Abstract: In sheet metal forming process, raw material
mechanical properties are important parameters. This paper is to
compare the wall’s incline angle or formability of SS 400 steel and
SUS 304 stainless steel in single point incremental forming. The two
materials are ferrous base alloyed, which have the different unit cell,
mechanical property and chemical composition. They were forming
into cone shape specimens having 100 mm diameter with different
wall’s incline angle: 90o, 75o and 60o. The investigation was
continued until the specimens formed surface facture. The
experimental result showed that the smaller the wall incline angle
higher the formability with the both materials. The formability limit
of the ferrous base alloy was approx. 60o wall’s incline angle. By
nature, SS 400 has higher formability than SUS 304. This result can
be used as the initial data in designing the single point incremental
forming parts.
Abstract: The Lean Environmental Management Integration
System (LEMIS) framework development is integration between lean
core element and ISO 14001. The curiosity on the relationship
between continuous improvement and sustainability of lean
implementation has influenced this study toward LEMIS.
Characteristic of ISO 14001 standard clauses and core elements of
lean principles are explored from past studies and literature reviews.
Survey was carried out on ISO 14001 certified companies to examine
continual improvement by implementing the ISO 14001 standard.
The study found that there is a significant and positive relationship
between Lean Principles: value, value stream, flow, pull and
perfection with the ISO 14001 requirements. LEMIS is significant to
support the continuous improvement and sustainability. The
integration system can be implemented to any manufacturing
company. It gives awareness on the importance on why organizations
need to sustain its environmental management system. In the
meantime, the lean principle can be adapted in order to streamline
daily activities of the company. Throughout the study, it had proven
that there is no sacrifice or trade-off between lean principles with ISO
14001 requirements. The framework developed in the study can be
further simplified in the future, especially the method of crossing
each sub requirements of ISO 14001 standard with the core elements
of Lean principles in this study.
Abstract: Yttrium oxide (Y2O3) films have been successfully
deposited with yttrium-ethylenediamine tetraacetic acid (EDTA·Y·H)
complexes prepared by various milling techniques. The effects of the
properties of the EDTA·Y·H complex on the properties of the
deposited Y2O3 films have been analyzed. Seven different types of the
raw EDTA·Y·H complexes were prepared by various commercial
milling techniques such as ball milling, hammer milling, commercial
milling, and mortar milling. The milled EDTA·Y·H complexes
exhibited various particle sizes and distributions, depending on the
milling method. Furthermore, we analyzed the crystal structure,
morphology and elemental distribution profile of the metal oxide films
deposited on stainless steel substrate with the milled EDTA·Y·H
complexes. Depending on the milling technique, the flow properties of
the raw powders differed. The X-ray diffraction pattern of all the
samples revealed the formation of Y2O3 crystalline phase, irrespective
of the milling technique. Of all the different milling techniques, the
hammer milling technique is considered suitable for fabricating dense
Y2O3 films.
Abstract: Violet Sr–Al–O:Eu2+ phosphor particles were
synthesized from a metal–ethylenediaminetetraacetic acid (EDTA)
solution of Sr, Al, Eu, and particulate alumina via spray drying and
sintering in a reducing atmosphere. The crystal structures and emission
properties at 85–300 K were investigated. The composition of the
violet Sr–Al–O:Eu2+ phosphor particles was determined from various
Sr–Al–O:Eu2+ phosphors by their emission properties’ dependence
on temperature. The highly crystalline SrAl12O19:Eu2+ emission phases
were confirmed by their crystallite sizes and the activation energies for
the 4f5d–8S7/2 transition of the Eu2+ ion. These results showed that the
material identification for the violet Sr–Al–O:Eu2+ phosphor was
accomplished by the low-temperature luminescence measurements.
Abstract: In this paper the CVA computation of interest rate
swap is presented based on its rating. Rating and probability default
given by Moody’s Investors Service are used to calculate our CVA
for a specific swap with different maturities. With this computation
the influence of rating variation can be shown on CVA. Application
is made to the analysis of Greek CDS variation during the period of
Greek crisis between 2008 and 2011. The main point is the
determination of correlation between the fluctuation of Greek CDS
cumulative value and the variation of swap CVA due to change of
rating.
Abstract: There are a variety of reference current identification
methods, for the shunt active power filter (SAPF), such as the
instantaneous active and reactive power, the instantaneous active and
reactive current and the synchronous detection method are evaluated
and compared under ideal, non sinusoidal and unbalanced voltage
conditions. The SAPF performances, for the investigated
identification methods, are tested for a non linear load. The
simulation results, using Matlab Power System Blockset Toolbox
from a complete structure, are presented and discussed.
Abstract: Powder metallurgy (P/M) is the only economic way to
produce porous parts/products. P/M can produce near net shape parts
hence reduces wastage of raw material and energy, avoids various
machining operations. The most vital use of P/M is in production of
metallic filters and self lubricating bush bearings and siding surfaces.
The porosity of the part can be controlled by varying compaction
pressure, sintering temperature and composition of metal powder
mix. The present work is aimed for experimental analysis of friction
and wear properties of self lubricating copper and tin bush bearing.
Experimental results confirm that wear rate of sintered component
is lesser for components having 10% tin by weight percentage. Wear
rate increases for high tin percentage (experimented for 20% tin and
30% tin) at same sintering temperature. Experimental results also
confirms that wear rate of sintered component is also dependent on
sintering temperature, soaking period, composition of the preform,
compacting pressure, powder particle shape and size.
Interfacial friction between die and punch, between inter powder
particles, between die face and powder particle depends on
compaction pressure, powder particle size and shape, size and shape
of component which decides size & shape of die & punch, material of
die & punch and material of powder particles.
Abstract: The purpose of this work is examining the multiproduct
multi-stage in a battery production line. To improve the
performances of an assembly production line by determine the
efficiency of each workstation. Data collected from every
workstation. The data are throughput rate, number of operator, and
number of parts that arrive and leaves during part processing. Data
for the number of parts that arrives and leaves are collected at least at
the amount of ten samples to make the data is possible to be analyzed
by Chi-Squared Goodness Test and queuing theory. Measures of this
model served as the comparison with the standard data available in
the company. Validation of the task time value resulted by comparing
it with the task time value based on the company database. Some
performance factors for the multi-product multi-stage in a battery
production line in this work are shown.
The efficiency in each workstation was also shown. Total
production time to produce each part can be determined by adding
the total task time in each workstation. To reduce the queuing time
and increase the efficiency based on the analysis any probably
improvement should be done. One probably action is by increasing
the number of operators how manually operate this workstation.
Abstract: Many problems in science and engineering field require
the solution of shifted linear systems with multiple right hand
sides and multiple shifts. To solve such systems efficiently, the
implicitly restarted global GMRES algorithm is extended in this
paper. However, the shift invariant property could no longer hold over
the augmented global Krylov subspace due to adding the harmonic
Ritz matrices. To remedy this situation, we enforce the collinearity
condition on the shifted system and propose shift implicitly restarted
global GMRES. The new method not only improves the convergence
but also has a potential to simultaneously compute approximate
solution for the shifted systems using only as many matrix vector
multiplications as the solution of the seed system requires. In
addition, some numerical experiments also confirm the effectiveness
of our method.
Abstract: This research work is concerned with the life cycle
assessment (LCA) of an expressway, as well as its infrastructure, in
Thailand. The life cycle of an expressway encompasses the raw
material acquisition phase, the construction phase, the use or service
phase, the rehabilitation phase, and finally the demolition and
disposal phase. The LCA in this research was carried out using CML
baseline 2000 and in accordance with the ISO 14040 standard. A
functional unit refers to transportation of one person over one
kilometer of a 3-lane expressway with a 50-year lifetime. This
research has revealed that the construction phase produced the largest
proportion of the environmental impact (81.46%), followed by the
service, rehabilitation, demolition and disposal phases and
transportation at 11.97%, 3.72% 0.33% and 2.52%, respectively. For
the expressway under study, the total carbon footprint over its
lifetime is equivalent to 245,639 tons CO2-eq per 1 kilometer
functional unit, with the phases of construction, service,
rehabilitation, demolition and disposal and transportation
contributing 153,690; 73,773; 3693, 755 and 13,728 tons CO2-eq,
respectively. The findings could be adopted as a benchmark against
which the environmental impacts of future similar projects can be
measured.
Abstract: Due to the determination of the pollution status of
fresh resources in the Egyptian territorial waters is very important for
public health; this study was carried out to reveal the levels of heavy
metals in the shellfish and their environment and its relation to the
highly developed industrial activities in those areas. A total of 100
shellfish samples from the Rosetta, Edku, El-Maadiya, Abo-Kir and
El-Max coasts [10 crustaceans (shrimp) and 10 mollusks (oysters)]
were randomly collected from each coast. Additionally, 10 samples
from both the water and the sediment were collected from each coast.
Each collected sample was analyzed for cadmium, chromium,
copper, lead and zinc residues using a Perkin Elmer atomic
absorption spectrophotometer (AAS). The results showed that the
levels of heavy metals were higher in the water and sediment from
Abo-Kir. The heavy metal levels decreased successively for the
Rosetta, Edku, El-Maadiya, and El-Max coasts, and the
concentrations of heavy metals, except copper and zinc, in shellfish
exhibited the same pattern. For the concentration of heavy metals in
shellfish tissue, the highest was zinc and the concentrations decreased
successively for copper, lead, chromium and cadmium for all coasts,
except the Abo-Kir coast, where the chromium level was highest and
the other metals decreased successively for zinc, copper, lead and
cadmium. In Rosetta, chromium was higher only in the mollusks,
while the level of this metal was lower in the crustaceans; this trend
was observed at the Edku, El-Maadiya and El-Max coasts as well.
Herein, we discuss the importance of such contamination for public
health and the sources of shellfish contamination with heavy metals.
We suggest measures to minimize and prevent these pollutants in the
aquatic environment and, furthermore, how to protect humans from
excessive intake.
Abstract: Frequency stability of microgrids under islanded
operation attracts particular attention recently. A new cooperative
frequency control strategy based on centralized multi-agent system
(CMAS) is proposed in this study. Based on this strategy, agents sent
data and furthermore each component has its own to center operating
decisions (MGCC).After deciding on the information, they are
returned. Frequency control strategies include primary and secondary
frequency control and disposal of multi-stage load in which this study
will also provide a method and algorithm for load shedding. This
could also be a big problem for the performance of micro-grid in
times of disaster. The simulation results show the promising
performance of the proposed structure of the controller based on
multi agent systems.
Abstract: In this work, a Multi-Level Artificial Bee Colony
(called MLABC) for optimizing numerical test functions is presented.
In MLABC, two species are used. The first species employs n
colonies where each of them optimizes the complete solution vector.
The cooperation between these colonies is carried out by exchanging
information through a leader colony, which contains a set of elite
bees. The second species uses a cooperative approach in which the
complete solution vector is divided to k sub-vectors, and each of
these sub-vectors is optimized by a colony. The cooperation between
these colonies is carried out by compiling sub-vectors into the
complete solution vector. Finally, the cooperation between two
species is obtained by exchanging information. The proposed
algorithm is tested on a set of well-known test functions. The results
show that MLABC algorithm provides efficiency and robustness to
solve numerical functions.
Abstract: This paper proposes the designing direct adaptive
neural controller to apply for a class of a nonlinear pendulum
dynamic system. The radial basis function (RBF) neural adaptive
controller is robust in presence of external and internal uncertainties.
Both the effectiveness of the controller and robustness against
disturbances are importance of this paper. The simulation results
show the promising performance of the proposed controller.
Abstract: The use of mobile phones is growing tremendously all
over the world. In Tanzania there are a number of operators licensed
by Tanzania Communications Regulatory Authority (TCRA) aiming
at attracting customers into their networks. So far
telecommunications market competition has been very stiff. Various
measures are being taken by mobile operators to survive in the
market. Such measure include introducing of different air time
bundles on daily, weekly and monthly at lower tariffs. Other
measures include the introduction of normal tariff, tourist package
and one network. Despite of all these strategies, there is a dynamic
competition in the market which needs to be explored. Some
influences which attract customers to choose a certain mobile
operator are of particular interest. This paper is investigating if the
network effects and Quality of Services (QoS) influence mobile
customers in selection of their mobile network operators. Seventy
seven students from high learning institutions in Dodoma
Municipality in Tanzania participated in responding to prepared
questionnaires. The data was analyzed using Statistical Package for
Social Science (SPSS) Software. The results indicate that, network
coverage does influence customers in selection of mobile operators.
In addition, this paper proposes further research in some areas
especially where the study came up with different findings from what
the theory has in place.
Abstract: Applied industrial engineering is concerned with
imparting employable skills to improve the productivity for current
situation of products and services. The purpose of this case study is to
present the results of an initial research study conducted to identify
the desired professional characteristics of an industrial engineer with
an undergraduate degree and the emerging topic areas that should be
incorporated into the curriculum to prepare industrial engineering
(IE) graduates for the future workforce. Conclusions and
recommendations for applied industrial engineering syllabus have
been gathered and reported below. A two-pronged approach was
taken which included a method of benchmarking by comparing the
applied industrial engineering curricula of various universities and an
industry survey to identify job market requirements. This
methodology produced an analysis of the changing nature of
industrial engineering from learning to practical education. A
curriculum study for engineering is a relatively unexplored area of
research in the Middle East, much less for applied industrial
engineering. This work is an effort to bridge the gap between
theoretical study in the classroom and the real world work
applications in the industrial and service sectors.
Abstract: Dissimilar joining of Titanium and Aluminum thin
sheets has potential applications in aerospace and automobile
industry which can reduce weight and cost and improve strength,
corrosion resistance and high temperature properties. However
successful welding of Titanium/Aluminium sheets is of challenge due
to differences in physical, chemical and metallurgical properties
between the two. This paper describes research results of Laser Beam
Welding (LBW) of Ti/Al thin sheets in which many researchers have
recently performed and critically reviewed from different
perspectives. Also some of notable works in the field of laser welding
with changes in mechanical properties, crack propagation, diffusion
behavior, chemical potential, interfacial reaction and the
microstructure are reported.
Abstract: Laser beam welding is an important joining technique
for Titanium/Aluminum thin sheet alloys with their increasing
applications in aerospace, aircraft, automotive, electronics and other
industries. In this paper the research and progress in laser welding of
Ti/Al thin sheets are critically reviewed from different perspectives.
Some important aspects such as microstructure, metallurgical defects
and mechanical properties in weldments are discussed. Also the
recent progress in laser welding of Ti/Al dissimilar thin sheets to
provide a basis for further research work is reported.
Abstract: Laser beam welding for the dissimilar Titanium and
Aluminium thin sheets is an emerging area which is having wider
applications in aerospace, aircraft, automotive, electronics and in
other industries due to its high speed, non-contact, precision with low
heat effects, least welding distortion, low labor costs and convenient
operation. Laser beam welding of dissimilar metal combinations are
increasingly demanded due to high energy densities with small fusion
and heat affected zones. Furthermore, no filler or electrode material is
required and contamination of weld is also very small. The present
study is to reviews the influence of different parameters like laser
power, welding speed, power density, beam diameter, focusing
distance and type of shielding gas on the mechanical properties of
dissimilar metal combinations like SS/Al, Cu/Al and Ti/Al focusing
on aluminum to other materials. Research findings reveal that Ti/Al
combination gives better metallurgical and mechanical properties
than other combinations such as SS/Al and Cu/Al.
Abstract: Artificial Immune Systems (AIS), inspired by the
human immune system, are algorithms and mechanisms which are
self-adaptive and self-learning classifiers capable of recognizing and
classifying by learning, long-term memory and association. Unlike
other human system inspired techniques like genetic algorithms and
neural networks, AIS includes a range of algorithms modeling on
different immune mechanism of the body. In this paper, a mechanism
of a human immune system based on apoptosis is adopted to build an
Intrusion Detection System (IDS) to protect computer networks.
Features are selected from network traffic using Fisher Score. Based
on the selected features, the record/connection is classified as either
an attack or normal traffic by the proposed methodology. Simulation
results demonstrates that the proposed AIS based on apoptosis
performs better than existing AIS for intrusion detection.