Abstract: Fracture in hot precision forging of engine valves was
investigated in this paper. The entire valve forging procedure was
described and the possible cause of the fracture was proposed. Finite
Element simulation was conducted for the forging process, with
commercial Finite Element code DEFORMTM. The effects of
material properties, the effect of strain rate and temperature were
considered in the FE simulation. Two fracture criteria were discussed
and compared, based on the accuracy and reliability of the FE
simulation results. The selected criterion predicted the fracture
location and shows the trend of damage increasing with good
accuracy, which matches the experimental observation. Additional
modification of the punch shapes was proposed to further reduce the
tendency of fracture in forging. Finite Element comparison shows a
great potential of such application in the mass production.
Abstract: In this work, we study the behavior of introducing
atomic size vacancy in a graphene nanoribbon superlattice. Our
investigations are based on the density functional theory (DFT) with
the Local Density Approximation in Atomistix Toolkit (ATK). We
show that, in addition to its shape, the position of vacancy has a
major impact on the electrical properties of a graphene nanoribbon
superlattice. We show that the band gap of an armchair graphene
nanoribbon may be tuned by introducing an appropriate periodic
pattern of vacancies. The band gap changes in a zig-zag manner
similar to the variation of band gap of a graphene nanoribbon by
changing its width.
Abstract: The study is a review of the literature concerning the
consequences of non-standard monetary policy, which are used by
central banks during unconventional periods, threatening banking
sector instability. In particular, the attention was paid to the effects of
non-standard monetary policy tools for financial markets. However,
the empirical evidence about their effects and real consequences for
financial markets is still not final. The main aim of the study is to
survey consequences of standard and non-standard monetary policy
instruments, implemented during the global financial crisis in the
United States, United Kingdom and euro area, with particular
attention to the results for the stabilization of global financial
markets. The study consists mainly of the empirical review,
indicating the impact of the implementation of these tools for
financial markets. The following research methods were used in the
study: literature studies, including domestic and foreign literature,
cause and effect analysis and statistical analysis.
Abstract: Motion Tracking and Stereo Vision are complicated,
albeit well-understood problems in computer vision. Existing
softwares that combine the two approaches to perform stereo motion
tracking typically employ complicated and computationally expensive
procedures. The purpose of this study is to create a simple and
effective solution capable of combining the two approaches. The
study aims to explore a strategy to combine the two techniques
of two-dimensional motion tracking using Kalman Filter; and depth
detection of object using Stereo Vision. In conventional approaches
objects in the scene of interest are observed using a single camera.
However for Stereo Motion Tracking; the scene of interest is
observed using video feeds from two calibrated cameras. Using two
simultaneous measurements from the two cameras a calculation for
the depth of the object from the plane containing the cameras is made.
The approach attempts to capture the entire three-dimensional spatial
information of each object at the scene and represent it through a
software estimator object. In discrete intervals, the estimator tracks
object motion in the plane parallel to plane containing cameras and
updates the perpendicular distance value of the object from the plane
containing the cameras as depth. The ability to efficiently track
the motion of objects in three-dimensional space using a simplified
approach could prove to be an indispensable tool in a variety of
surveillance scenarios. The approach may find application from high
security surveillance scenes such as premises of bank vaults, prisons
or other detention facilities; to low cost applications in supermarkets
and car parking lots.
Abstract: Chemical Reaction Optimization (CRO) is an
optimization metaheuristic inspired by the nature of chemical
reactions as a natural process of transforming the substances from
unstable to stable states. Starting with some unstable molecules with
excessive energy, a sequence of interactions takes the set to a state of
minimum energy. Researchers reported successful application of the
algorithm in solving some engineering problems, like the quadratic
assignment problem, with superior performance when compared with
other optimization algorithms. We adapted this optimization
algorithm to the Printed Circuit Board Drilling Problem (PCBDP)
towards reducing the drilling time and hence improving the PCB
manufacturing throughput. Although the PCBDP can be viewed as
instance of the popular Traveling Salesman Problem (TSP), it has
some characteristics that would require special attention to the
transactions that explore the solution landscape. Experimental test
results using the standard CROToolBox are not promising for
practically sized problems, while it could find optimal solutions for
artificial problems and small benchmarks as a proof of concept.
Abstract: Fugitive particulate matter (PM) is a major source of
airborne pollution in the Middle East countries. The meteorological
conditions and topography of the area makes it highly susceptible to
wind-blown particles which raise many air quality concerns. Air
quality tools such as field monitoring, emission factors and dispersion
modeling have been used in previous research studies to analyze the
release and impacts of fugitive PM in the region. However, these
tools have been originally developed based on experiments made for
European and North American regions. In this work, an experimental
campaign was conducted on April-May 2014 in a construction site in
Doha city, Qatar. The ultimate goal is to evaluate the applicability of
the existing emission factors for construction sites in dry and arid
areas like the Middle East.
Abstract: Proof of controlling crack width is a basic condition
for securing suitable performance in serviceability limit state. The
cracking in concrete can occur at any time from the casting of time to
the years after the concrete has been set in place. Most codes struggle
with offering procedure for crack width calculation. There is lack in
availability of design charts for designers to compute crack width
with ease. The focus of the study is to utilize design charts and
parametric equations in calculating crack width with minimum error.
The paper contains a simplified procedure to calculate crack width
for reinforced concrete (RC) sections subjected to bending with axial
tensile force following the guidelines of Euro code [DS EN-1992-1-1
& DS EN-1992-1-2]. Numerical examples demonstrate the
application of the suggested procedure. Comparison with parallel
analytical tools supports the validity of result and show the
percentage deviation of crack width in both the procedures. The
technique is simple, user friendly and ready to evolve for a greater
spectrum of section sizes and materials.
Abstract: Web-based Cognitive Writing Instruction (WeCWI)’s
contribution towards language development can be divided into
linguistic and non-linguistic perspectives. In linguistic perspective,
WeCWI focuses on the literacy and language discoveries, while the
cognitive and psychological discoveries are the hubs in non-linguistic
perspective. In linguistic perspective, WeCWI draws attention to free
reading and enterprises, which are supported by the language
acquisition theories. Besides, the adoption of process genre approach
as a hybrid guided writing approach fosters literacy development.
Literacy and language developments are interconnected in the
communication process; hence, WeCWI encourages meaningful
discussion based on the interactionist theory that involves input,
negotiation, output, and interactional feedback. Rooted in the elearning
interaction-based model, WeCWI promotes online
discussion via synchronous and asynchronous communications,
which allows interactions happened among the learners, instructor,
and digital content. In non-linguistic perspective, WeCWI highlights
on the contribution of reading, discussion, and writing towards
cognitive development. Based on the inquiry models, learners’
critical thinking is fostered during information exploration process
through interaction and questioning. Lastly, to lower writing anxiety,
WeCWI develops the instructional tool with supportive features to
facilitate the writing process. To bring a positive user experience to
the learner, WeCWI aims to create the instructional tool with
different interface designs based on two different types of perceptual
learning style.
Abstract: Passing the entrance exam to a university is a major
step in one's life. University entrance exam commonly known as
Kankor is the nationwide entrance exam in Afghanistan. This
examination is prerequisite for all public and private higher education
institutions at undergraduate level. It is usually taken by students who
are graduated from high schools. In this paper, we reflect the major
educational school graduates issues and propose ICT-based test
preparation environment, known as ‘Online Kankor Exam Prep
System’ to give students the tools to help them pass the university
entrance exam on the first try. The system is based on Intelligent
Tutoring System (ITS), which introduced an essential package of
educational technology for learners that features: (I) exam-focused
questions and content; (ii) self-assessment environment; and (iii) test
preparation strategies in order to help students to acquire the necessary
skills in their carrier and keep them up-to-date with instruction.
Abstract: This paper describes a novel application of Fiber
Braggs Grating (FBG) sensors in the assessment of human postural
stability and balance on an unstable platform. In this work, FBG
sensor Stability Analyzing Device (FBGSAD) is developed for
measurement of plantar strain to assess the postural stability of
subjects on unstable platforms during different stances in eyes open
and eyes closed conditions on a rocker board. The studies are
validated by comparing the Centre of Gravity (CG) variations
measured on the lumbar vertebra of subjects using a commercial
accelerometer. The results obtained from the developed FBGSAD
depict qualitative similarities with the data recorded by commercial
accelerometer. The advantage of the FBGSAD is that it measures
simultaneously plantar strain distribution and postural stability of the
subject along with its inherent benefits like non-requirement of
energizing voltage to the sensor, electromagnetic immunity and
simple design which suits its applicability in biomechanical
applications. The developed FBGSAD can serve as a tool/yardstick to
mitigate space motion sickness, identify individuals who are
susceptible to falls and to qualify subjects for balance and stability,
which are important factors in the selection of certain unique
professionals such as aircraft pilots, astronauts, cosmonauts etc.
Abstract: Nowadays, the successful implementation of ICTs is
vital for almost any kind of organization. Good governance and ICT
management are essential for delivering value, managing
technological risks, managing resources and performance
measurement. In addition, outsourcing is a strategic IT service
solution which complements IT services provided internally in
organizations. This paper proposes the measurement tools of a new
holistic maturity model based on standards ISO/IEC 20000 and
ISO/IEC 38500, and the frameworks and best practices of ITIL and
COBIT, with a specific focus on IT outsourcing. These measurement
tools allow independent validation and practical application in the
field of higher education, using a questionnaire, metrics tables, and
continuous improvement plan tables as part of the measurement
process. Guidelines and standards are proposed in the model for
facilitating adaptation to universities and achieving excellence in the
outsourcing of IT services.
Abstract: Background: Taiwan now is an aging society. Research
on the elderly should not be confined to caring for seniors, but should
also be focused on ways to improve health and the quality of life.
Senior citizens who participate in volunteer services could become
less lonely, have new growth opportunities, and regain a sense of
accomplishment. Thus, the question of how to get the elderly to
participate in volunteer service is worth exploring. Objective: Apply
the Transtheoretical Model to understand stages of change in regular
volunteer service and voluntary service behaviour among the seniors.
Methods: 1525 adults over the age of 65 from the Renai district of
Keelung City were interviewed. The research tool was a
self-constructed questionnaire, and individual interviews were
conducted to collect data. Then the data was processed and analyzed
using the IBM SPSS Statistics 20 (Windows version) statistical
software program. Results: In the past six months, research subjects
averaged 9.92 days of volunteer services. A majority of these elderly
individuals had no intention to change their regular volunteer services.
We discovered that during the maintenance stage, the self-efficacy for
volunteer services was higher than during all other stages, but
self-perceived barriers were less during the preparation stage and
action stage. Self-perceived benefits were found to have an important
predictive power for those with regular volunteer service behaviors in
the previous stage, and self-efficacy was found to have an important
predictive power for those with regular volunteer service behaviors in
later stages. Conclusions/Implications for Practice: The research
results support the conclusion that community nursing staff should
group elders based on their regular volunteer services change stages
and design appropriate behavioral change strategies.
Abstract: The objective of the present study is to determine
better eye end design of a mono leaf spring used in light motor
vehicle. A conventional 65Si7 spring steel leaf spring model with
standard eye, casted and riveted eye end are considered. The CAD
model of the leaf springs is prepared in CATIA and analyzed using
ANSYS. The standard eye, casted and riveted eye leaf springs are
subjected to similar loading conditions. The CAE analysis of the leaf
spring is performed for various parameters like deflection and Von-
Mises stress. Mass reduction of 62.9% is achieved in case of riveted
eye mono leaf spring as compared to standard eye mono leaf spring
for the same loading conditions.
Abstract: Taking the design tolerance into account, this paper
presents a novel efficient approach to generate iso-scallop tool path for
five-axis strip machining with a barrel cutter. The cutter location is
first determined on the scallop surface instead of the design surface,
and then the cutter is adjusted to locate the optimal tool position based
on the differential rotation of the tool axis and satisfies the design
tolerance simultaneously. The machining strip width and error are
calculated with the aid of the grazing curve of the cutter. Based on the
proposed tool positioning algorithm, the tool paths are generated by
keeping the scallop height formed by adjacent tool paths constant. An
example is conducted to confirm the validity of the proposed method.
Abstract: E-learning has become an efficient and widespread
means of education at all levels of human activities. Statistics is no
exception. Unfortunately the main focus in statistics teaching is
usually paid to the substitution in formulas. Suitable websites can
simplify and automate calculations and provide more attention and
time to the basic principles of statistics, mathematization of real-life
situations and following interpretation of results. We now introduce
our own web-site for hypothesis testing. Its didactic aspects, the
technical possibilities of the individual tools, the experience of use
and the advantages or disadvantages are discussed in this paper. This
web-site is not a substitute for common statistical software but should
significantly improve the teaching of statistics at universities.
Abstract: Real time image and video processing is a demand in
many computer vision applications, e.g. video surveillance, traffic
management and medical imaging. The processing of those video
applications requires high computational power. Thus, the optimal
solution is the collaboration of CPU and hardware accelerators. In
this paper, a Canny edge detection hardware accelerator is proposed.
Edge detection is one of the basic building blocks of video and image
processing applications. It is a common block in the pre-processing
phase of image and video processing pipeline. Our presented
approach targets offloading the Canny edge detection algorithm from
processing system (PS) to programmable logic (PL) taking the
advantage of High Level Synthesis (HLS) tool flow to accelerate the
implementation on Zynq platform. The resulting implementation
enables up to a 100x performance improvement through hardware
acceleration. The CPU utilization drops down and the frame rate
jumps to 60 fps of 1080p full HD input video stream.
Abstract: Cloud computing has provided the impetus for change
in the demand, sourcing, and consumption of IT-enabled services.
The technology developed from an emerging trend towards a ‘musthave’.
Many organizations harnessed on the quick-wins of cloud
computing within the last five years but nowadays reach a plateau
when it comes to sustainable savings and performance. This study
aims to investigate what is needed from an organizational perspective
to make cloud computing a sustainable success. The study was
carried out in Germany among senior IT professionals, both in
management and delivery positions. Our research shows that IT
executives must be prepared to realign their IT workforce to sustain
the advantage of cloud computing for today and the near future.
While new roles will undoubtedly emerge, roles alone cannot ensure
the success of cloud deployments. What is needed is a change in the
IT workforce’s business behaviour, or put more simply, the ways in
which the IT personnel works. It gives clear guidance on which
dimensions of an employees’ working behaviour need to be adapted.
The practical implications are drawn from a series of semi-structured
interviews, resulting in a high-level workforce enablement plan.
Lastly, it elaborates on tools and gives clear guidance on which
pitfalls might arise along the proposed workforce enablement
process.
Abstract: Software Architecture is the basic structure of
software that states the development and advancement of a software
system. Software architecture is also considered as a significant tool
for the construction of high quality software systems. A clean design
leads to the control, value and beauty of software resulting in its
longer life while a bad design is the cause of architectural erosion
where a software evolution completely fails. This paper discusses the
occurrence of software architecture erosion and presents a set of
methods for the detection, declaration and prevention of architecture
erosion. The causes and symptoms of architecture erosion are
observed with the examples of prescriptive and descriptive
architectures and the practices used to stop this erosion are also
discussed by considering different types of software erosion and their
affects. Consequently finding and devising the most suitable
approach for fighting software architecture erosion and in some way
reducing its affect is evaluated and tested on different scenarios.
Abstract: Braille alphabet is an important tool that enables
visually impaired individuals to have a comfortable life like those
who have normal vision. For this reason, new applications related to
the Braille alphabet are being developed. In this study, a new
Refreshable Braille Display was developed to help visually impaired
individuals learn the Braille alphabet easier. By means of this system,
any text downloaded on a computer can be read by the visually
impaired individual at that moment by feeling it by his/her hands.
Through this electronic device, it was aimed to make learning the
Braille alphabet easier for visually impaired individuals with whom
the necessary tests were conducted.
Abstract: Knowledge management is considered as an important
factor in improving health care services. KM facilitates the transfer of
existing knowledge and the development of new knowledge in
hospitals. This paper reviews practices adopted by doctors in Kuwait
for capturing, sharing, and generating knowledge. It also discusses
the perceived impact of KM practices on performance of hospitals.
Based on a survey of 277 doctors, the study found that KM practices
among doctors in the sampled hospitals were not very effective. Little
attention was paid to the main activities that support the transfer of
expertise among doctors in hospitals. However, as predicted by
previous studies, good km practices were perceived by doctors to
have a positive impact on performance of hospitals. It was concluded
that through effective KM practices hospitals could improve the
services they provide. Documentation of best practices and capturing
of lessons learnt for re-use of knowledge could help transform the
hospitals into learning organizations.