Abstract: When trying to enumerate all BIBD-s for given parameters,
their natural solution space appears to be huge and grows extremely with the number of points of the design. Therefore,
constructive enumerations are often carried out by assuming additional
constraints on design-s structure, automorphisms being mostly used ones. It remains a hard task to construct designs with trivial
automorphism group – those with no additional symmetry – although it is believed that most of the BIBD-s belong to that case. In
this paper, very many new designs with parameters 2-(13, 5, 5), 2-(16, 6, 5) and 2-(21, 6, 4) are constructed, assuming an action of an
automorphism of order 3. Even more, it was possible to construct millions of such designs with no non-trivial automorphisms.
Abstract: Benefits to the organisation are just as important as technical ability when it comes to software success. The challenge is to provide industry with professionals who understand this. In other words: How to teach computer engineering students to look beyond technology, and at the benefits of software to organizations? This paper reports on the conceptual design of a section of the computer networks module aimed to sensitize the students to the organisational context.
Checkland focuses on different worldviews represented by various role players in the organisation. He developed the Soft Systems Methodology that guides purposeful action in organisations, while incorporating different worldviews in the modeling process. If we can sensitize students to these methods, they are likely to appreciate the wider context of application of system software. This paper will provide literature on these concepts as well as detail on how the students will be guided to adopt these concepts.
Abstract: During last decades is widely discussed the
international harmonization of financial reporting. This
harmonization is also affected by national tax systems in analyzed
countries. This paper provides some evidence on current national tax
systems in selected countries in Central and Eastern Europe. The
linkage of accounting profit as a tax base might decrease the
administrative burden for majority of SMEs, which are the most
important engine of each national economy.
Abstract: In built-up structures, one of the effective ways of
dissipating unwanted vibration is to exploit the occurrence of slip at
the interfaces of structural laminates. The present work focuses on
the dynamic analysis of welded structures. A mathematical
formulation has been developed for the mechanism of slip damping
in layered and welded mild steel beams with unequal thickness
subjected to both periodic and non-periodic forces. It is observed that
a number of vital parameters such as; thickness ratio, pressure
distribution characteristics, relative slip and kinematic co-efficient of
friction at the interfaces, nature of exciting forces, length and
thickness of the beam specimen govern the damping characteristics of
these structures. Experimental verification has been carried out to
validate the analysis and study the effect of these parameters. The
developed damping model for the structure is found to be in fairly
good agreement with the measured data. Finally, the results of the
analysis are discussed and rationalized.
Abstract: Response surface methodology with Box–Benhken (BB) design of experiment approach has been utilized to study the mechanism of interface slip damping in layered and jointed tack welded beams with varying surface roughness. The design utilizes the initial amplitude of excitation, tack length and surface roughness at the interfaces to develop the model for the logarithmic damping decrement of the layered and jointed welded structures. Statistically designed experiments have been performed to estimate the coefficients in the mathematical model, predict the response, and check the adequacy of the model. Comparison of predicted and experimental response values outside the design conditions have shown good correspondence, implying that empirical model derived from response surface approach can be effectively used to describe the mechanism of interface slip damping in layered and jointed tack welded structures.
Abstract: The Institute of Product Development is dealing
with the development, design and dimensioning of micro components
and systems as a member of the Collaborative Research
Centre 499 “Design, Production and Quality Assurance of
Molded micro components made of Metallic and Ceramic Materials".
Because of technological restrictions in the miniaturization
of conventional manufacturing techniques, shape and
material deviations cannot be scaled down in the same proportion
as the micro parts, rendering components with relatively
wide tolerance fields. Systems that include such components
should be designed with this particularity in mind, often requiring
large clearance. On the end, the output of such systems
results variable and prone to dynamical instability. To save
production time and resources, every study of these effects
should happen early in the product development process and
base on computer simulation to avoid costly prototypes. A
suitable method is proposed here and exemplary applied to a
micro technology demonstrator developed by the CRC499. It
consists of a one stage planetary gear train in a sun-planet-ring
configuration, with input through the sun gear and output
through the carrier. The simulation procedure relies on ordinary
Multi Body Simulation methods and subsequently adds
other techniques to further investigate details of the system-s
behavior and to predict its response. The selection of the relevant
parameters and output functions followed the engineering
standards for regular sized gear trains. The first step is to
quantify the variability and to reveal the most critical points of
the system, performed through a whole-mechanism Sensitivity
Analysis. Due to the lack of previous knowledge about the system-s
behavior, different DOE methods involving small and
large amount of experiments were selected to perform the SA.
In this particular case the parameter space can be divided into
two well defined groups, one of them containing the gear-s profile
information and the other the components- spatial location.
This has been exploited to explore the different DOE techniques
more promptly. A reduced set of parameters is derived for
further investigation and to feed the final optimization process,
whether as optimization parameters or as external perturbation
collective. The 10 most relevant perturbation factors and 4 to 6
prospective variable parameters are considered in a new, simplified
model. All of the parameters are affected by the mentioned
production variability. The objective functions of interest
are based on scalar output-s variability measures, so the
problem becomes an optimization under robustness and reliability constrains. The study shows an initial step on the development
path of a method to design and optimize complex micro
mechanisms composed of wide tolerated elements accounting
for the robustness and reliability of the systems- output.
Abstract: The literature has argued that firms based in industrial districts enjoy advantages for creating internal knowledge and absorbing external knowledge as a consequence of to the knowledge flows and spillovers that exist in the district. However, empirical evidence to show how belonging to an industrial district affects the business processes of creation and absorption of knowledge is scarce and, moreover, empirical research has not taken into account the influence of variations in the flows of knowledge circulating in each cluster. This study aims to extend empirical evidence on the effect that the stock of shared competencies in industrial districts has on the business processes of creation and absorption of knowledge, through data from an initial study on 952 firms and 35 industrial districts in Spain.
Abstract: In a handwriting recognition problem, characters can
be represented using chain codes. The main problem in representing
characters using chain code is optimizing the length of the chain
code. This paper proposes to use randomized algorithm to minimize
the length of Freeman Chain Codes (FCC) generated from isolated
handwritten characters. Feedforward neural network is used in the
classification stage to recognize the image characters. Our test results
show that by applying the proposed model, we reached a relatively
high accuracy for the problem of isolated handwritten when tested on
NIST database.
Abstract: The aim of this work was to detect genetic variability among the set of 40 castor genotypes using 8 RAPD markers. Amplification of genomic DNA of 40 genotypes, using RAPD analysis, yielded in 66 fragments, with an average of 8.25 polymorphic fragments per primer. Number of amplified fragments ranged from 3 to 13, with the size of amplicons ranging from 100 to 1200 bp. Values of the polymorphic information content (PIC) value ranged from 0.556 to 0.895 with an average of 0.784 and diversity index (DI) value ranged from 0.621 to 0.896 with an average of 0.798. The dendrogram based on hierarchical cluster analysis using UPGMA algorithm was prepared and analyzed genotypes were grouped into two main clusters and only two genotypes could not be distinguished. Knowledge on the genetic diversity of castor can be used for future breeding programs for increased oil production for industrial uses.
Abstract: The notion of intuitionistic fuzzy sets was introduced
by Atanassov as a generalization of the notion of fuzzy sets. Y.B. Jun
and S.Z. Song introduced the notion of intuitionistic fuzzy points.
In this paper we find some relations between the intuitionistic fuzzy
ideals of a semigroup S and the set of all intuitionistic fuzzy points
of S.
Abstract: To increase precision and reliability of automatic control systems, we have to take into account of random factors affecting the control system. Thus, operational matrix technique is used for statistical analysis of first order plus time delay system with uniform random parameter. Examples with deterministic and stochastic disturbance are considered to demonstrate the validity of the method. Comparison with Monte Carlo method is made to show the computational effectiveness of the method.
Abstract: Humic acids (HAs) have been shown to activate some
ion uptakes along with stimulating the lateral roots at effective
concentration of micronutrients. However, the effects of HA on ion
adsorption by plant roots are not easily explainable due to the
varieties of HAs that differ from origins. Therefore, this study was
aimed to investigate the effect of various concentrations of HA
obtained from the compost derived from mix manures and some
agricultural wastes on the growth of eggplant seedlings (Solanum
melongena L. cv. Chao Praya) in tissue cultures at low nutrient level.
Egg plant seeds were surfaced sterilized and germinated in ½
Murashige and Skoog medium (MS) without HA added or in ¼ MS
supplemented with 0, 25, 50, 75 and 100 ppm of HAs. Then, they
were cultured for 4 weeks under the controlled environment. The
results showed that seedlings grown on ¼MS supplemented with
HAs at the concentration of 25 and 50 ppm had the average plant
heights (2.49 and 2.28 cm, respectively) higher than the other
treatments. Both treatments also significantly showed the maximum
average fresh and dry weights (p
Abstract: The purpose of this study is to investigate the chemical
degradation of the organophosphorus pesticide of parathion and
carbamate insecticide of methomyl in the aqueous phase through
Fenton process. With the employment of batch Fenton process, the
degradation of the two selected pesticides at different pH, initial
concentration, humic acid concentration, and Fenton reagent dosages
was explored. The Fenton process was found effective to degrade
parathion and methomyl. The optimal dosage of Fenton reagents (i.e.,
molar concentration ratio of H2O2 to Fe2+) at pH 7 for parathion
degradation was equal to 3, which resulted in 50% removal of
parathion. Similarly, the optimal dosage for methomyl degradation
was 1, resulting in 80% removal of methomyl. This study also found
that the presence of humic substances has enhanced pesticide
degradation by Fenton process significantly. The mass spectroscopy
results showed that the hydroxyl free radical may attack the single
bonds with least energy of investigated pesticides to form smaller
molecules which is more easily to degrade either through
physio-chemical or bilolgical processes.
Abstract: The nonlinear chaotic non-autonomous fourth order
system is algebraically simple but can generate complex chaotic
attractors. In this paper, non-autonomous fourth order chaotic
oscillator circuits were designed and simulated. Also chaotic nonautonomous
Attractor is addressed suitable for chaotic masking
communication circuits using Matlab® and MultiSIM® programs.
We have demonstrated in simulations that chaos can be synchronized
and applied to signal masking communications. We suggest that this
phenomenon of chaos synchronism may serve as the basis for little
known chaotic non-autonomous Attractor to achieve signal masking
communication applications. Simulation results are used to visualize
and illustrate the effectiveness of non-autonomous chaotic system in
signal masking. All simulations results performed on nonautonomous
chaotic system are verify the applicable of secure
communication.
Abstract: Rainbow trout homogametic males, (XX or YY sex genotype), can be obtained, respectively, through masculinisation of genetic females or induced androgenesis. Aim of this study was to compare reproductive potential of neo-males (XX) and super-males (YY) with heterogametic males (XY). We measured spermatozoa motility parameters, sperm concentration, osmolality and characterized protein profiles in samples of stripped and testicular sperm obtained from XY and YY males, and testicular sperm of XX males. The motile spermatozoa, as measured by both subjective method and CASA, showed no differences between testicular sperm of XX males and stripped sperm of XY and YY males whereas testicular sperm of XY and YY males had significantly lower sperm motility. Result of protein densitometry showed similarities in protein profile between seminal plasma of XY and YY males and testicular fluids of XX males. Testis of XX males showed specific histological structures of cysts consists hypertrophied Sertoli cells.
Abstract: A mobile ad hoc network is a network of mobile nodes
without any notion of centralized administration. In such a network,
each mobile node behaves not only as a host which runs applications
but also as a router to forward packets on behalf of others. Clustering
has been applied to routing protocols to achieve efficient
communications. A CH network expresses the connected relationship
among cluster-heads. This paper discusses the methods for
constructing a CH network, and produces the following results: (1)
The required running costs of 3 traditional methods for constructing a
CH network are not so different from each other in the static
circumstance, or in the dynamic circumstance. Their running costs in
the static circumstance do not differ from their costs in the dynamic
circumstance. Meanwhile, although the routing costs required for the
above 3 methods are not so different in the static circumstance, the
costs are considerably different from each other in the dynamic
circumstance. Their routing costs in the static circumstance are also
very different from their costs in the dynamic circumstance, and the
former is one tenths of the latter. The routing cost in the dynamic
circumstance is mostly the cost for re-routing. (2) On the strength of
the above results, we discuss new 2 methods regarding whether they
are tolerable or not in the dynamic circumstance, that is, whether the
times of re-routing are small or not. These new methods are revised
methods that are based on the traditional methods. We recommended
the method which produces the smallest routing cost in the dynamic
circumstance, therefore producing the smallest total cost.
Abstract: Background: Regular physical activity contributes
positively to physical and psychological health. In the present study,
the stages of change of physical activity and the total physical
Aims: The aim of this study was to investigate the proportion of
adolescent girls in each stages of change and the causative factors
associated with physical activity such as the related social support
and self efficacy in a sample of the high school students.
Methods: In this study, Social Cognitive Theory (SCT) and the
Transtheorical Model (TTM) guided instrument development. The
data regarding the demographics, psychosocial determinants of
physical activity, stage of change and physical activity was gathered
by questionnaires. Several measures of psychosocial determinants of
physical activity were translated from English into Persian using the
back-translation technique. These translated measures were
administered to 512 ninth and tenth-grade Iranian high school
students for factor analysis.
Results: The distribution of the stage of change for physical activity
was as follow: 18/5% in precontemplation, 23.4% in contemplation,
38.2% in preparation, 4.6% in action and 15.3% in maintenance.
They were in 80.1% pre-adoption stages (precontemplation stage,
contemplation stage and preparation stage) and 19.9% post-adoption
stages (action stage and maintenance stage) of physical activity.
There was a significant relate between age and physical activity in
adolescent girls (age-related decline of physical activity) p
Abstract: This paper presents a digital engineering library – the
Digital Mechanism and Gear Library, DMG-Lib – providing a multimedia collection of e-books, pictures, videos and animations in the domain of mechanisms and machines. The specific characteristic
about DMG-Lib is the enrichment and cross-linking of the different
sources. DMG-Lib e-books not only present pages as pixel images
but also selected figures augmented with interactive animations. The
presentation of animations in e-books increases the clearness of the
information.
To present the multimedia e-books and make them available in the
DMG-Lib internet portal a special e-book reader called StreamBook
was developed for optimal presentation of digitized books and to
enable reading the e-books as well as working efficiently and individually with the enriched information. The objective is to support different user tasks ranging from information retrieval to
development and design of mechanisms.
Abstract: We introduce a logic-based framework for database
updating under constraints. In our framework, the constraints are
represented as an instantiated extended logic program. When performing
an update, database consistency may be violated. We provide
an approach of maintaining database consistency, and study the
conditions under which the maintenance process is deterministic. We
show that the complexity of the computations and decision problems
presented in our framework is in each case polynomial time.
Abstract: Phytotoxicity of Daphne gnidium L. was evaluated
through the effect of incorporating leaves, stems and roots biomass
into soil (at 12.5, 25, 50g/Kg) and irrigation by their aqueous extracts
(50g/L), on the growth of two crops (Lactuca sativa L. and Raphanus
sativus L.) and two weeds (Peaganum harmala L. and Scolymus
maculatus L.). Results revealed a perceptible phytotoxic effect which
increased with dose and concentration. At the highest dose, roots and
leaves residues was the most toxic and caused total inhibition
respectively, for lettuce and thistle seedling growth. Irrigation with
aqueous extracts of D. gnidium different organs decreased also
seedlings length of all test species. Stems extract was more inhibitor
on thistle than peganum seedling growth; it induced a significant
reduction of 80% and 67%, for, respectively, roots and shoots.
Results of the present study suggest that different organs of D.
gnidium could be exploited in the management of agro-ecosystems.