Abstract: The Canadian aerospace industry faces many
challenges. One of them is the difficulty in estimating costs. In
particular, the design effort required in a project impacts resource
requirements and lead-time, and consequently the final cost. This
paper presents the findings of a case study conducted for recognized
global leader in the design and manufacturing of aircraft engines. The
study models parametric cost estimation relationships to estimate the
design effort of integrated blade-rotor low-pressure compressor fans.
Several effort drivers are selected to model the relationship.
Comparative analyses of three types of models are conducted. The
model with the best accuracy and significance in design estimation is
retained.
Abstract: This paper presents three new methodologies for the
basic operations, which aim at finding new ways of computing union
(maximum) and intersection (minimum) membership values by
taking into effect the entire membership values in a fuzzy set. The
new methodologies are conceptually simple and easy from the
application point of view and are illustrated with a variety of
problems such as Cartesian product of two fuzzy sets, max –min
composition of two fuzzy sets in different product spaces and an
application of an inverted pendulum to determine the impact of the
new methodologies. The results clearly indicate a difference based on
the nature of the fuzzy sets under consideration and hence will be
highly useful in quite a few applications where different values have
significant impact on the behavior of the system.
Abstract: Autofluorescence (AF) bronchoscopy is an
established method to detect dysplasia and carcinoma in situ (CIS).
For this reason the “Sotiria" Hospital uses the Karl Storz D-light
system. However, in early tumor stages the visualization is not that
obvious. With the help of a PC, we analyzed the color images we
captured by developing certain tools in Matlab®. We used statistical
methods based on texture analysis, signal processing methods based
on Gabor models and conversion algorithms between devicedependent
color spaces. Our belief is that we reduced the error made
by the naked eye. The tools we implemented improve the quality of
patients' life.
Abstract: This paper presents design and implements the
T-DOF PI controller design for a speed control of induction motor.
The voltage source inverter type space vector pulse width modulation
technique is used the drive system. This scheme leads to be able to
adjust the speed of the motor by control the frequency and amplitude
of the input voltage. The ratio of input stator voltage to frequency
should be kept constant. The T-DOF PI controller design by root
locus technique is also introduced to the system for regulates and
tracking speed response. The experimental results in testing the 120
watt induction motor from no-load condition to rated condition show
the effectiveness of the proposed control scheme.
Abstract: In this paper we study some numerical methods to solve a model one-dimensional convection–diffusion equation. The semi-discretisation of the space variable results into a system of ordinary differential equations and the solution of the latter involves the evaluation of a matrix exponent. Since the calculation of this term is computationally expensive, we study some methods based on Krylov subspace and on Restrictive Taylor series approximation respectively. We also consider the Chebyshev Pseudospectral collocation method to do the spatial discretisation and we present the numerical solution obtained by these methods.
Abstract: Eigenvector methods are gaining increasing acceptance in the area of spectrum estimation. This paper presents a successful attempt at testing and evaluating the performance of two of the most popular types of subspace techniques in determining the parameters of multiexponential signals with real decay constants buried in noise. In particular, MUSIC (Multiple Signal Classification) and minimum-norm techniques are examined. It is shown that these methods perform almost equally well on multiexponential signals with MUSIC displaying better defined peaks.
Abstract: Lately there has been a significant boost of interest in
music digital libraries, which constitute an attractive area of research
and development due to their inherent interesting issues and
challenging technical problems, solutions to which will be highly
appreciated by enthusiastic end-users. We present here a DL that we
have developed to support users in their quest for classical music
pieces within a particular collection of 18,000+ audio recordings.
To cope with the early DL model limitations, we have used a refined
socio-semantic and contextual model that allows rich bibliographic
content description, along with semantic annotations, reviewing,
rating, knowledge sharing etc. The multi-layered service model
allows incorporation of local and distributed information,
construction of rich hypermedia documents, expressing the complex
relationships between various objects and multi-dimensional spaces,
agents, actors, services, communities, scenarios etc., and facilitates
collaborative activities to offer to individual users the needed
collections and services.
Abstract: Historic preservation areas are extremely vulnerable to disasters because they are home to many vulnerable people and contain many closely spaced wooden houses. However, the narrow streets in these regions have historic meaning, which means that they cannot be widened and can become blocked easily during large disasters. Here, we describe our efforts to establish a methodology for the planning of evacuation route sin such historic preservation areas. In particular, this study aims to clarify the effectiveness of measures intended to secure two-way evacuation routes for vulnerable people during large disasters in a historic area preserved under the Cultural Properties Protection Law, Japan.
Abstract: There are different kinds of online systems on the Internet for people who need support and develop new knowledge. Online communities and Ask the Expert systems are two such systems. In the health care area, the number of users of these systems has increased at a rapid pace. Interactions with medical trained experts take place online, and people with concerns about similar health problems come together to share experiences and advice. The systems are also used as storages and browsed for health information. Over the years, studies have been conducted of the usage of the different systems. However, in what ways the systems can be used together to enhance learning has not been explored. This paper presents results from a study of online health-communities and an Ask the Expert system for people who suffer from overweight. Differences and similarities in regards to posted issues and replies are discussed, and suggestions for a new holistic design of the two systems are presented.
Abstract: Swarm principles are increasingly being used to design controllers for the coordination of multi-robot systems or, in general, multi-agent systems. This paper proposes a two-dimensional Lagrangian swarm model that enables the planar agents, modeled as point masses, to swarm whilst effectively avoiding each other and obstacles in the environment. A novel method, based on an extended Lyapunov approach, is used to construct the model. Importantly, the Lyapunov method ensures a form of practical stability that guarantees an emergent behavior, namely, a cohesive and wellspaced swarm with a constant arrangement of individuals about the swarm centroid. Computer simulations illustrate this basic feature of collective behavior. As an application, we show how multiple planar mobile unicycle-like robots swarm to eventually form patterns in which their velocities and orientations stabilize.
Abstract: The role of neighborhood center as semi public (the
balance space) is disappeared in bonding between private and public
in new urbanism. In this way, a hierarchical principle in the
traditional neighborhood center appears to create or develop the
conditions for residents` relationships and belonging. This paper
evaluates significant of hierarchical principles of the neighborhood
center in residents` territoriality and its factors. In this way Miandeh
neighborhood center from Boshrooyeh city was determined as a case
study area. Results indicated that a hierarchical principle is the best
instrument to improve the territoriality as the subcomponent of place
belonging in residents. The findings help the urban designer to
revitalization the neighborhoods and proceedings in organization of
physical space.
Abstract: The design of an active leg orthosis for tumble
protection is proposed in this paper. The orthosis would be applied to
assist elders or invalids in rebalancing while they fall unexpectedly.
We observe the regain balance motion of healthy and youthful people,
and find the difference to elders or invalids. First, the physical model
of leg would be established, and we consider the leg motions are
achieve through four joints (phalanx stem, ankle, knee, and hip joint)
and five links (phalanges, talus, tibia, femur, and hip bone). To
formulate the dynamic equations, the coordinates which can clearly
describe the position in 3D space are first defined accordance with the
human movement of leg, and the kinematics and dynamics of the leg
movement can be formulated based on the robotics. For the purpose,
assisting elders and invalids in avoiding tumble, the posture variation
of unbalance and regaining balance motion are recorded by the
motion-capture image system, and the trajectory is taken as the desire
one. Then we calculate the force and moment of each joint based on
the leg motion model through programming MATLAB code. The
results would be primary information of the active leg orthosis design
for tumble protection.
Abstract: Covering approximation spaces is a class of important
generalization of approximation spaces. For a subset X of a covering
approximation space (U, C), is X definable or rough? The
answer of this question is uncertain, which depends on covering
approximation operators endowed on (U, C). Note that there are many
various covering approximation operators, which can be endowed
on covering approximation spaces. This paper investigates covering
approximation spaces endowed ten covering approximation operators
respectively, and establishes some relations among definable subsets,
inner definable subsets and outer definable subsets in covering approximation
spaces, which deepens some results on definable subsets
in approximation spaces.
Abstract: The main purpose of this study is to analyze the
relationship of leisure agriculture park visitors on tourist destination
image, environmental perception, travel experiences and revisiting
willingness. This study used questionnaires to Xinshe leisure
agriculture park visitors- targeted convenience sampling manner total
of 636 valid questionnaires. Valid questionnaires by descriptive
statistics, correlation analysis and multiple regression analysis, the
study found that: 1. The agricultural park visitors- correlations exist
between the destination image, perception of the environment, tourism
experience and revisiting willingness. 2."Excellent facilities and
services", "space atmosphere comfortable" and "the spacious paternity
outdoor space" imagery, of visitors- "revisiting willingness predict. 3.
Visitors- in leisure agriculture park "environmental perception" and
"travel experience, future revisiting willingness predict. According to
the analysis of the results, the study not only operate on the
recommendations of the leisure farm owners also provide follow-up
study direction for future researchers.
Abstract: This paper proposes a novel game theoretical
technique to address the problem of data object replication in largescale
distributed computing systems. The proposed technique draws
inspiration from computational economic theory and employs the
extended Vickrey auction. Specifically, players in a non-cooperative
environment compete for server-side scarce memory space to
replicate data objects so as to minimize the total network object
transfer cost, while maintaining object concurrency. Optimization of
such a cost in turn leads to load balancing, fault-tolerance and
reduced user access time. The method is experimentally evaluated
against four well-known techniques from the literature: branch and
bound, greedy, bin-packing and genetic algorithms. The experimental
results reveal that the proposed approach outperforms the four
techniques in both the execution time and solution quality.
Abstract: One of the main concerns about parallel mechanisms
is the presence of singular points within their workspaces. In singular
positions the mechanism gains or loses one or several degrees of
freedom. It is impossible to control the mechanism in singular
positions. Therefore, these positions have to be avoided. This is a
vital need especially in computer controlled machine tools designed
and manufactured on the basis of parallel mechanisms. This need has
to be taken into consideration when selecting design parameters. A
prerequisite to this is a thorough knowledge about the effect of
design parameters and constraints on singularity. In this paper,
quality condition index was introduced as a criterion for evaluating
singularities of different configurations of a hexapod mechanism
obtainable by different design parameters. It was illustrated that this
method can effectively be employed to obtain the optimum
configuration of hexapod mechanism with the aim of avoiding
singularity within the workspace. This method was then employed to
design the hexapod table of a CNC milling machine.
Abstract: We propose a novel graphical technique (SVision) for
intrusion detection, which pictures the network as a community of
hosts independently roaming in a 3D space defined by the set of
services that they use. The aim of SVision is to graphically cluster
the hosts into normal and abnormal ones, highlighting only the ones
that are considered as a threat to the network. Our experimental
results using DARPA 1999 and 2000 intrusion detection and
evaluation datasets show the proposed technique as a good candidate
for the detection of various threats of the network such as vertical
and horizontal scanning, Denial of Service (DoS), and Distributed
DoS (DDoS) attacks.
Abstract: The general idea behind the filter is to average a pixel
using other pixel values from its neighborhood, but simultaneously to
take care of important image structures such as edges. The main
concern of the proposed filter is to distinguish between any variations
of the captured digital image due to noise and due to image structure.
The edges give the image the appearance depth and sharpness. A
loss of edges makes the image appear blurred or unfocused.
However, noise smoothing and edge enhancement are traditionally
conflicting tasks. Since most noise filtering behaves like a low pass
filter, the blurring of edges and loss of detail seems a natural
consequence. Techniques to remedy this inherent conflict often
encompass generation of new noise due to enhancement.
In this work a new fuzzy filter is presented for the noise reduction
of images corrupted with additive noise. The filter consists of three
stages. (1) Define fuzzy sets in the input space to computes a fuzzy
derivative for eight different directions (2) construct a set of IFTHEN
rules by to perform fuzzy smoothing according to
contributions of neighboring pixel values and (3) define fuzzy sets in
the output space to get the filtered and edged image.
Experimental results are obtained to show the feasibility of the
proposed approach with two dimensional objects.
Abstract: In text categorization problem the most used method
for documents representation is based on words frequency vectors
called VSM (Vector Space Model). This representation is based only
on words from documents and in this case loses any “word context"
information found in the document. In this article we make a
comparison between the classical method of document representation
and a method called Suffix Tree Document Model (STDM) that is
based on representing documents in the Suffix Tree format. For the
STDM model we proposed a new approach for documents
representation and a new formula for computing the similarity
between two documents. Thus we propose to build the suffix tree
only for any two documents at a time. This approach is faster, it has
lower memory consumption and use entire document representation
without using methods for disposing nodes. Also for this method is
proposed a formula for computing the similarity between documents,
which improves substantially the clustering quality. This
representation method was validated using HAC - Hierarchical
Agglomerative Clustering. In this context we experiment also the
stemming influence in the document preprocessing step and highlight
the difference between similarity or dissimilarity measures to find
“closer" documents.
Abstract: Partitions can play a significant role in minimising cochannel
interference of Wireless LANs by attenuating signals across
room boundaries. This could pave the way towards higher density
deployments in home and office environments through spatial
channel reuse. Yet, due to protocol limitations, the latest incantation
of IEEE 802.11 standard is still unable to take advantage of this fact:
Despite having clearly adequate Signal to Interference Ratio (SIR)
over co-channel neighbouring networks in other rooms, its goodput
falls significantly lower than its maximum in the absence of cochannel
interferers. In this paper, we describe how this situation can
be remedied via modest modifications to the standard.