Abstract: Since 1984 many schemes have been proposed for
digital signature protocol, among them those that based on discrete
log and factorizations. However a new identification scheme based
on iterated function (IFS) systems are proposed and proved to be
more efficient. In this study the proposed identification scheme is
transformed into a digital signature scheme by using a one way hash
function. It is a generalization of the GQ signature schemes. The
attractor of the IFS is used to obtain public key from a private one,
and in the encryption and decryption of a hash function. Our aim is
to provide techniques and tools which may be useful towards
developing cryptographic protocols. Comparisons between the
proposed scheme and fractal digital signature scheme based on RSA
setting, as well as, with the conventional Guillou-Quisquater
signature, and RSA signature schemes is performed to prove that, the
proposed scheme is efficient and with high performance.
Abstract: The spatial variation in plant species associated with intercropping is intended to reduce resource competition between species and increase yield potential. A field experiment was carried out on corn (Zea mays L.) and soybean (Glycine max L.) intercropping in a replacement series experiment with weed contamination consist of: weed free, infestation of redroot pigweed, infestation of jimsonweed and simultaneous infestation of redroot pigweed and jimsonweed in Karaj, Iran during 2007 growing season. The experimental design was a randomized complete block in factorial experiment with replicated thrice. Significant (P≤0.05) differences were observed in yield in intercropping. Corn yield was higher in intercropping, but soybean yield was significantly reduced by corn when intercropped. However, total productivity and land use efficiency were high under the intercropping system even in contamination of either species of weeds. Aggressivity of corn relative to soybean revealed the greater competitive ability of corn than soybean. Land equivalent ratio (LER) more than 1 in all treatments attributed to intercropping advantages and was highest in 50: 50 (corn/soybean) in weed free. These findings suggest that intercropping corn and soybean increase total productivity per unit area and improve land use efficiency. Considering the experimental findings, corn-soybean intercropping (50:50) may be recommended for yield advantage, more efficient utilization of resources, and weed suppression as a biological control.
Abstract: In this paper we propose a computational model for the representation and processing of morpho-phonological phenomena in a natural language, like Modern Greek. We aim at a unified treatment of inflection, compounding, and word-internal phonological changes, in a model that is used for both analysis and generation. After discussing certain difficulties cuase by well-known finitestate approaches, such as Koskenniemi-s two-level model [7] when applied to a computational treatment of compounding, we argue that a morphology-based model provides a more adequate account of word-internal phenomena. Contrary to the finite state approaches that cannot handle hierarchical word constituency in a satisfactory way, we propose a unification-based word grammar, as the nucleus of our strategy, which takes into consideration word representations that are based on affixation and [stem stem] or [stem word] compounds. In our formalism, feature-passing operations are formulated with the use of the unification device, and phonological rules modeling the correspondence between lexical and surface forms apply at morpheme boundaries. In the paper, examples from Modern Greek illustrate our approach. Morpheme structures, stress, and morphologically conditioned phoneme changes are analyzed and generated in a principled way.
Abstract: In this paper, we discuss the paradigm shift in bank
capital from the “gone concern" to the “going concern" mindset. We
then propose a methodology for pricing a product of this shift called
Contingent Capital Notes (“CoCos"). The Merton Model can
determine a price for credit risk by using the firm-s equity value as a
call option on those assets. Our pricing methodology for CoCos also
uses the credit spread implied by the Merton Model in a subsequent
derivative form created by John Hull et al . Here, a market implied
asset volatility is calculated by using observed market CDS spreads.
This implied asset volatility is then used to estimate the probability of
triggering a predetermined “contingency event" given the distanceto-
trigger (DTT). The paper then investigates the effect of varying
DTTs and recovery assumptions on the CoCo yield. We conclude
with an investment rationale.
Abstract: To investigate the correspondence of theory and
practice, a successfully implemented Knowledge Management
System (KMS) is explored through the lens of Alavi and Leidner-s
proposed KMS framework for the analysis of an information system
in knowledge management (Framework-AISKM). The applied KMS
system was designed to manage curricular knowledge in a distributed
university environment. The motivation for the KMS is discussed
along with the types of knowledge necessary in an academic setting.
Elements of the KMS involved in all phases of capturing and
disseminating knowledge are described. As the KMS matures the
resulting data stores form the precursor to and the potential for
knowledge mining. The findings from this exploratory study indicate
substantial correspondence between the successful KMS and the
theory-based framework providing provisional confirmation for the
framework while suggesting factors that contributed to the system-s
success. Avenues for future work are described.
Abstract: In Knowledge Structure Graph, each course unit
represents a phase of learning activities. Both learning portfolios and
Knowledge Structure Graphs contain learning information of students
and let teachers know which content are difficulties and fails. The
study purposes "Dual Mode On-line Learning Diagnosis System" that
integrates two search methods: learning portfolio and knowledge
structure. Teachers can operate the proposed system and obtain the
information of specific students without any computer science
background. The teachers can find out failed students in advance and
provide remedial learning resources.
Abstract: Reservoirs with high pressures and temperatures
(HPHT) that were considered to be atypical in the past are now
frequent targets for exploration. For downhole oilfield drilling tools
and components, the temperature and pressure affect the mechanical
strength. To address this issue, a finite element analysis (FEA) for
206.84 MPa (30 ksi) pressure and 165°C has been performed on the
pressure housing of the measurement-while-drilling/logging-whiledrilling
(MWD/LWD) density tool.
The density tool is a MWD/LWD sensor that measures the density
of the formation. One of the components of the density tool is the
pressure housing that is positioned in the tool. The FEA results are
compared with the experimental test performed on the pressure
housing of the density tool. Past results show a close match between
the numerical results and the experimental test. This FEA model can
be used for extreme HPHT and ultra HPHT analyses, and/or optimal
design changes.
Abstract: Nowadays, Gene Ontology has been used widely by many researchers for biological data mining and information retrieval, integration of biological databases, finding genes, and incorporating knowledge in the Gene Ontology for gene clustering. However, the increase in size of the Gene Ontology has caused problems in maintaining and processing them. One way to obtain their accessibility is by clustering them into fragmented groups. Clustering the Gene Ontology is a difficult combinatorial problem and can be modeled as a graph partitioning problem. Additionally, deciding the number k of clusters to use is not easily perceived and is a hard algorithmic problem. Therefore, an approach for solving the automatic clustering of the Gene Ontology is proposed by incorporating cohesion-and-coupling metric into a hybrid algorithm consisting of a genetic algorithm and a split-and-merge algorithm. Experimental results and an example of modularized Gene Ontology in RDF/XML format are given to illustrate the effectiveness of the algorithm.
Abstract: General requirements for knowledge representation in
the form of logic rules, applicable to design and control of industrial
processes, are formulated. Characteristic behavior of decision trees
(DTs) and rough sets theory (RST) in rules extraction from recorded
data is discussed and illustrated with simple examples. The
significance of the models- drawbacks was evaluated, using
simulated and industrial data sets. It is concluded that performance of
DTs may be considerably poorer in several important aspects,
compared to RST, particularly when not only a characterization of a
problem is required, but also detailed and precise rules are needed,
according to actual, specific problems to be solved.
Abstract: In its attempt to offer new ways into autonomy for a
large population of disabled people, assistive technology has largely
been inspired by robotics engineering. Recent human-like robots
carry new hopes that it seems to us necessary to analyze by means of
a specific theory of anthropomorphism. We propose to distinguish a
functional anthropomorphism which is the one of actual wheelchairs
from a structural anthropomorphism based on a mimicking of human
physiological systems. If functional anthropomorphism offers the
main advantage of eliminating the physiological systems
interdependence issue, the highly link between the robot for disabled
people and their human-built environment would lead to privilege in
the future the anthropomorphic structural way. In this future
framework, we highlight a general interdependence principle : any
partial or local structural anthropomorphism generates new
anthropomorphic needs due to the physiological systems
interdependency, whose effects can be evaluated by means of
specific anthropomorphic criterions derived from a set theory-based
approach of physiological systems.
Abstract: Chlorine is one of the most abundant elements in
nature, which undergoes a complex biogeochemical cycle. Chlorine
bound in some substances is partly responsible for atmospheric ozone
depletion and contamination of some ecosystems. As due to
international regulations anthropogenic burden of volatile
organochlorines (VOCls) in atmosphere decreases, natural sources
(plants, soil, abiotic formation) are expected to dominate VOCl
production in the near future. Examples of plant VOCl production are
methyl chloride, and bromide emission from (sub)tropical ferns,
chloroform, 1,1,1-trichloroethane and tetrachloromethane emission
from temperate forest fern and moss. Temperate forests are found to
emit in addition to the previous compounds tetrachloroethene, and
brominated volatile compounds. VOCls can be taken up and further
metabolized in plants. The aim of this work is to identify and
quantitatively analyze the formed VOCls in temperate forest
ecosystems by a cryofocusing/GC-ECD detection method, hence
filling a gap of knowledge in the biogeochemical cycle of chlorine.
Abstract: Due to today-s fierce competition, companies have to
be proactive creators of the future by effectively developing
innovations. Especially radical innovations allow high profit margins
– but they also entail high risks. One possibility to realize radical
innovations and reduce the risk of failure is cross-industry innovation
(CII). CII brings together problems and solution ideas from different
industries. However, there is a lack of systematic ways towards CII.
Bridging this gap, the present paper provides a systematic approach
towards planned CII. Starting with the analysis of potentials, the
definition of promising search strategies is crucial. Subsequently,
identified solution ideas need to be assessed. For the most promising
ones, the adaption process has to be systematically planned –
regarding the risk affinity of a company. The introduced method is
explained on a project from the furniture industry.
Abstract: Small cracks or chips of a product appear very
frequently in the course of continuous production of an automatic
press process system. These phenomena become the cause of not only
defective product but also damage of a press mold. In order to solve
this problem AE system was introduced. AE system was expected to
be very effective to real time detection of the defective product and to
prevention of the damage of the press molds.
In this study, for pick and analysis of AE signals generated from the
press process, AE sensors/pre-amplifier/analysis and processing board
were used as frequently found in the other similar cases. For analysis
and processing the AE signals picked in real time from the good or bad
products, specialized software called cdm8 was used. As a result of
this work it was conformed that intensity and shape of the various AE
signals differ depending on the weight and thickness of metal sheet
and process type.
Abstract: Much research into handwritten Thai character
recognition have been proposed, such as comparing heads of
characters, Fuzzy logic and structure trees, etc. This paper presents a
system of handwritten Thai character recognition, which is based on
the Ant-minor algorithm (data mining based on Ant colony
optimization). Zoning is initially used to determine each character.
Then three distinct features (also called attributes) of each character
in each zone are extracted. The attributes are Head zone, End point,
and Feature code. All attributes are used for construct the
classification rules by an Ant-miner algorithm in order to classify
112 Thai characters. For this experiment, the Ant-miner algorithm is
adapted, with a small change to increase the recognition rate. The
result of this experiment is a 97% recognition rate of the training set
(11200 characters) and 82.7% recognition rate of unseen data test
(22400 characters).
Abstract: In this paper, the details of an experimental method to measure the clamping force value at bolted connections due to application of wrenching torque to tighten the nut have been presented. A simplified bolted joint including a holed plate with a single bolt was considered to carry out the experiments. This method was designed based on Hooke-s law by measuring compressive axial strain of a steel bush placed between the nut and the plate. In the experimental procedure, the values of clamping force were calculated for seven different levels of applied torque, and this process was repeated three times for each level of the torque. Moreover, the effect of lubrication of threads on the clamping value was studied using the same method. In both conditions (dry and lubricated threads), relation between the torque and the clamping force have been displayed in graphs.
Abstract: In networks, mainly small and medium-sized businesses benefit from the knowledge, experiences and solutions offered by experts from industry and science or from the exchange with practitioners. Associations which focus, among other things, on networking, information and knowledge transfer and which are interested in supporting such cooperations are especially well suited to provide such networks and the appropriate web platforms. Using METORA as an example – a project developed and run by the Federal Association for Information Economy, Telecommunications and New Media e.V. (BITKOM) for the Federal Ministry of Economics and Technology (BMWi) – This paper will discuss how associations and other network organizations can achieve this task and what conditions they have to consider.
Abstract: A novel PDE solver using the multidimensional wave
digital filtering (MDWDF) technique to achieve the solution of a 2D
seismic wave system is presented. In essence, the continuous physical
system served by a linear Kirchhoff circuit is transformed to an
equivalent discrete dynamic system implemented by a MD wave
digital filtering (MDWDF) circuit. This amounts to numerically
approximating the differential equations used to describe elements of a
MD passive electronic circuit by a grid-based difference equations
implemented by the so-called state quantities within the passive
MDWDF circuit. So the digital model can track the wave field on a
dense 3D grid of points. Details about how to transform the continuous
system into a desired discrete passive system are addressed. In
addition, initial and boundary conditions are properly embedded into
the MDWDF circuit in terms of state quantities. Graphic results have
clearly demonstrated some physical effects of seismic wave (P-wave
and S–wave) propagation including radiation, reflection, and
refraction from and across the hard boundaries. Comparison between
the MDWDF technique and the finite difference time domain (FDTD)
approach is also made in terms of the computational efficiency.
Abstract: The new framework the Higher Education is
immersed in involves a complete change in the way lecturers must
teach and students must learn. Whereas the lecturer was the main
character in traditional education, the essential goal now is to
increase the students' participation in the process. Thus, one of the
main tasks of lecturers in this new context is to design activities of
different nature in order to encourage such participation. Seminars
are one of the activities included in this environment. They are active
sessions that enable going in depth into specific topics as support of
other activities. They are characterized by some features such as
favoring interaction between students and lecturers or improving
their communication skills. Hence, planning and organizing strategic
seminars is indeed a great challenge for lecturers with the aim of
acquiring knowledge and abilities. This paper proposes a method
using Artificial Intelligence techniques to obtain student profiles
from their marks and preferences. The goal of building such profiles
is twofold. First, it facilitates the task of splitting the students into
different groups, each group with similar preferences and learning
difficulties. Second, it makes it easy to select adequate topics to be a
candidate for the seminars. The results obtained can be either a
guarantee of what the lecturers could observe during the development
of the course or a clue to reconsider new methodological strategies in
certain topics.
Abstract: The objective of this paper was to designing a
ventilation system to enhance the performance of roof solar collector
(RSC) for reducing heat accumulation inside the house. The RSC has
1.8 m2 surface area made of CPAC monier roof tiles on the upper part
and gypsum board on the lower part. The space between CPAC
monier and gypsum board was fixed at 14 cm.
Ventilation system of modified roof solar collector (modified
RSC) consists of 9 tubes of 0.15m diameter and installed in the
lower part of RSC. Experimental result showed that the temperature
of the room, and attic temperature. The average temperature
reduction of room of house used modified RSC is about 2oC. and the
percentage of room temperature reduction varied between 0 to 10%.
Therefore, modified RSC is an interesting option in the sense that it
promotes solar energy and conserve energy.
Abstract: Every day human life experiences new equipments
more automatic and with more abilities. So the need for faster
processors doesn-t seem to finish. Despite new architectures and
higher frequencies, a single processor is not adequate for many
applications. Parallel processing and networks are previous solutions
for this problem. The new solution to put a network of resources on a
chip is called NOC (network on a chip). The more usual topology for
NOC is mesh topology. There are several routing algorithms suitable
for this topology such as XY, fully adaptive, etc. In this paper we
have suggested a new algorithm named Intermittent X, Y (IX/Y). We
have developed the new algorithm in simulation environment to
compare delay and power consumption with elders' algorithms.