape frame between which cooper cable is stretched wire-disc to study
the tribological behavior of the couple. The copper cable is subjected
to tensile mechanical 110N/cm2, the rubbing disc is of steel 304 L. The
dry friction and wear of the cable are studied with the parameters:
bearing load (1-20N), sliding speed (0.25-7m/s), electrical current
(0-40A), its polarity and time. The test duration is (1-2h). The
experimental results show that these parameters have a more or less
significant effect on the tribological behavior of the couple. The
discussion of results is based on observations with optical and scanning
electronic microscopes and interfacial phenomena resulting from the
sliding contact.
Keywords: Dry Friction, Wear, Copper-Steel, Oxidation, Electrical Current.
Abstract - The
Karush-Kuhn-Tucker (KKT) approach is a well established classical method
to solve non-linear programming (NLP) optimization problems. The aim of
this work is to integrate the KKT method into the Hopfield Neural
Networks (HNN) and hence create a new algorithm, the KKT-hopfield neural
networks (KHN) for solving nonlinear optimization problems that contain
inequality constraints. In this work, the development and the testing of
the KHN algorithm was carried out. The KHN algorithm was used for
solving two engineering design problems which were; ‘optimization of the
design of a pressure vessel’ (P1) and the ‘optimization of the design of
a tension/compression spring’ (P2). The computational performance of the
KHN algorithm was then compared against the modified particle swarm
optimization (PSO) algorithm of previous work on similar engineering
problems. Comparative studies and analysis were then carried out based
on the optimized results.
Keywords: Karush-Kuhn-Tucker (KKT) Non-Linear Programming (NLP) Optimization, Hopfield Neural Networks (HNN), KKT-Hopfield Neural Networks (KHN), Engineering Design and PSO Algorithm.
Abstract - Stand-alone solar photovoltaic power systems are natural options for application in the electrification of remote areas which are outside the grid connected electricity supply systems. They represent a vast and varied range of possibilities. A standard and durable stand-alone photovoltaic system with more than 20 years life expectancy for handling household appliances in remote residential locations has been designed. This was necessitated by the fact that most rural villages are not connected to the national grid supply which has been very epileptic, unsteady and unpredicted even when available. Also, the technical overview of this system and the impact of solar irradiance on the performance of photovoltaic cells are presented. Further, the system’s design including the general load evaluation and the ampere-hour method of sizing the system and its balance-of-system components are adopted and consolidated. From the design performance, the calculated ampere-hour load was estimated at 1388.88 AH/day with a system design current of 374.92 Amps and a peak current of 232.74 Amps, while the corrected ampere-hour load was 1574.66 AH/day, respectively. These, have the capacity of derating the current at 416.58 Amps utilizing a total of 640 modules and 144 deep-charge solar photovoltaic batteries. Copyright © 2011 Praise Worthy Prize S.r.l. - All rights reserved
Keywords: Hypothetical Adaptation, Stand-Alone Photovoltaic, Resource Base Substitute, Optimal Alternative Energy Production, Remote Residential Application.
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