Abstract: Wavelength Division Multiplexing (WDM)
technology is the most promising technology for the proper
utilization of huge raw bandwidth provided by an optical fiber. One
of the key problems in implementing the all-optical WDM network is
the packet contention. This problem can be solved by several
different techniques. In time domain approach the packet contention
can be reduced by incorporating Fiber Delay Lines (FDLs) as optical
buffer in the switch architecture. Different types of buffering
architectures are reported in literatures. In the present paper a
comparative performance analysis of three most popular FDL
architectures are presented in order to obtain the best contention
resolution performance. The analysis is further extended to consider
the effect of different fiber non-linearities on the network
performance.
Abstract: In this paper, a prototype PEM fuel cell vehicle
integrated with a 1 kW air-blowing proton exchange membrane fuel
cell (PEMFC) stack as a main power sources has been developed for
a lightweight cruising vehicle. The test vehicle is equipped with a
PEM fuel cell system that provides electric power to a brushed DC
motor. This vehicle was designed to compete with industrial
lightweight vehicle with the target of consuming least amount of
energy and high performance. Individual variations in driving style
have a significant impact on vehicle energy efficiency and it is well
established from the literature. The primary aim of this study was to
assesses the power and fuel consumption of a hydrogen fuel cell
vehicle operating at three difference driving technique (i.e. 25 km/h
constant speed, 22-28 km/h speed range, 20-30 km/h speed range).
The goal is to develop the best driving strategy to maximize
performance and minimize fuel consumption for the vehicle system.
The relationship between power demand and hydrogen consumption
has also been discussed. All the techniques can be evaluated and
compared on broadly similar terms. Automatic intelligent controller
for driving prototype fuel cell vehicle on different obstacle while
maintaining all systems at maximum efficiency was used. The result
showed that 25 km/h constant speed was identified for optimal
driving with less fuel consumption.
Abstract: The research investigates the causes of unemployment
in Namibia, Nigeria and South Africa and the role of Capital
Accumulation in reducing the unemployment profile of these
economies as proposed by the post-Keynesian economics. This is
conducted through extensive review of literature on the NAIRU
models and focused on the post-Keynesian view of unemployment
within the NAIRU framework. The NAIRU (non-accelerating
inflation rate of unemployment) model has become a dominant
framework used in macroeconomic analysis of unemployment. The
study views the post-Keynesian economics arguments that capital
accumulation is a major determinant of unemployment.
Unemployment remains the fundamental socio-economic challenge
facing African economies. It has been a burden to citizens of those
economies. Namibia, Nigeria, and South Africa are great African
nations battling with high unemployment rates. The high
unemployment rate in the country led the citizens to chase away
foreigners in the country claiming that they have taken away their
jobs. The study proposes there is a strong relationship between
capital accumulation and unemployment in Namibia, Nigeria, and
South Africa, and capital accumulation is responsible for high
unemployment rates in these countries. For the economies to achieve
steady state level of employment and satisfactory level of economic
growth and development, there is need for capital accumulation to
take place. The countries in the study have been selected after a
critical research and investigations. They are selected based on the
following criteria; African economies with high unemployment rates
above 15% and have about 40% of their workforce unemployed. This
level of unemployment is the critical level of unemployment in
Africa as expressed by International Labour Organization (ILO). And
finally, the African countries experience a slow growth in their Gross
fixed capital formation. Adequate statistical measures have been
employed using a time-series analysis in the study and the results
revealed that capital accumulation is the main driver of
unemployment performance in the chosen African countries. An
increase in the accumulation of capital causes unemployment to
reduce significantly. The results of the research work will be useful
and relevant to federal governments and ministries, departments and
agencies (MDAs) of Namibia, Nigeria and South Africa to resolve
the issue of high and persistent unemployment rates in their
economies which are great burden that slows growth and
development of developing economies. Also, the result can be useful
to World Bank, African Development Bank and International Labour
Organization (ILO) in their further research and studies on how to
tackle unemployment in developing and emerging economies.
Abstract: A myriad of environmental issues face the Nigerian
industrial region, resulting from; oil and gas production, mining,
manufacturing and domestic wastes. Amidst these, much effort has
been directed by stakeholders in the Nigerian oil producing regions,
because of the impacts of the region on the wider Nigerian economy.
Although collaborative environmental management has been noted as
an effective approach in managing environmental issues, little
attention has been given to the roles and practices of stakeholders in
effecting a collaborative environmental management framework for
the Nigerian oil-producing region. This paper produces a framework
to expand and deepen knowledge relating to stakeholders aspects of
collaborative roles in managing environmental issues in the Nigeria
oil-producing region. The knowledge is derived from analysis of
stakeholders’ practices – studied through multiple case studies using
document analysis. Selected documents of key stakeholders –
Nigerian government agencies, multi-national oil companies and host
communities, were analyzed. Open and selective coding was
employed manually during document analysis of data collected from
the offices and websites of the stakeholders. The findings showed
that the stakeholders have a range of roles, practices, interests, drivers
and barriers regarding their collaborative roles in managing
environmental issues. While they have interests for efficient resource
use, compliance to standards, sharing of responsibilities, generating
of new solutions, and shared objectives; there is evidence of major
barriers and these include resource allocation, disjointed policy,
ineffective monitoring, diverse socio- economic interests, lack of
stakeholders’ commitment and limited knowledge sharing. However,
host communities hold deep concerns over the collaborative roles of
stakeholders for economic interests, particularly, where government
agencies and multi-national oil companies are involved. With these
barriers and concerns, a genuine stakeholders’ collaboration is found
to be limited, and as a result, optimal environmental management
practices and policies have not been successfully implemented in the
Nigeria oil-producing region. A framework is produced that describes
practices that characterize collaborative environmental management
might be employed to satisfy the stakeholders’ interests. The
framework recommends critical factors, based on the findings, which
may guide a collaborative environmental management in the oil
producing regions. The recommendations are designed to re-define
the practices of stakeholders in managing environmental issues in the
oil producing regions, not as something wholly new, but as an
approach essential for implementing a sustainable environmental
policy. This research outcome may clarify areas for future research as
well as to contribute to industry guidance in the area of collaborative
environmental management.
Abstract: This report examines the current state of human gait
simulator development based on the human hip joint model. This unit
will create a database of human gait types, useful for setting up and
calibrating Mechano devices, as well as the creation of new systems
of rehabilitation, exoskeletons and walking robots. The system has
many opportunities to configure the dimensions and stiffness, while
maintaining relative simplicity.
Abstract: This paper presents the development of a mobile
application for students at the Faculty of Information Technology,
Rangsit University (RSU), Thailand. RSU upgrades an enrollment
process by improving its information systems. Students can
download the RSU APP easily in order to access the RSU substantial
information. The reason of having a mobile application is to help
students to access the system regardless of time and place. The objectives of this paper include: 1. To develop an application
on iOS platform for those students at the Faculty of Information
Technology, Rangsit University, Thailand. 2. To obtain the students’
perception towards the new mobile app. The target group is those
from the freshman year till the senior year of the faculty of
Information Technology, Rangsit University. The new mobile application, called as RSU APP, is developed by
the department of Information Technology, Rangsit University. It
contains useful features and various functionalities particularly on
those that can give support to students. The core contents of the app
consist of RSU’s announcement, calendar, events, activities, and ebook.
The mobile app is developed on the iOS platform. The user
satisfaction is analyzed from the interview data from 81 interviewees
as well as a Google application like a Google form which 122
interviewees are involved. The result shows that users are satisfied
with the application as they score it the most satisfaction level at 4.67
SD 0.52. The score for the question if users can learn and use the
application quickly is high which is 4.82 SD 0.71. On the other hand,
the lowest satisfaction rating is in the app’s form, apps lists, with the
satisfaction level as 4.01 SD 0.45.
Abstract: Hydrogen produced by means of polymer electrolyte
membrane electrolyzer (PEME) is one of the most promising
methods due to clean and renewable energy source. In the process,
some energy loss due to mass transfer through a PEM is caused by
diffusion, electro-osmotic drag, and the pressure difference between
the cathode channel and anode channel. In PEME, water molecules
and ionic particles transferred between the electrodes from anode to
cathode, Extensive mixing of the hydrogen and oxygen at anode
channel due to gases cross-over must be avoided. In recent times the
consciousness of safety issue in high pressure PEME where the
oxygen mix with hydrogen at anode channel could create, explosive
conditions have generated a lot of concern. In this paper, the steady
state and simulation analysis of gases crossover in PEME on the
temperature and pressure effect are presented. The simulations have
been analysis in MATLAB based on the well-known Fick’s Law of
molecular diffusion. The simulation results indicated that as
temperature increases, there is a significant decrease in operating
voltage.
Abstract: In the past years electric mobility became part of a
public discussion. The trend to fully electrified vehicles instead of
vehicles fueled with fossil energy has notably gained momentum.
Today nearly every big car manufacturer produces and sells fully
electrified vehicles, but electrified vehicles are still not as competitive
as conventional powered vehicles. As the traction battery states the
largest cost driver, lowering its price is a crucial objective. In
addition to improvements in product and production processes a nonnegligible,
but widely underestimated cost driver of production can
be found in logistics, since the production technology is not
continuous yet and neither are the logistics systems. This paper presents an approach to evaluate cost factors on
different designs of load carrier systems. Due to numerous
interdependencies, the combination of costs factors for a particular
scenario is not transparent. This is effecting actions for cost reduction
negatively, but still cost reduction is one of the major goals for
simultaneous engineering processes. Therefore a concurrent and
phase appropriate cost valuation method is necessary to serve cost
transparency. In this paper the four phases of this cost valuation
method are defined and explained, which based upon a new approach
integrating the logistics development process in to the integrated
product and process development.
Abstract: Frozen shrimp industry plays an important role in the
development of production industry of the country. There has been a
continuing development to response the increasing demand; however,
there have been some problems in running the enterprises. The
purposes of this study are to: 1) investigate problems related to basic
factors in operating frozen shrimp industry based on the
entrepreneurs’ points of view. The enterprises involved in this study
were small and medium industry receiving Thai Frozen Foods
Association. 2) Compare the problems of the frozen shrimp industry
according to their sizes of operation in 3 provinces of the central
region Thailand. Population in this study consisted of 148 managers
from 148 frozen shrimp enterprises Thai Frozen Foods Association
which 77 were small size and 71 were medium size. The data were
analyzed to find percentage, arithmetic mean, standard deviation, and
independent sample T-test with the significant hypothesis at .05. The
results revealed that the problems of the frozen shrimp industries of
both size were in high level. The needs for government supporting
were in high level. The comparison of the problems and the basic
factors between the small and medium size enterprises showed no
statistically significant level. The problems that they mentioned
included raw materials, labors, production, marketing, and the need
for academic supporting from the government sector.
Abstract: Thermoacoustic refrigerator is a cooling device which
uses the acoustic waves to produce the cooling effect. The aim of this
paper is to explore the experimental and numerical feasibility of a
standing-wave thermoacoustic refrigerator. The effects of the stack
length, position of stack and operating frequency on the cooling
performance are carried out. The circular pore stacks are tested under
the atmospheric pressure. A low-cost loudspeaker is used as an
acoustic driver. The results show that the location of stack installed in
resonator tube has a greater effect on the cooling performance, than
the stack length and operating frequency, respectively. The
temperature difference across the ends of stack can be generated up
to 13.7°C, and the temperature of cold-end is dropped down by 5.3°C
from the ambient temperature.
Abstract: Considering the challenges of short product life cycles
and growing variant diversity, cost minimization and manufacturing
flexibility increasingly gain importance to maintain a competitive
edge in today’s global and dynamic markets. In this context, an
aerodynamic part feeding system for high-speed industrial assembly
applications has been developed at the Institute of Production
Systems and Logistics (IFA), Leibniz Universitaet Hannover. The
aerodynamic part feeding system outperforms conventional systems
with respect to its process safety, reliability, and operating speed. In
this paper, a multi-objective optimisation of the aerodynamic feeding
system regarding the orientation rate, the feeding velocity, and the
required nozzle pressure is presented.
Abstract: This research work presents the surface
thermodynamics approach to M-TB/HIV-Human sputum
interactions. This involved the use of the Hamaker coefficient
concept as a surface energetics tool in determining the interaction
processes, with the surface interfacial energies explained using van
der Waals concept of particle interactions. The Lifshitz derivation for
van der Waals forces was applied as an alternative to the contact
angle approach which has been widely used in other biological
systems. The methodology involved taking sputum samples from
twenty infected persons and from twenty uninfected persons for
absorbance measurement using a digital Ultraviolet visible
Spectrophotometer. The variables required for the computations with
the Lifshitz formula were derived from the absorbance data. The
Matlab software tools were used in the mathematical analysis of the
data produced from the experiments (absorbance values). The
Hamaker constants and the combined Hamaker coefficients were
obtained using the values of the dielectric constant together with the
Lifshitz Equation. The absolute combined Hamaker coefficients
A132abs and A131abs on both infected and uninfected sputum samples
gave the values of A132abs = 0.21631x10-21Joule for M-TB infected
sputum and Ã132abs = 0.18825x10-21Joule for M-TB/HIV infected
sputum. The significance of this result is the positive value of the
absolute combined Hamaker coefficient which suggests the existence
of net positive van der waals forces demonstrating an attraction
between the bacteria and the macrophage. This however, implies that
infection can occur. It was also shown that in the presence of HIV,
the interaction energy is reduced by 13% conforming adverse effects
observed in HIV patients suffering from tuberculosis.
Abstract: Finding the optimal 3D path of an aerial vehicle under
flight mechanics constraints is a major challenge, especially when
the algorithm has to produce real time results in flight. Kinematics
models and Pythagorian Hodograph curves have been widely used
in mobile robotics to solve this problematic. The level of difficulty
is mainly driven by the number of constraints to be saturated at the
same time while minimizing the total length of the path. In this paper,
we suggest a pragmatic algorithm capable of saturating at the same
time most of dimensioning helicopter 3D trajectories’ constraints
like: curvature, curvature derivative, torsion, torsion derivative, climb
angle, climb angle derivative, positions. The trajectories generation
algorithm is able to generate versatile complex 3D motion primitives
feasible by a helicopter with parameterization of the curvature and the
climb angle. An upper ”motion primitives’ concatenation” algorithm
is presented based. In this article we introduce a new way of designing
three-dimensional trajectories based on what we call the ”Dubins
gliding symmetry conjecture”. This extremely performing algorithm
will be soon integrated to a real-time decisional system dealing with
inflight safety issues.
Abstract: In this paper, we have reported birefringence
manipulation in regenerated high birefringent fiber Bragg grating
(RPMG) by using CO2 laser annealing method. The results indicate
that the birefringence of RPMG remains unchanged after CO2 laser
annealing followed by slow cooling process, but reduced after fast
cooling process (~5.6×10-5). After a series of annealing procedures
with different cooling rates, the obtained results show that slower the
cooling rate, higher the birefringence of RPMG. The volume, thermal
expansion coefficient (TEC) and glass transition temperature (Tg)
change of stress applying part in RPMG during cooling process are
responsible for the birefringence change. Therefore, these findings
are important to the RPMG sensor in high and dynamic temperature
environment. The measuring accuracy, range and sensitivity of
RPMG sensor is greatly affected by its birefringence value. This
work also opens up a new application of CO2 laser for fiber annealing
and birefringence modification.
Abstract: In this paper, we calculate the two-photon ionization
(TPI) cross-section for pump-probe scheme in Ag neutral cluster. The
pump photon energy is assumed to be close to the surface plasmon
(SP) energy of cluster in dielectric media. Due to this choice, the
pump wave excites collective oscillations of electrons-SP and the
probe wave causes ionization of the cluster. Since the interband
transition energy in Ag exceeds the SP resonance energy, the main
contribution into the TPI comes from the latter. The advantage of Ag
clusters as compared to the other noble metals is that the SP
resonance in silver cluster is much sharper because of peculiarities of
its dielectric function. The calculations are performed by separating
the coordinates of electrons corresponding to the collective
oscillations and the individual motion that allows taking into account
the resonance contribution of excited SP oscillations. It is shown that
the ionization cross section increases by two orders of magnitude if
the energy of the pump photon matches the surface plasmon energy
in the cluster.
Abstract: As a result of the ambiguity and complexity
surrounding anaerobic digester foaming, efforts have been made by
various researchers to understand the process of anaerobic digester
foaming so as to proffer a solution that can be universally applied
rather than site specific. All attempts ranging from experimental
analysis to comparative review of other process has not fully
explained the conditions and process of foaming in anaerobic
digester. Studying the current available knowledge on foam
formation and relating it to anaerobic digester process and operating
condition, this piece of work presents a succinct and enhanced
understanding of foaming in anaerobic digesters as well as
introducing a simple method to identify the onset of anaerobic
digester foaming based on analysis of historical data from a field
scale system.
Abstract: Broiler slaughter waste has become a major source of
pollution throughout the world. Utilization of broiler slaughter waste
by dry rendering process produced Rendered Chicken Oil (RCO), a
cheap raw material for biodiesel production and Carcass Meal a feed
ingredient for pets and fishes. Conversion of RCO into biodiesel may
open new vistas for generating wealth from waste besides controlling
the major havoc of environmental pollution. A two-step process to
convert RCO to good quality Biodiesel was invented. Acid catalysed
esterification of FFA followed by base catalysed transesterification of
triglycerides was carried out after meticulously standardizing the
methanol molar ratio, catalyst concentration, reaction temperature,
and reaction time to obtain the maximum biodiesel yield of 97.62%
and lowest glycerol yield of 6.96%. RCO biodiesel blend was tested
in a CRDI diesel engine. The results revealed that the blending of
commercial diesel with 20% RCO biodiesel (B20) lead to less engine
wear, a quieter engine and better fuel economy. The better lubricating
qualities of RCO B20 prevented over heating of engine, which
prolongs the engine life. RCO B20 can reduce the import of crude oil
and substantially reduce the engine emissions as proved by
significantly lower smoke levels, thus mitigating climatic changes.
Abstract: Highly developed technology and highly competitive
global market highlight the important role of competitive advantages
and operation performances in sustainable company operation.
Activity-Based Costing (ABC) provides accurate operation cost and
operation performance information. Rich literatures provide relevant
research with cases study on Activity-Based Costing application, but
the research on cause relationship between key success factors and its
specific outcome, such as profitability or share market are few. These
relationships provide the ways to handle the key success factors to
achieve the specific outcomes for ensuring to promote the competitive
advantages and operation performances. The main purposes of this
research are exploring the key success paths by Key Success Paths
approach which will lead the ways to apply Activity-Base Costing.
The Key Success Paths is the innovative method which is exploring
the cause relationships and explaining what are the effects of key
success factors to specific outcomes of Activity-Based Costing
implementation. The cause relationships between key success factors
and successful specific outcomes are Key Success Paths (KSPs). KSPs
are the guidelines to lead the cost management strategies to achieve the
goals of competitive advantages and operation performances. The
research findings indicate that good management system design may
affect the well outcomes of Activity-Based Costing application and
achieve to outstanding competitive advantage, operating performance
and profitability as well by KSPs exploration.
Abstract: The paper will focus on the strategic development
deriving from the evolution of the traditional courtyard spatial
organization towards a new, contemporary sustainable way of living.
New sustainable approaches that engulf the social issues, the notion
of place, the understanding of weather architecture blended together
with the bioclimatic behavior will be seen through a series of
experimental case studies in the island of Cyprus, inspired and
originated from its traditional wisdom, ranging from small scale of
living to urban interventions. Weather and nature will be seen as co-architectural authors with
architects. Furthermore, the building will be seen not as an object but
rather as a vessel of human activities. This will further enhance the
notion of merging the material and immaterial, the built and unbuilt,
subject-human, and the object-building. This eventually will enable
to generate the discussion of the understanding of the building in
relation to the place and its inhabitants, where the human topography
is more important than the material topography. The specificities of
the divided island and the dealing with sites that are in vicinity with
the diving Green Line will further trigger explorations dealing with
the regeneration issues and the social sustainability offering
unprecedented opportunities for innovative sustainable ways of
living. Opening up a discourse with premises of weather-nature, materialimmaterial,
human-material topographies in relation to the contested
sites of the borders will lead us to develop innovative strategies for a
profound, both technical and social sustainability, which fruitfully
yields to innovative living built environments, responding to the ever
changing environmental and social needs. As a starting point, a case study in Kaimakli in Nicosia, a
refurbishment with an extension of a traditional house, already
engulfs all the traditional/ vernacular wisdom of the bioclimatic
architecture. The project focusses on the direct and quite obvious
bioclimatic features such as south orientation and cross ventilation.
Furthermore, it tries to reinvent the adaptation of these parameters in
order to turn the whole house to a contemporary living environment.
In order to succeed this, evolutions of traditional architectural
elements and spatial conditions are integrated in a way that does not
only respond to some certain weather conditions, but they integrate
and blend the weather within the built environment. A series of
innovations aiming at maximum flexibility is proposed. The house
can finally be transformed into a winter enclosure, while for the most
part of the year it turns into a ‘camping’ living environment. Parallel to experimental interventions in existing traditional units,
we will proceed examining the implementation of the same
developed methodology in designing living units and complexes.
Malleable courtyard organizations that attempt to blend the
traditional wisdom with the contemporary needs for living, the
weather and nature with the built environment will be seen tested in
both horizontal and vertical developments. Social activities are seen as directly affected and forged by the
weather conditions thus generating a new social identity of people where people are directly involved and interacting with the weather.
The human actions and interaction with the built, material
environment in order to respond to weather will be seen as the result
of balancing the social with the technological sustainability, the
immaterial, and the material aspects of the living environment.
Abstract: Sweep frequency response analysis has been turning
out a powerful tool for investigation of mechanical as well as
electrical integration of transformers. In this paper various aspect of
practical application of SFRA has been studied. Open circuit and
short circuit measurement were done on different phases of high
voltage and low voltage winding. A case study was presented for the
transformer of rating 31.5 MVA for various frequency ranges. A
clear picture was presented for sub- frequency ranges for HV as well
as LV winding. The main motive of work is to investigate high
voltage short circuit response. The theoretical concept about SFRA
responses is validated with expert system software results.