Abstract: Given a graph G. A cycle of G is a sequence of
vertices of G such that the first and the last vertices are the same.
A hamiltonian cycle of G is a cycle containing all vertices of G.
The graph G is k-ordered (resp. k-ordered hamiltonian) if for any
sequence of k distinct vertices of G, there exists a cycle (resp.
hamiltonian cycle) in G containing these k vertices in the specified
order. Obviously, any cycle in a graph is 1-ordered, 2-ordered and 3-
ordered. Thus the study of any graph being k-ordered (resp. k-ordered
hamiltonian) always starts with k = 4. Most studies about this topic
work on graphs with no real applications. To our knowledge, the
chordal ring families were the first one utilized as the underlying
topology in interconnection networks and shown to be 4-ordered.
Furthermore, based on our computer experimental results, it was
conjectured that some of them are 4-ordered hamiltonian. In this
paper, we intend to give some possible directions in proving the
conjecture.
Abstract: This paper presents the scaling laws that provide the
criteria of geometry and dynamic similitude between the full-size
rotor-shaft system and its scale model, and can be used to predict the
torsional vibration characteristics of the full-size rotor-shaft system by
manipulating the corresponding data of its scale model. The scaling
factors, which play fundamental roles in predicting the geometry and
dynamic relationships between the full-size rotor-shaft system and its
scale model, for torsional free vibration problems between scale and
full-size rotor-shaft systems are firstly obtained from the equation of
motion of torsional free vibration. Then, the scaling factor of external
force (i.e., torque) required for the torsional forced vibration problems
is determined based on the Newton’s second law. Numerical results
show that the torsional free and forced vibration characteristics of a
full-size rotor-shaft system can be accurately predicted from those of
its scale models by using the foregoing scaling factors. For this reason,
it is believed that the presented approach will be significant for
investigating the relevant phenomenon in the scale model tests.
Abstract: Future flood can be predicted using the probable
maximum flood (PMF). PMF is calculated using the historical
discharge or rainfall data considering the other climatic parameters
remaining stationary. However climate is changing globally and the
key climatic variables are temperature, evaporation, rainfall and sea
level rise are likely to change. To develop scenarios to a basin or
catchment scale these important climatic variables should be
considered. Nowadays scenario based on climatic variables is more
suitable than PMF. Six scenarios were developed for a large Fitzroy
basin and presented in this paper.
Abstract: Cloud computing (CC) has already gained overall
appreciation in research and practice. Whereas the willingness to
integrate cloud services in various IT environments is still unbroken,
the previous CC procurement processes run mostly in an unorganized
and non-standardized way. In practice, a sufficiently specific, yet
applicable business process for the important acquisition phase is
often lacking. And research does not appropriately remedy this
deficiency yet. Therefore, this paper introduces a field-tested
approach for CC procurement. Based on an extensive literature
review and augmented by expert interviews, we designed a model
that is validated and further refined through an in-depth real-life case
study. For the detailed process description, we apply the event-driven
process chain notation (EPC). The gained valuable insights into the
case study may help CC research to shift to a more socio-technical
area. For practice, next to giving useful organizational instructions
we will provide extended checklists and lessons learned.
Abstract: Replacement of plastics used in the food industry
seems to be a serious issue to overcome mainly the environmental
problems in recent years. This study investigates the hydrophilicity
and permeability properties of starch biopolymer which ethylene
vinyl alcohol (EVOH) (0-10%) and nanocrystalline cellulose (NCC)
(1-15%) were used to enhance its properties. Starch -EVOH
nanocomposites were prepared by casting method in different
formulations. NCC production by acid hydrolysis was confirmed by
scanning electron microscopy. Solubility, water vapor permeability,
water vapor transmission rate and moisture absorbance were
measured on each of the nanocomposites. The results were analyzed
by SAS software. The lowest moisture absorbance was measured in
pure starch nanocomposite containing 8% NCC. The lowest
permeability to water vapor belongs to starch nanocomposite
containing 8% NCC and the sample containing 7.8% EVOH and 13%
NCC. Also the lowest solubility was observed in the composite
contains the highest amount of EVOH. Applied Process resulted in
production of bio films which have good resistance to water vapor
permeability and solubility in water. The use of NCC and EVOH
leads to reduced moisture absorbance property of the biofilms.
Abstract: This paper proposed a silicon controller rectifier (SCR)
based ESD protection device to protect low voltage ESD for integrated
circuit. The proposed ESD protection device has low trigger voltage
and high holding voltage compared with conventional SCR-based
ESD protection devices. The proposed ESD protection circuit is
verified and compared by TCAD simulation. This paper verified
effective low voltage ESD characteristics with low trigger voltage of
5.79V and high holding voltage of 3.5V through optimization
depending on design variables (D1, D2, D3 and D4).
Abstract: Examining existing experimental results for shallow
rigid foundations subjected to vertical centric load (N), accompanied
or not with a bending moment (M), two main non-linear mechanisms
governing the cyclic response of the soil-foundation system can be
distinguished: foundation uplift and soil yielding. A soil-foundation
failure limit, is defined as a domain of resistance in the two
dimensional (2D) load space (N, M) inside of which lie all the
admissible combinations of loads; these latter correspond to a pure
elastic, non-linear elastic or plastic behavior of the soil-foundation
system, while the points lying on the failure limit correspond to a
combination of loads leading to a failure of the soil-foundation
system. In this study, the proposed resistance domain is constructed
analytically based on mechanics. Original elastic limit, uplift
initiation limit and iso-uplift limits are constructed inside this
domain. These limits give a prediction of the mechanisms activated
for each combination of loads applied to the foundation. A
comparison of the proposed failure limit with experimental tests
existing in the literature shows interesting results. Also, the
developed uplift initiation limit and iso-uplift curves are confronted
with others already proposed in the literature and widely used due to
the absence of other alternatives, and remarkable differences are
noted, showing evident errors in the past proposals and relevant
accuracy for those given in the present work.
Abstract: Locating Radio Controlled (RC) devices using their
unintended emissions has a great interest considering security
concerns. Weak nature of these emissions requires near field
localization approach since it is hard to detect these signals in far
field region of array. Instead of only angle estimation, near field
localization also requires range estimation of the source which makes
this method more complicated than far field models. Challenges of
locating such devices in a near field region and real time environment
are analyzed in this paper. An ESPRIT like near field localization
scheme is utilized for both angle and range estimation. 1-D search
with symmetric subarrays is provided. Two 7 element uniform linear
antenna arrays (ULA) are employed for locating RC source.
Experiment results of location estimation for one unintended emitting
walkie-talkie for different positions are given.
Abstract: In situ modified cyclohexanone-formaldehyde resins
were prepared by addition of alendronic acid during resin
preparation. Clay nanocomposites in ketonic resins were achieved by
adding clay into the flask at the beginning of the resin preparation.
The prepared resins were used for the synthesis of fire resistant
polyurethanes foam. Both phosphorous containing modifier
compound alendronic acid and nanoclay increases fire resistance of
the cyclohexanone-formaldehyde resin thus polyurethane produced
from these resins. The effect of the concentrations of alendronic acid
and clay on the fire resistance and physical properties of
polyurethanes was studied.
Abstract: Testing the first year students of Informatics at the
University of Debrecen revealed that students start their tertiary
studies in programming with a low level of programming knowledge
and algorithmic skills. The possible reasons which lead the students
to this very unfortunate result were examined. The results of the test
were compared to the students’ results in the school leaving exams
and to their self-assessment values. It was found that there is only a
slight connection between the students’ results in the test and in the
school leaving exams, especially at intermediate level. Beyond this,
the school leaving exams do not seem to enable students to evaluate
their own abilities.
Abstract: In the scope of application of technical textiles, Non-
Crimp Fabrics are increasingly used. In general, NCF exhibit
excellent load bearing properties, but caused by the manufacturing
process, there are some remaining disadvantages which have to be
reduced. Regarding to this, a novel technique of processing NCF was
developed substituting the binding-thread by an adhesive. This stitchfree
method requires new manufacturing concept as well as new basic
methods to prove adhesion of glue at fibres and textiles. To improve
adhesion properties and the wettability of carbon-fibres by the
adhesive, oxy-fluorination was used. The modification of carbonfibres
by oxy-fluorination was investigated via scanning electron
microscope, X-ray photoelectron spectroscopy and single fibre
tensiometry. Special tensile tests were developed to determine the
maximum force required for detachment.
Abstract: An exploration of the related literature reveals that all
instruction methods aim at training autonomous learners. After the
turn of second language pedagogy toward learner-oriented strategies,
learners’ needs were more focused. Yet; the historical, social and
political aspects of learning were still neglected. The present study
investigates the notion of autonomous learning and explains its
various facets from a pedagogical point of view. Furthermore;
different elements, fields and scopes of autonomous learning will be
explored. After exploring different aspects of autonomy, it is
postulated that liberatory autonomy is highlighted since it not only
covers social autonomy but also reveals learners’ capabilities and
human potentials. It is also recommended that learners consider
different elements of autonomy such as motivation, knowledge,
confidence, and skills.
Abstract: In-memory database systems are becoming popular
due to the availability and affordability of sufficiently large RAM and
processors in modern high-end servers with the capacity to manage
large in-memory database transactions. While fast and reliable inmemory
systems are still being developed to overcome cache misses,
CPU/IO bottlenecks and distributed transaction costs, disk-based data
stores still serve as the primary persistence. In addition, with the
recent growth in multi-tenancy cloud applications and associated
security concerns, many organisations consider the trade-offs and
continue to require fast and reliable transaction processing of diskbased
database systems as an available choice. For these
organizations, the only way of increasing throughput is by improving
the performance of disk-based concurrency control. This warrants a
hybrid database system with the ability to selectively apply an
enhanced disk-based data management within the context of inmemory
systems that would help improve overall throughput.
The general view is that in-memory systems substantially
outperform disk-based systems. We question this assumption and
examine how a modified variation of access invariance that we call
enhanced memory access, (EMA) can be used to allow very high
levels of concurrency in the pre-fetching of data in disk-based
systems. We demonstrate how this prefetching in disk-based systems
can yield close to in-memory performance, which paves the way for
improved hybrid database systems. This paper proposes a novel EMA
technique and presents a comparative study between disk-based EMA
systems and in-memory systems running on hardware configurations
of equivalent power in terms of the number of processors and their
speeds. The results of the experiments conducted clearly substantiate
that when used in conjunction with all concurrency control
mechanisms, EMA can increase the throughput of disk-based systems
to levels quite close to those achieved by in-memory system. The
promising results of this work show that enhanced disk-based
systems facilitate in improving hybrid data management within the
broader context of in-memory systems.
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: In this study, we propose a novel technique for acoustic
echo suppression (AES) during speech recognition under barge-in
conditions. Conventional AES methods based on spectral subtraction
apply fixed weights to the estimated echo path transfer function
(EPTF) at the current signal segment and to the EPTF estimated until
the previous time interval. However, the effects of echo path changes
should be considered for eliminating the undesired echoes. We
describe a new approach that adaptively updates weight parameters in
response to abrupt changes in the acoustic environment due to
background noises or double-talk. Furthermore, we devised a voice
activity detector and an initial time-delay estimator for barge-in speech
recognition in communication networks. The initial time delay is
estimated using log-spectral distance measure, as well as
cross-correlation coefficients. The experimental results show that the
developed techniques can be successfully applied in barge-in speech
recognition systems.
Abstract: An efficient and green method for oxidation of thiols
to the corresponding disulfides is reported using ionic liquid
[HSO3N(C2H4OSO3H)3] in the presence of free nano-Fe2O3 at 60°C.
Ionic liquid is selective oxidant for S-S Coupling variety aliphatic
and aromatic of thiols to corresponding disulfide in the presence of
free nano-Fe2O3 as recoverable catalyst. Reaction has been performed
in methanol as an inexpensive solvent. This reaction is clean and easy
work-up with no side reaction.
Abstract: Food as perishable goods represents a specific and
sensitive part in the supply chain theory, since changing physical or
chemical characteristics considerably influence the approach to stock
management. The most delicate phase of this process is
transportation, where it becomes difficult to ensure the stable
conditions which limit deterioration, since the value of the
deterioration rate could be easily influenced by the mode of
transportation. The fuzzy definition of variables allows one to take
these variations into account. Furthermore, an appropriate choice of
the defuzzification method permits one to adapt results to real
conditions as far as possible. In this article those methods which take
into account the relationship between the deterioration rate of
perishable goods and transportation by ship will be applied with the
aim of (a) minimizing the total cost function, defined as the sum of
the ordering cost, holding cost, disposing cost and transportation
costs, and (b) improving the supply chain sustainability by reducing
environmental impact and waste disposal costs.
Abstract: Electric vehicles are one of the most complicated
electric devices to simulate due to the significant number of different
processes involved in electrical structure of it. There are concurrent
processes of energy consumption and generation with different
onboard systems, which make simulation tasks more complicated to
perform. More accurate simulation on energy consumption can
provide a better understanding of all energy management for electric
transport. As a result of all those processes, electric transport can
allow for a more sustainable future and become more convenient in
relation to the distance range and recharging time. This paper
discusses the problems of energy consumption simulations for
electric vehicles using different software packages to provide ideas
on how to make this process more precise, which can help engineers
create better energy management strategies for electric vehicles.
Abstract: The purpose of this study is to examine the possible
link between employee and customer satisfaction. The service
provided by employees, help to build a good relationship with
customers and can help at increasing their loyalty. Published data for
job satisfaction and indicators of customer services of banks were
gathered from relevant published works which included data from
five different countries. The scores of customers and employees
satisfaction of the different published works were transformed and
normalized to the scale of 1 to 100. The data were analyzed and a
regression analysis of the two parameters was used to describe the
link between employee’s satisfaction and customer’s satisfaction.
Assuming that employee satisfaction has a significant influence on
customer’s service and the resulting customer satisfaction, the
reviewed data indicate that employee’s satisfaction contributes
significantly on the level of customer satisfaction in the Banking
sector. There was a significant correlation between the two
parameters (Pearson correlation R2=0.52 P
Abstract: Wet scrubbers have found widespread use in cleaning
contaminated gas streams because of their ability to remove
particulates and based on the applications of scrubbing of marine
engine exhaust gases by spraying sea-water. In order to examine the
flow characteristics inside the scrubber, the model is designated with
flow properties of hot air and water sprayer. The flow dynamics of
evaporation of hot air by the injection of water droplets is the key
factor considered in this paper. The flow behavior inside the scrubber
was investigated from the previous works and to sum up the
evaporation rate with respect to the concentration of water droplets are
predicted to bring out the competent modelling. The numerical
analysis using CFD facilitates in understanding the problem better and
empathies the behavior of the model over its entire operating envelope.