Abstract: This paper is concerned with the permanence and extinction problem of enterprises cluster constituted by m satellite enterprises and a dominant enterprise. We present the model involving impulsive effect based on ecology theory, which effectively describe the competition and cooperation of enterprises cluster in real economic environment. Applying comparison theorem of impulsive differential equation, we establish sufficient conditions which ultimately affect the fate of enterprises: permanence, extinction, and co-existence. Finally, we present numerical examples to explain the economical significance of mathematical results.
Abstract: SoftBoost is a recently presented boosting algorithm,
which trades off the size of achieved classification margin and
generalization performance. This paper presents a performance
evaluation of SoftBoost algorithm on the generic object recognition
problem. An appearance-based generic object recognition
model is used. The evaluation experiments are performed using
a difficult object recognition benchmark. An assessment with respect
to different degrees of label noise as well as a comparison to
the well known AdaBoost algorithm is performed. The obtained
results reveal that SoftBoost is encouraged to be used in cases
when the training data is known to have a high degree of noise.
Otherwise, using Adaboost can achieve better performance.
Abstract: This paper presents a formant-tracking linear prediction
(FTLP) model for speech processing in noise. The main focus of this
work is the detection of formant trajectory based on Hidden Markov
Models (HMM), for improved formant estimation in noise. The
approach proposed in this paper provides a systematic framework for
modelling and utilization of a time- sequence of peaks which satisfies
continuity constraints on parameter; the within peaks are modelled
by the LP parameters. The formant tracking LP model estimation
is composed of three stages: (1) a pre-cleaning multi-band spectral
subtraction stage to reduce the effect of residue noise on formants
(2) estimation stage where an initial estimate of the LP model of
speech for each frame is obtained (3) a formant classification using
probability models of formants and Viterbi-decoders. The evaluation
results for the estimation of the formant tracking LP model tested
in Gaussian white noise background, demonstrate that the proposed
combination of the initial noise reduction stage with formant tracking
and LPC variable order analysis, results in a significant reduction in
errors and distortions. The performance was evaluated with noisy
natual vowels extracted from international french and English vocabulary
speech signals at SNR value of 10dB. In each case, the
estimated formants are compared to reference formants.
Abstract: In the current research, we present an operation framework and protection mechanism to facilitate secure environment to protect mobile agents against tampering. The system depends on the presence of an authentication authority. The advantage of the proposed system is that security measures is an integral part of the design, thus common security retrofitting problems do not arise. This is due to the presence of AlGamal encryption mechanism to protect its confidential content and any collected data by the agent from the visited host . So that eavesdropping on information from the agent is no longer possible to reveal any confidential information. Also the inherent security constraints within the framework allow the system to operate as an intrusion detection system for any mobile agent environment. The mechanism is tested for most of the well known severe attacks against agents and networked systems. The scheme proved a promising performance that makes it very much recommended for the types of transactions that needs highly secure environments, e. g., business to business.
Abstract: In this paper, the modelling and design of artificial neural network architecture for load forecasting purposes is investigated. The primary pre-requisite for power system planning is to arrive at realistic estimates of future demand of power, which is known as Load Forecasting. Short Term Load Forecasting (STLF) helps in determining the economic, reliable and secure operating strategies for power system. The dependence of load on several factors makes the load forecasting a very challenging job. An over estimation of the load may cause premature investment and unnecessary blocking of the capital where as under estimation of load may result in shortage of equipment and circuits. It is always better to plan the system for the load slightly higher than expected one so that no exigency may arise. In this paper, a load-forecasting model is proposed using a multilayer neural network with an appropriately modified back propagation learning algorithm. Once the neural network model is designed and trained, it can forecast the load of the power system 24 hours ahead on daily basis and can also forecast the cumulative load on daily basis. The real load data that is used for the Artificial Neural Network training was taken from LDC, Gujarat Electricity Board, Jambuva, Gujarat, India. The results show that the load forecasting of the ANN model follows the actual load pattern more accurately throughout the forecasted period.
Abstract: Prolonged immobilization leads to significant
weakness and atrophy of the skeletal muscle and can also impair the
recovery of muscle strength following injury. Therefore, it is
important to minimize the period under immobilization and accelerate
the return to normal activity. This study examined the effects of heat
treatment and rest-inserted exercise on the muscle activity of the lower
limb during knee flexion/extension. Twelve healthy subjects were
assigned to 4 groups that included: (1) heat treatment + rest-inserted
exercise; (2) heat + continuous exercise; (3) no heat + rest-inserted
exercise; and (4) no heat + continuous exercise. Heat treatment was
applied for 15 mins prior to exercise. Continuous exercise groups
performed knee flexion/extension at 0.5 Hz for 300 cycles without rest
whereas rest-inserted exercise groups performed the same exercise but
with 2 mins rest inserted every 60 cycles of continuous exercise.
Changes in the rectus femoris and hamstring muscle activities were
assessed at 0, 1, and 2 weeks of treatment by measuring the
electromyography signals of isokinetic maximum voluntary
contraction. Significant increases in both the rectus femoris and
hamstring muscles were observed after 2 weeks of treatment only
when both heat treatment and rest-inserted exercise were performed.
These results suggest that combination of various treatment techniques,
such as heat treatment and rest-inserted exercise, may expedite the
recovery of muscle strength following immobilization.
Abstract: This paper argues that a product development exercise
involves in addition to the conventional stages, several decisions
regarding other aspects. These aspects should be addressed
simultaneously in order to develop a product that responds to the
customer needs and that helps realize objectives of the stakeholders
in terms of profitability, market share and the like. We present a
framework that encompasses these different development
dimensions. The framework shows that a product development
methodology such as the Quality Function Deployment (QFD) is the
basic tool which allows definition of the target specifications of a
new product. Creativity is the first dimension that enables the
development exercise to live and end successfully. A number of
group processes need to be followed by the development team in
order to ensure enough creativity and innovation. Secondly,
packaging is considered to be an important extension of the product.
Branding strategies, quality and standardization requirements,
identification technologies, design technologies, production
technologies and costing and pricing are also integral parts to the
development exercise. These dimensions constitute the proposed
framework. The paper also presents a mathematical model used to
calculate the design targets based on the target costing principle. The
framework is used to study a case of a new product development in
the telecommunications services sector.
Abstract: Stochastic resonance (SR) is a phenomenon whereby
the signal transmission or signal processing through certain nonlinear
systems can be improved by adding noise. This paper discusses SR in
nonlinear signal detection by a simple test statistic, which can be
computed from multiple noisy data in a binary decision problem based
on a maximum a posteriori probability criterion. The performance of
detection is assessed by the probability of detection error Per . When
the input signal is subthreshold signal, we establish that benefit from
noise can be gained for different noises and confirm further that the
subthreshold SR exists in nonlinear signal detection. The efficacy of
SR is significantly improved and the minimum of Per can
dramatically approach to zero as the sample number increases. These
results show the robustness of SR in signal detection and extend the
applicability of SR in signal processing.
Abstract: Fake finger submission attack is a major problem in fingerprint recognition systems. In this paper, we introduce an aliveness detection method based on multiple static features, which derived from a single fingerprint image. The static features are comprised of individual pore spacing, residual noise and several first order statistics. Specifically, correlation filter is adopted to address individual pore spacing. The multiple static features are useful to reflect the physiological and statistical characteristics of live and fake fingerprint. The classification can be made by calculating the liveness scores from each feature and fusing the scores through a classifier. In our dataset, we compare nine classifiers and the best classification rate at 85% is attained by using a Reduced Multivariate Polynomial classifier. Our approach is faster and more convenient for aliveness check for field applications.
Abstract: In this paper we present the information life cycle and analyze the importance of managing the corporate application portfolio across this life cycle. The approach presented here corresponds not just to the extension of the traditional information system development life cycle. This approach is based in the generic life cycle. In this paper it is proposed a model of an information system life cycle, supported in the assumption that a system has a limited life. But, this limited life may be extended. This model is also applied in several cases; being reported here two examples of the framework application in a construction enterprise and in a manufacturing enterprise.
Abstract: Noise has adverse effect on human health and
comfort. Noise not only cause hearing impairment, but it also acts as
a causal factor for stress and raising systolic pressure. Additionally it
can be a causal factor in work accidents, both by marking hazards
and warning signals and by impeding concentration. Industry
workers also suffer psychological and physical stress as well as
hearing loss due to industrial noise. This paper proposes an approach
to enable engineers to point out quantitatively the noisiest source for
modification, while multiple machines are operating simultaneously.
The model with the point source and spherical radiation in a free field
was adopted to formulate the problem. The procedure works very
well in ideal cases (point source and free field). However, most of the
industrial noise problems are complicated by the fact that the noise is
confined in a room. Reflections from the walls, floor, ceiling, and
equipment in a room create a reverberant sound field that alters the
sound wave characteristics from those for the free field. So the model
was validated for relatively low absorption room at NIT Kurukshetra
Central Workshop. The results of validation pointed out that the
estimated sound power of noise sources under simultaneous
conditions were on lower side, within the error limits 3.56 - 6.35 %.
Thus suggesting the use of this methodology for practical
implementation in industry. To demonstrate the application of the
above analytical procedure for estimating the sound power of noise
sources under simultaneous operating conditions, a manufacturing
facility (Railway Workshop at Yamunanagar, India) having five
sound sources (machines) on its workshop floor is considered in this
study. The findings of the case study had identified the two most
effective candidates (noise sources) for noise control in the Railway
Workshop Yamunanagar, India. The study suggests that the
modification in the design and/or replacement of these two identified
noisiest sources (machine) would be necessary so as to achieve an
effective reduction in noise levels. Further, the estimated data allows
engineers to better understand the noise situations of the workplace
and to revise the map when changes occur in noise level due to a
workplace re-layout.
Abstract: Insufficient Quality of Service (QoS) of Voice over
Internet Protocol (VoIP) is a growing concern that has lead the need
for research and study. In this paper we investigate the performance
of VoIP and the impact of resource limitations on the performance of
Access Networks. The impact of VoIP performance in Access
Networks is particularly important in regions where Internet
resources are limited and the cost of improving these resources is
prohibitive. It is clear that perceived VoIP performance, as measured
by mean opinion score [2] in experiments, where subjects are asked
to rate communication quality, is determined by end-to-end delay on
the communication path, delay variation, packet loss, echo, the
coding algorithm in use and noise. These performance indicators can
be measured and the affect in the Access Network can be estimated.
This paper investigates the congestion in the Access Network to the
overall performance of VoIP services with the presence of other
substantial uses of internet and ways in which Access Networks can
be designed to improve VoIP performance. Methods for analyzing
the impact of the Access Network on VoIP performance will be
surveyed and reviewed. This paper also considers some approaches
for improving performance of VoIP by carrying out experiments
using Network Simulator version 2 (NS2) software with a view to
gaining a better understanding of the design of Access Networks.
Abstract: In high powered dense wavelength division
multiplexed (WDM) systems with low chromatic dispersion,
four-wave mixing (FWM) can prove to be a major source of noise.
The MultiCanonical Monte Carlo Method (MCMC) and the Split
Step Fourier Method (SSFM) are combined to accurately evaluate the
probability density function of the decision variable of a receiver,
limited by FWM. The combination of the two methods leads to more
accurate results, and offers the possibility of adding other optical
noises such as the Amplified Spontaneous Emission (ASE) noise.
Abstract: A subcarrier - spectral amplitude coding optical code
division multiple access system using the Khazani-Syed code with
Complementary subtraction detection technique is proposed. The
proposed system has been analyzed by taking into account the effects
of phase-induced intensity noise, shot noise, thermal noise and intermodulation
distortion noise. The performance of the system has been
compared with the spectral amplitude coding optical code division
multiple access system using the Hadamard code and the Modified
Quadratic Congruence code. The analysis shows that the proposed
system can eliminate the multiple access interference using the
Complementary subtraction detection technique, and hence improve
the overall system performance.
Abstract: In the 21. century it comes true, that competitiveness of the firm is - to a considerable level - influenced by its participation in the chain of suppliers, customers and partners and by the way how the subject cooperates in the chain. This is valid also for new forms of enterprise such as virtual organization or virtual firm. In the first part of the paper there are determined the differences between these forms of enterprise. Another part will bring methodological framework for analysis of the factors, that influence the competitiveness of the virtual organization from spontaneity and order point of view.
Abstract: The third generation (3G) of cellular system adopted
the spread spectrum as solution for the transmission of the data in the
physical layer. Contrary to systems IS-95 or CDMAOne (systems
with spread spectrum of the preceding generation), the new standard,
called Universal Mobil Telecommunications System (UMTS), uses
long codes in the down link. The system is conceived for the vocal
communication and the transmission of the data. In particular, the
down link is very important, because of the asymmetrical request of
the data, i.e., more remote loading towards the mobiles than towards
the basic station. Moreover, the UMTS uses for the down link an
orthogonal spreading out with a variable factor of spreading out
(OVSF for Orthogonal Variable Spreading Factor). This
characteristic makes it possible to increase the flow of data of one or
more users by reducing their factor of spreading out without
changing the factor of spreading out of other users. In the current
standard of the UMTS, two techniques to increase the performances
of the down link were proposed, the diversity of sending antenna and
the codes space-time. These two techniques fight only fainding. The
receiver proposed for the mobil station is the RAKE, but one can
imagine a receiver more sophisticated, able to reduce the interference
between users and the impact of the coloured noise and interferences
to narrow band. In this context, where the users have long codes
synchronized with variable factor of spreading out and ignorance by
the mobile of the other active codes/users, the use of the sequences of
code pseudo-noises different lengths is presented in the form of one
of the most appropriate solutions.
Abstract: Support Vector Machine (SVM) is a statistical learning tool that was initially developed by Vapnik in 1979 and later developed to a more complex concept of structural risk minimization (SRM). SVM is playing an increasing role in applications to detection problems in various engineering problems, notably in statistical signal processing, pattern recognition, image analysis, and communication systems. In this paper, SVM was applied to the detection of medical ultrasound images in the presence of partially developed speckle noise. The simulation was done for single look and multi-look speckle models to give a complete overlook and insight to the new proposed model of the SVM-based detector. The structure of the SVM was derived and applied to clinical ultrasound images and its performance in terms of the mean square error (MSE) metric was calculated. We showed that the SVM-detected ultrasound images have a very low MSE and are of good quality. The quality of the processed speckled images improved for the multi-look model. Furthermore, the contrast of the SVM detected images was higher than that of the original non-noisy images, indicating that the SVM approach increased the distance between the pixel reflectivity levels (detection hypotheses) in the original images.
Abstract: A filter is used to remove undesirable frequency information from a dynamic signal. This paper shows that the Znotch filter filtering technique can be applied to remove the noise nuisance from a machining signal. In machining, the noise components were identified from the sound produced by the operation of machine components itself such as hydraulic system, motor, machine environment and etc. By correlating the noise components with the measured machining signal, the interested components of the measured machining signal which was less interfered by the noise, can be extracted. Thus, the filtered signal is more reliable to be analysed in terms of noise content compared to the unfiltered signal. Significantly, the I-kaz method i.e. comprises of three dimensional graphical representation and I-kaz coefficient, Z∞ could differentiate between the filtered and the unfiltered signal. The bigger space of scattering and the higher value of Z∞ demonstrated that the signal was highly interrupted by noise. This method can be utilised as a proactive tool in evaluating the noise content in a signal. The evaluation of noise content is very important as well as the elimination especially for machining operation fault diagnosis purpose. The Z-notch filtering technique was reliable in extracting noise component from the measured machining signal with high efficiency. Even though the measured signal was exposed to high noise disruption, the signal generated from the interaction between cutting tool and work piece still can be acquired. Therefore, the interruption of noise that could change the original signal feature and consequently can deteriorate the useful sensory information can be eliminated.
Abstract: This research focuses on the use of a recommender
system in decision support by means of a used car dealer case study
in Bangkok Metropolitan. The goal is to develop an effective used car
purchasing system for dealers based on the above premise. The
underlying principle rests on content-based recommendation from a
set of usability surveys. A prototype was developed to conduct
buyers- survey selected from 5 experts and 95 general public. The
responses were analyzed to determine the mean and standard
deviation of buyers- preference. The results revealed that both groups
were in favor of using the proposed system to assist their buying
decision. This indicates that the proposed system is meritorious to
used car dealers.
Abstract: One of the primary uses of higher order statistics in
signal processing has been for detecting and estimation of non-
Gaussian signals in Gaussian noise of unknown covariance. This is
motivated by the ability of higher order statistics to suppress additive
Gaussian noise. In this paper, several methods to test for non-
Gaussianity of a given process are presented. These methods include
histogram plot, kurtosis test, and hypothesis testing using cumulants
and bispectrum of the available sequence. The hypothesis testing is
performed by constructing a statistic to test whether the bispectrum
of the given signal is non-zero. A zero bispectrum is not a proof of
Gaussianity. Hence, other tests such as the kurtosis test should be
employed. Examples are given to demonstrate the performance of the
presented methods.