Abstract: This paper presents a signal analysis process for
improving energy completeness based on the Hilbert-Huang
Transform (HHT). Firstly, the vibration signal of a DC Motor obtained
by employing an accelerometer is the model used to analyze the
signal. Secondly, the intrinsic mode functions (IMFs) and Hilbert
spectrum of the decomposed signal are obtained by applying HHT.
The results of the IMFs constituent and the original signal are
compared and the process of energy loss is discussed. Finally, the
differences between Wavelet Transform (WT) and HHT in analyzing
the signal are compared. The simulated results reveal the analysis
process based on HHT is advantageous for the enhancement of energy
completeness.
Abstract: In this paper we present an enhanced noise reduction method for robust speech recognition using Adaptive Gain Equalizer with Non linear Spectral Subtraction. In Adaptive Gain Equalizer method (AGE), the input signal is divided into a number of subbands that are individually weighed in time domain, in accordance to the short time Signal-to-Noise Ratio (SNR) in each subband estimation at every time instant. Instead of focusing on suppression the noise on speech enhancement is focused. When analysis was done under various noise conditions for speech recognition, it was found that Adaptive Gain Equalizer method algorithm has an obvious failing point for a SNR of -5 dB, with inadequate levels of noise suppression for SNR less than this point. This work proposes the implementation of AGE when coupled with Non linear Spectral Subtraction (AGE-NSS) for robust speech recognition. The experimental result shows that out AGE-NSS performs the AGE when SNR drops below -5db level.
Abstract: This article presents a resistorless current-mode firstorder allpass filter based on second generation current controlled current conveyors (CCCIIs). The features of the circuit are that: the pole frequency can be electronically controlled via the input bias current: the circuit description is very simple, consisting of 2 CCCIIs and single grounded capacitor, without any external resistors and component matching requirements. Consequently, the proposed circuit is very appropriate to further develop into an integrated circuit. Low input and high output impedances of the proposed configuration enable the circuit to be cascaded in current-mode without additional current buffers. The PSpice simulation results are depicted. The given results agree well with the theoretical anticipation. The application example as a current-mode quadrature oscillator is included.
Abstract: Three new algorithms based on minimization of autocorrelation of transmitted symbols and the SLM approach which are computationally less demanding have been proposed. In the first algorithm, autocorrelation of complex data sequence is minimized to a value of 1 that results in reduction of PAPR. Second algorithm generates multiple random sequences from the sequence generated in the first algorithm with same value of autocorrelation i.e. 1. Out of these, the sequence with minimum PAPR is transmitted. Third algorithm is an extension of the second algorithm and requires minimum side information to be transmitted. Multiple sequences are generated by modifying a fixed number of complex numbers in an OFDM data sequence using only one factor. The multiple sequences represent the same data sequence and the one giving minimum PAPR is transmitted. Simulation results for a 256 subcarrier OFDM system show that significant reduction in PAPR is achieved using the proposed algorithms.
Abstract: In this paper, a novel feature-based image
watermarking scheme is proposed. Zernike moments which have
invariance properties are adopted in the scheme. In the proposed
scheme, feature points are first extracted from host image and several
circular patches centered on these points are generated. The patches
are used as carriers of watermark information because they can be
regenerated to locate watermark embedding positions even when
watermarked images are severely distorted. Zernike transform is then
applied to the patches to calculate local Zernike moments. Dither
modulation is adopted to quantize the magnitudes of the Zernike
moments followed by false alarm analysis. Experimental results show
that quality degradation of watermarked image is visually
transparent. The proposed scheme is very robust against image
processing operations and geometric attacks.
Abstract: Current trends in manufacturing are characterized by
production broadening, innovation cycle shortening, and the products
having a new shape, material and functions. The production strategy
focused on time needed change from the traditional functional
production structure to flexible manufacturing cells and lines.
Production by automated manufacturing system (AMS) is one of the
most important manufacturing philosophies in the last years. The
main goals of the project we are involved in lies on building a
laboratory in which will be located a flexible manufacturing system
consisting of at least two production machines with NC control
(milling machines, lathe). These machines will be linked to a
transport system and they will be served by industrial robots. Within
this flexible manufacturing system a station for the quality control
consisting of a camera system and rack warehouse will be also
located. The design, analysis and improvement of this manufacturing
system, specially with a special focus on the communication among
devices constitute the main aims of this paper. The key determining
factors for the manufacturing system design are: the product, the
production volume, the used machines, the disposable manpower, the
disposable infrastructure and the legislative frame for the specific
cases.
Abstract: This paper reviews recent studies and particularly the
effects of Climate Change in the North Tropical Atlantic by studying
atmospheric conditions that prevailed in 2005 ; Coral Bleaching
HotSpot and Hurricane Katrina. In the aim to better understand and
estimate the impact of the physical phenomenon, i.e. Thermal
Oceanic HotSpot (TOHS), isotopic studies of δ18O and δ13C on
marine animals from Guadeloupe (French Caribbean Island) were
carried out. Recorded measures show Sea Surface Temperature (SST)
up to 35°C in August which is much higher than data recorded by
NOAA satellites 32°C. After having reviewed the process that led to
the creation of Hurricane Katrina which hit New Orleans in August
29, 2005, it will be shown that the climatic conditions in the
Caribbean from August to October 2005 have influenced Katrina
evolution. This TOHS is a combined effect of various phenomenon
which represent an additional factor to estimate future climate
changes.
Abstract: A linear system is called a fully fuzzy linear system (FFLS) if quantities in this system are all fuzzy numbers. For the FFLS, we investigate its solution and develop a new approximate method for solving the FFLS. Observing the numerical results, we find that our method is accurate than the iterative Jacobi and Gauss- Seidel methods on approximating the solution of FFLS.
Abstract: In this work a new platform for mobile-health systems is
presented. System target application is providing decision support to
rescue corps or military medical personnel in combat areas. Software
architecture relies on a distributed client-server system that manages a
wireless ad-hoc networks hierarchy in which several different types of
client operate. Each client is characterized for different hardware and
software requirements. Lower hierarchy levels rely in a network of
completely custom devices that store clinical information and patient
status and are designed to form an ad-hoc network operating in the
2.4 GHz ISM band and complying with the IEEE 802.15.4 standard
(ZigBee). Medical personnel may interact with such devices, that are
called MICs (Medical Information Carriers), by means of a PDA
(Personal Digital Assistant) or a MDA (Medical Digital Assistant),
and transmit the information stored in their local databases as well as
issue a service request to the upper hierarchy levels by using IEEE
802.11 a/b/g standard (WiFi). The server acts as a repository that
stores both medical evacuation forms and associated events (e.g., a
teleconsulting request). All the actors participating in the diagnostic
or evacuation process may access asynchronously to such repository
and update its content or generate new events. The designed system
pretends to optimise and improve information spreading and flow
among all the system components with the aim of improving both
diagnostic quality and evacuation process.
Abstract: The paper deals with cartographic visualisation of
results of transport accessibility monitoring with the use of a semiautomated
method of unipolar anamorphosis, developed by the
authors in the GIS environment. The method is based on
transformation of distance in the map to values of a geographical
phenomenon. In the case of time accessibility it is based on
transformation of isochrones converted into the form of concentric
circles, taking into account selected topographic and thematic
elements in the map. The method is most suitable for analyses of
accessibility to or from a centre and for modelling its long-term
context.
The paper provides a detailed analysis of the procedures and
functionality of the method, discussing the issues of coordinates,
transformation, scale and visualisation. It also offers a discussion of
possible problems and inaccuracies. A practical application of the
method is illustrated by previous research results by the authors in
the filed of accessibility in Czechia.
Abstract: Time series analysis often requires data that represents
the evolution of an observed variable in equidistant time steps. In
order to collect this data sampling is applied. While continuous
signals may be sampled, analyzed and reconstructed applying
Shannon-s sampling theorem, time-discrete signals have to be dealt
with differently. In this article we consider the discrete-event
simulation (DES) of job-shop-systems and study the effects of
different sampling rates on data quality regarding completeness and
accuracy of reconstructed inventory evolutions. At this we discuss
deterministic as well as non-deterministic behavior of system
variables. Error curves are deployed to illustrate and discuss the
sampling rate-s impact and to derive recommendations for its wellfounded
choice.
Abstract: This paper examines whether or not immigration has a positive influence on the duration of unemployment, in a macroeconomic perspective. We analyse also whether the degree of labor market integration can influence migration. The integration of immigrants into the labor market is a recurrence theme in the work on the economic consequences of immigration. However, to our knowledge, no researchers have studied the impact of immigration on unemployment duration, and vice versa. With two methodology of research (panel estimations (OLS and 2SLS) and panel cointegration techniques), we show that migration seems to influence positively the short-term unemployment and negatively long-term unemployment, for 14 OECD destination countries. In addition, immigration seems to be conditioned by the structural and institutional characteristics of the labour market.
Abstract: A semi-active control strategy for suspension
systems of passenger cars is presented employing
Magnetorheological (MR) dampers. The vehicle is modeled with
seven DOFs including the, roll pitch and bounce of car body, and
the vertical motion of the four tires. In order to design an optimal
controller based on the actuator constraints, a Linear-Quadratic
Regulator (LQR) is designed. The design procedure of the LQR
consists of selecting two weighting matrices to minimize the energy
of the control system. This paper presents a hybrid optimization
procedure which is a combination of gradient-based and
evolutionary algorithms to choose the weighting matrices with
regards to the actuator constraint. The optimization algorithm is
defined based on maximum comfort and actuator constraints. It is
noted that utilizing the present control algorithm may significantly
reduce the vibration response of the passenger car, thus, providing
a comfortable ride.
Abstract: Support vector machines (SVMs) are considered to be
the best machine learning algorithms for minimizing the predictive
probability of misclassification. However, their drawback is that for
large data sets the computation of the optimal decision boundary is a
time consuming function of the size of the training set. Hence several
methods have been proposed to speed up the SVM algorithm. Here
three methods used to speed up the computation of the SVM
classifiers are compared experimentally using a musical genre
classification problem. The simplest method pre-selects a random
sample of the data before the application of the SVM algorithm. Two
additional methods use proximity graphs to pre-select data that are
near the decision boundary. One uses k-Nearest Neighbor graphs and
the other Relative Neighborhood Graphs to accomplish the task.
Abstract: The posteroanterior manipulation technique is usually include in the procedure of the lumbar spine to evaluate the intervertebral motion according to mechanical resistance. The mechanical device with visual feedback was proposed that allows one to analysis the lumbar segments mobility “in vivo" facilitating for the therapist to take its treatment evolution. The measuring system uses load cell and displacement sensor to estimate spine stiffness. In this work, the device was tested by 2 therapists, female, applying posteroanterior force techniques to 5 volunteers, female, with frequency of approximately 1.2-1.8 Hz. A test-retest procedure was used for 2 periods of day. The visual feedback results small variation of forces and cycle time during 6 cycles rhythmic application. The stiffness values showed good agreement between test-retest procedures when used same order of maximum forces.
Abstract: This paper presents a CFD analysis of the flow around
a 30° inclined flat plate of infinite span. Numerical predictions have
been compared to experimental measurements, in order to assess the
potential of the finite volume code of determining the aerodynamic
forces acting on a flat plate invested by a fluid stream of infinite
extent.
Several turbulence models and spatial node distributions have
been tested and flow field characteristics in the neighborhood of the
flat plate have been numerically investigated, allowing the
development of a preliminary procedure to be used as guidance in
selecting the appropriate grid configuration and the corresponding
turbulence model for the prediction of the flow field over a twodimensional
inclined plate.
Abstract: The Sensor Network consists of densely deployed
sensor nodes. Energy optimization is one of the most important
aspects of sensor application design. Data acquisition and aggregation
techniques for processing data in-network should be energy efficient.
Due to the cross-layer design, resource-limited and noisy nature
of Wireless Sensor Networks(WSNs), it is challenging to study
the performance of these systems in a realistic setting. In this
paper, we propose optimizing queries by aggregation of data and
data redundancy to reduce energy consumption without requiring
all sensed data and directed diffusion communication paradigm to
achieve power savings, robust communication and processing data
in-network. To estimate the per-node power consumption POWERTossim
mica2 energy model is used, which provides scalable and
accurate results. The performance analysis shows that the proposed
methods overcomes the existing methods in the aspects of energy
consumption in wireless sensor networks.
Abstract: A novel methodology has been used to design an
evaporator coil of a refrigerant. The methodology used is through a
complete Computer Aided Design /Computer Aided Engineering
approach, by means of a Computational Fluid Dynamic/Finite
Element Analysis model which is executed many times for the
thermal-fluid exploration of several designs' configuration by an
commercial optimizer. Hence the design is carried out automatically
by parallel computations, with an optimization package taking the
decisions rather than the design engineer. The engineer instead takes
decision regarding the physical settings and initializing of the
computational models to employ, the number and the extension of the
geometrical parameters of the coil fins and the optimization tools to
be employed. The final design of the coil geometry found to be better
than the initial design.
Abstract: This paper proposes evaluation of sound parameterization methods in recognizing some spoken Arabic words, namely digits from zero to nine. Each isolated spoken word is represented by a single template based on a specific recognition feature, and the recognition is based on the Euclidean distance from those templates. The performance analysis of recognition is based on four parameterization features: the Burg Spectrum Analysis, the Walsh Spectrum Analysis, the Thomson Multitaper Spectrum Analysis and the Mel Frequency Cepstral Coefficients (MFCC) features. The main aim of this paper was to compare, analyze, and discuss the outcomes of spoken Arabic digits recognition systems based on the selected recognition features. The results acqired confirm that the use of MFCC features is a very promising method in recognizing Spoken Arabic digits.
Abstract: This paper provides some thoughts about the lack of
attentiveness of building commissioning in the construction industry
and the lack of handling in project commissioning as an integral part
of the project life-cycle. Many have perceived commissioning as the
problem solving process of a project, rather than the start up of the
equipment, or the handing over of the project to the client. Therefore,
there is a lack of proper attention in the planning of commissioning
as a vital part of the project life-cycle. This review paper aims to
highlight the benefits of building commissioning and to propose the
lacking of knowledge gap on building commissioning. Finally, this
paper hopes to propose the shift of focus on this matter in future
research.