Abstract: This paper considers the integration of assembly
operations and product structure to Cellular Manufacturing System
(CMS) design so that to correct the drawbacks of previous researches
in the literature. For this purpose, a new mathematical model is
developed which dedicates machining and assembly operations to
manufacturing cells while the objective function is to minimize the
intercellular movements resulting due to both of them. A
linearization method is applied to achieve optimum solution through
solving aforementioned nonlinear model by common programming
language such as Lingo. Then, using different examples and
comparing the results, the importance of integrating assembly
considerations is demonstrated.
Abstract: The study of the generated defects on manufactured
parts shows the difficulty to maintain parts in their positions during
the machining process and to estimate them during the pre-process
plan. This work presents a contribution to the development of 3D
models for the optimization of the manufacturing tolerances. An
experimental study allows the measurement of the defects of part
positioning for the determination of ε and the choice of an optimal
setup of the part. An approach of 3D tolerance based on the small
displacements method permits the determination of the
manufacturing errors upstream. A developed tool, allows an
automatic generation of the tolerance intervals along the three axes.
Abstract: Preparation and negotiation of innovative and future
projects can be characterized as a strategic-type decision situation,
involving many uncertainties and an unpredictable environment.
We will focus in this paper on the bidding process. It includes cooperative
and strategic decisions.
Our approach for bidding process knowledge capitalization is
aimed at information management in project-oriented organizations,
based on the MUSIC (Management and Use of Co-operative
Information Systems) model.
We will show how to capitalize the company strategic knowledge
and also how to organize the corporate memory. The result of the
adopted approach is improvement of corporate memory quality.
Abstract: In this researcha particle swarm optimization (PSO)
algorithm is proposedfor no-wait flowshopsequence dependent
setuptime scheduling problem with weighted earliness-tardiness
penalties as the criterion (|,
|Σ
"
).The
smallestposition value (SPV) rule is applied to convert the continuous
value of position vector of particles in PSO to job permutations.A
timing algorithm is generated to find the optimal schedule and
calculate the objective function value of a given sequence in PSO
algorithm. Twodifferent neighborhood structures are applied to
improve the solution quality of PSO algorithm.The first one is based
on variable neighborhood search (VNS) and the second one is a
simple one with invariable structure. In order to compare the
performance of two neighborhood structures, random test problems
are generated and solved by both neighborhood
approaches.Computational results show that the VNS algorithmhas
better performance than the other one especially for the large sized
problems.
Abstract: Complex systems are composed of several plain interacting independent entities. Interaction between these entities creates a unified behavior at the global level that cannot be predicted by examining the behavior of any single individual component of the system. In this paper we consider a welded frame of an automobile trailer as a real example of Complex Technical Systems, The purpose of this paper is to introduce a Statistical method for predicting the life cycle of complex technical systems. To organize gathering of primary data for modeling the life cycle of complex technical systems an “Automobile Trailer Frame" were used as a prototype in this research. The prototype represents a welded structure of several pieces. Both information flows underwent a computerized analysis and classification for the acquisition of final results to reach final recommendations for improving the trailers structure and their operational conditions.
Abstract: This research investigates risk factors for defective products in autoparts factories. Under a Bayesian framework, a generalized linear mixed model (GLMM) in which the dependent variable, the number of defective products, has a Poisson distribution is adopted. Its performance is compared with the Poisson GLM under a Bayesian framework. The factors considered are production process, machines, and workers. The products coded RT50 are observed. The study found that the Poisson GLMM is more appropriate than the Poisson GLM. For the production Process factor, the highest risk of producing defective products is Process 1, for the Machine factor, the highest risk is Machine 5, and for the Worker factor, the highest risk is Worker 6.
Abstract: Model Predictive Control has been previously applied
to supply chain problems with promising results; however hitherto
proposed systems possessed no information on future demand. A
forecasting methodology will surely promote the efficiency of
control actions by providing insight on the future. A complete supply
chain management framework that is based on Model Predictive
Control (MPC) and Time Series Forecasting will be presented in this
paper. The proposed framework will be tested on industrial data in
order to assess the efficiency of the method and the impact of
forecast accuracy on overall control performance of the supply chain.
To this end, forecasting methodologies with different characteristics
will be implemented on test data to generate forecasts that will serve
as input to the Model Predictive Control module.
Abstract: Adhesion strength of exterior or interior coating of
steel pipes is too important. Increasing of coating adhesion on
surfaces can increase the life time of coating, safety factor of
transmitting line pipe and decreasing the rate of corrosion and costs.
Preparation of steel pipe surfaces before doing the coating process is
done by shot and grit blasting. This is a mechanical way to do it.
Some effective parameters on that process, are particle size of
abrasives, distance to surface, rate of abrasive flow, abrasive physical
properties, shapes, selection of abrasive, kind of machine and its
power, standard of surface cleanness degree, roughness, time of
blasting and weather humidity. This search intended to find some
better conditions which improve the surface preparation, adhesion
strength and corrosion resistance of coating. So, this paper has
studied the effect of varying abrasive flow rate, changing the
abrasive particle size, time of surface blasting on steel surface
roughness and over blasting on it by using the centrifugal blasting
machine. After preparation of numbers of steel samples (according to
API 5L X52) and applying epoxy powder coating on them, to
compare strength adhesion of coating by Pull-Off test. The results
have shown that, increasing the abrasive particles size and flow rate,
can increase the steel surface roughness and coating adhesion
strength but increasing the blasting time can do surface over blasting
and increasing surface temperature and hardness too, change,
decreasing steel surface roughness and coating adhesion strength.
Abstract: There is a growing body of evidence to support the
proposition of product take back for remanufacturing particularly
within the context of Extended Producer Responsibility (EPR).
Remanufacturing however presents challenges unlike that of
traditional manufacturing environments due to its high levels of
uncertainty which may further distract organizations from
considering its potential benefits. This paper presents a novel
modeling approach for evaluating the uncertainty of part failures
within the remanufacturing process and its impact on economic and
environmental performance measures. This paper presents both the
theoretical modeling approach and an example of its use in
application.
Abstract: Conventional industrial monitoring systems are
tedious, inefficient and the at times integrity of the data is
unreliable. The objective of this system is to monitor industrial
processes specifically the fluid level which will measure the
instantaneous fluid level parameter and respond by text
messaging the exact value of the parameter to the user when
being enquired by a privileged access user. The development of
the embedded program code and the circuit for fluid level
measuring are discussed as well. Suggestions for future
implementations and efficient remote monitoring works are
included.
Abstract: Industrial surveys shows that manufacturing
companies define the qualities of thermal removing process based on
the dimension and physical appearance of the cutting material
surface. Therefore, the roughness of the surface area of the material
cut by the plasma arc cutting process and the rate of the removed
material by the manual plasma arc cutting machine was importantly
considered. Plasma arc cutter Selco Genesis 90 was used to cut
Standard AISI 1017 Steel of 200 mm x100 mm x 6 mm manually
based on the selected parameters setting. The material removal rate
(MRR) was measured by determining the weight of the specimens
before and after the cutting process. The surface roughness (SR)
analysis was conducted using Mitutoyo CS-3100 to determine the
average roughness value (Ra). Taguchi method was utilized to
achieve optimum condition for both outputs studied. The
microstructure analysis in the region of the cutting surface is
performed using SEM. The results reveal that the SR values are
inversely proportional to the MRR values. The quality of the surface
roughness depends on the dross peak that occurred after the cutting
process.
Abstract: Development of intelligent assembly cell conception includes new solution kind of how to create structures of automated and flexible assembly system. The current trend of the final product quality increasing is affected by time analysis of the entire manufacturing process. The primary requirement of manufacturing is to produce as many products as soon as possible, at the lowest possible cost, but of course with the highest quality. Such requirements may be satisfied only if all the elements entering and affecting the production cycle are in a fully functional condition. These elements consist of sensory equipment and intelligent control elements that are essential for building intelligent manufacturing systems. Intelligent behavior of the system as the control system will repose on monitoring of important parameters of the system in the real time. Intelligent manufacturing system itself should be a system that can flexibly respond to changes in entering and exiting the process in interaction with the surroundings.
Abstract: Theory of Constraints has been emerging as an
important tool for optimization of manufacturing/service systems.
Goldratt in his first book “ The Goal " gave the introduction on
Theory of Constraints and its applications in a factory scenario. A
large number of production managers around the globe read this book
but only a few could implement it in their plants because the book did
not explain the steps to implement TOC in the factory. To overcome
these limitations, Goldratt wrote this book to explain TOC, DBR and
the method to implement it. In this paper, an attempt has been made
to summarize the salient features of TOC and DBR listed in the book
and the correct approach to implement TOC in a factory setting. The
simulator available along with the book was actually used by the
authors and the claim of Goldratt regarding the use of DBR and
Buffer management to ease the work of production managers was
tested and was found to be correct.
Abstract: In this paper, an inventory model with finite and
constant replenishment rate, price dependant demand rate, time
value of money and inflation, finite time horizon, lead time and
exponential deterioration rate and with the objective of maximizing
the present worth of the total system profit is developed. Using a
dynamic programming based solution algorithm, the optimal
sequence of the cycles can be found and also different optimal
selling prices, optimal order quantities and optimal maximum
inventories can be obtained for the cycles with unequal lengths,
which have never been done before for this model. Also, a
numerical example is used to show accuracy of the solution
procedure.
Abstract: This paper presents the development of low cost Nano membrane fabrication system. The system is specially designed for anodic aluminum oxide membrane. This system is capable to perform the processes such as anodization and electro-polishing. The designed machine was successfully tested for 'mild anodization' (MA) for 48 hours and 'hard anodization' (HA) for 3 hours at constant 0oC. The system is digitally controlled and guided for temperature maintenance during anodization and electro-polishing. The total cost of the developed machine is 20 times less than the multi-cooling systems available in the market which are generally used for this purpose.
Abstract: The paper outlines the drivers behind the movement
from products to solutions in the Hi-Tech Business-to-Business
markets. The paper lists out the challenges in enabling the
transformation from products to solutions and also attempts to explore
strategic and operational recommendations based on the authors-
factual experiences with Japanese Hi-tech manufacturing
organizations. Organizations in the Hi-Tech Business-to-Business
markets are increasingly being compelled to move to a solutions model
from the conventional products model. Despite the added complexity
of solutions, successful technology commercialization can be achieved
by making prudent choices in defining a relevant solutions model, by
backing the solution model through appropriate organizational design,
and by overhauling the new product development process and
supporting infrastructure.
Abstract: A cognitive collaborative reinforcement learning
algorithm (CCRL) that incorporates an advisor into the learning
process is developed to improve supervised learning. An autonomous
learner is enabled with a self awareness cognitive skill to decide
when to solicit instructions from the advisor. The learner can also
assess the value of advice, and accept or reject it. The method is
evaluated for robotic motion planning using simulation. Tests are
conducted for advisors with skill levels from expert to novice. The
CCRL algorithm and a combined method integrating its logic with
Clouse-s Introspection Approach, outperformed a base-line fully
autonomous learner, and demonstrated robust performance when
dealing with various advisor skill levels, learning to accept advice
received from an expert, while rejecting that of less skilled
collaborators. Although the CCRL algorithm is based on RL, it fits
other machine learning methods, since advisor-s actions are only
added to the outer layer.
Abstract: Due to today-s turbulent environment, manufacturing resources, particularly in assembly, must be reconfigured frequently. These reconfigurations are caused by various, partly cyclic, influencing factors. Hence, it is important to evaluate the innovation ability - the capability of resources to implement innovations quickly and efficiently without large expense - of manufacturing resources. For this purpose, a new methodology is presented in this article. Within the methodology, design structure matrices and graph theory are used. The results of the methodology include different indices to evaluate the innovation ability of the manufacturing resources. Due to the cyclicity of the influencing factors, the methodology can be used to synchronize the realization of adaptations.
Abstract: The intention of this study to design the probability optimized sewing sack-s workstation based on ergonomics for productivity improvement and decreasing musculoskeletal disorders. The physical dimensions of two workers were using to design the new workstation. The physical dimensions are (1) sitting height, (2) mid shoulder height sitting, (3) shoulder breadth, (4) knee height, (5) popliteal height, (6) hip breadth and (7) buttock-knee length. The 5th percentile of buttock knee length sitting (51 cm), the 50th percentile of mid shoulder height sitting (62 cm) and the 95th percentile of popliteal height (43 cm) and hip breadth (45 cm) applied to design the workstation for sewing sack-s operator and the others used to adjust the components of this workstation. The risk assessment by RULA before and after using the probability optimized workstation were 7 and 7 scores and REBA scores were 11 and 5, respectively. Body discomfort-abnormal index was used to assess muscle fatigue of operators before adjustment workstation found that neck muscles, arm muscles area, muscles on the back and the lower back muscles fatigue. Therefore, the extension and flexion exercise was applied to relief musculoskeletal stresses. The workers exercised 15 minutes before the beginning and the end of work for 5 days. After that, the capability of flexion and extension muscles- workers were increasing in 3 muscles (arm, leg, and back muscles).
Abstract: The design of technological procedures for
manufacturing certain products demands the definition and
optimization of technological process parameters. Their
determination depends on the model of the process itself and its
complexity. Certain processes do not have an adequate mathematical
model, thus they are modeled using heuristic methods. First part of
this paper presents a state of the art of using soft computing
techniques in manufacturing processes from the perspective of
applicability in modern CAx systems. Methods of artificial
intelligence which can be used for this purpose are analyzed. The
second part of this paper shows some of the developed models of
certain processes, as well as their applicability in the actual
calculation of parameters of some technological processes within the
design system from the viewpoint of productivity.