Abstract: In this paper, a new approach for target recognition based on the Empirical mode decomposition (EMD) algorithm of Huang etal. [11] and the energy tracking operator of Teager [13]-[14] is introduced. The conjunction of these two methods is called Teager-Huang analysis. This approach is well suited for nonstationary signals analysis. The impulse response (IR) of target is first band pass filtered into subsignals (components) called Intrinsic mode functions (IMFs) with well defined Instantaneous frequency (IF) and Instantaneous amplitude (IA). Each IMF is a zero-mean AM-FM component. In second step, the energy of each IMF is tracked using the Teager energy operator (TEO). IF and IA, useful to describe the time-varying characteristics of the signal, are estimated using the Energy separation algorithm (ESA) algorithm of Maragos et al .[16]-[17]. In third step, a set of features such as skewness and kurtosis are extracted from the IF, IA and IMF energy functions. The Teager-Huang analysis is tested on set of synthetic IRs of Sonar targets with different physical characteristics (density, velocity, shape,? ). PCA is first applied to features to discriminate between manufactured and natural targets. The manufactured patterns are classified into spheres and cylinders. One hundred percent of correct recognition is achieved with twenty three echoes where sixteen IRs, used for training, are free noise and seven IRs, used for testing phase, are corrupted with white Gaussian noise.
Abstract: In this work, we are interested in developing a speech denoising tool by using a discrete wavelet packet transform (DWPT). This speech denoising tool will be employed for applications of recognition, coding and synthesis. For noise reduction, instead of applying the classical thresholding technique, some wavelet packet nodes are set to zero and the others are thresholded. To estimate the non stationary noise level, we employ the spectral entropy. A comparison of our proposed technique to classical denoising methods based on thresholding and spectral subtraction is made in order to evaluate our approach. The experimental implementation uses speech signals corrupted by two sorts of noise, white and Volvo noises. The obtained results from listening tests show that our proposed technique is better than spectral subtraction. The obtained results from SNR computation show the superiority of our technique when compared to the classical thresholding method using the modified hard thresholding function based on u-law algorithm.
Abstract: The current education system in India is adept in
equipping and assessing the scholastic development of children.
However, there is an immediate need to strengthen co-scholastic
areas like life-skills, values and attitudes to equip students to face real
life challenges. Audio-visual technology and their respective media
can make a significant contribution to a value based learning
curriculum. Thus, co-scholastic skills need to be effectively nurtured
by a medium that is entertaining and impactful. Films in general have
a tremendous impact in our society. Films with a positive message
make a formidable learning experience that can influence and inspire
generations of learners. Leveraging on this powerful medium,
EduMedia India Pvt. Ltd. has introduced School Cinema a well
researched film-based learning module supported by a fun and
exciting workbook, designed to introduce and reaffirm life-skills and
values to children, thereby having a positive influence on their
attitudes.
Abstract: It is important problems to increase the detection rates
and reduce false positive rates in Intrusion Detection System (IDS).
Although preventative techniques such as access control and
authentication attempt to prevent intruders, these can fail, and as a
second line of defence, intrusion detection has been introduced. Rare
events are events that occur very infrequently, detection of rare
events is a common problem in many domains. In this paper we
propose an intrusion detection method that combines Rough set and
Fuzzy Clustering. Rough set has to decrease the amount of data and
get rid of redundancy. Fuzzy c-means clustering allow objects to
belong to several clusters simultaneously, with different degrees of
membership. Our approach allows us to recognize not only known
attacks but also to detect suspicious activity that may be the result of
a new, unknown attack. The experimental results on Knowledge
Discovery and Data Mining-(KDDCup 1999) Dataset show that the
method is efficient and practical for intrusion detection systems.
Abstract: This study examines the issue of recommendation
sources from the perspectives of gender and consumers- perceived
risk, and validates a model for the antecedents of consumer online
purchases. The method of obtaining quantitative data was that of the
instrument of a survey questionnaire. Data were collected via
questionnaires from 396 undergraduate students aged 18-24, and a
multiple regression analysis was conducted to identify causal
relationships. Empirical findings established the link between
recommendation sources (word-of-mouth, advertising, and
recommendation systems) and the likelihood of making online
purchases and demonstrated the role of gender and perceived risk as
moderators in this context. The results showed that the effects of
word-of-mouth on online purchase intentions were stronger than those
of advertising and recommendation systems. In addition, female
consumers have less experience with online purchases, so they may be
more likely than males to refer to recommendations during the
decision-making process. The findings of the study will help
marketers to address the recommendation factor which influences
consumers- intention to purchase and to improve firm performances to
meet consumer needs.
Abstract: In the past many uneconomic solutions for limitation
and interruption of short-circuit currents in low power applications
have been introduced, especially polymer switch based on the
positive temperature coefficient of resistance (PCTR) concept.
However there are many limitations in the active material, which
consists of conductive fillers. This paper presents a significantly
improved and simplified approach that replaces the existing current
limiters with faster switching elements. Its elegance lies in the
remarkable simplicity and low-cost processes of producing the device
using polyaniline (PANI) doped with methane-sulfonic acid (MSA).
Samples characterized as lying in the metallic and critical regimes of
metal insulator transition have been studied by means of electrical
performance in the voltage range from 1V to 5 V under different
environmental conditions. Moisture presence is shown to increase the
resistivity and also improved its current limiting performance.
Additionally, the device has also been studied for electrical resistivity
in the temperature range 77 K-300 K. The temperature dependence of
the electrical conductivity gives evidence for a transport mechanism
based on variable range hopping in three dimensions.
Abstract: The behavior of Radial Basis Function (RBF) Networks greatly depends on how the center points of the basis functions are selected. In this work we investigate the use of instance reduction techniques, originally developed to reduce the storage requirements of instance based learners, for this purpose. Five Instance-Based Reduction Techniques were used to determine the set of center points, and RBF networks were trained using these sets of centers. The performance of the RBF networks is studied in terms of classification accuracy and training time. The results obtained were compared with two Radial Basis Function Networks: RBF networks that use all instances of the training set as center points (RBF-ALL) and Probabilistic Neural Networks (PNN). The former achieves high classification accuracies and the latter requires smaller training time. Results showed that RBF networks trained using sets of centers located by noise-filtering techniques (ALLKNN and ENN) rather than pure reduction techniques produce the best results in terms of classification accuracy. The results show that these networks require smaller training time than that of RBF-ALL and higher classification accuracy than that of PNN. Thus, using ALLKNN and ENN to select center points gives better combination of classification accuracy and training time. Our experiments also show that using the reduced sets to train the networks is beneficial especially in the presence of noise in the original training sets.
Abstract: The non-destructive testing of launch tube weld with
radiography was investigated and evaluated with AWS D1.1
standard. The paper started with preparation of launch tube and
radiographic inspection. X-Ray inspection then was done and gotten
the result. The judgment of inspection results were concluded by
certified person and finally, the evaluation with AWS D1.1 standard
was conducted as well.
The result shown that weld position P1 was not conformed to
AWS D1.1 which allowed size of incomplete penetration did not
exceed 4 mm. The other welds were corresponded to as mentioned
standard. Additionally, the corrective actions for incomplete
penetration either provided for future actions.
Abstract: The aim of the work was to attenuate the vibration amplitude in CESNA 172 airplane wing by using Functionally Graded Material instead of uniform or composite material. Wing strength was achieved by means of stress analysis study, while wing vibration amplitudes and shapes were achieved by means of Modal and Harmonic analysis. Results were verified by applying the methodology in a simple cantilever plate to the simple model and the results were promising and the same methodology can be applied to the airplane wing model. Aluminum models, Titanium models, and functionally graded materials of Aluminum and titanium results were compared to show a great vibration attenuation after using the FGM. Optimization in FGM gradation satisfied our objective of reducing and attenuating the vibration amplitudes to show the effect of using FGM in vibration behavior. Testing the Aluminum rich models, and comparing it with the titanium rich model was an optimization in this paper. Results have shown a significant attenuation in vibration magnitudes when using FGM instead of Titanium Plate, and Aluminium wing with FGM Spurs instead of Aluminium wings. It was also recommended that in future, changing the graphical scale to 1:10 or even 1:1 when the computers- capabilities allow.
Abstract: Feeder is one of the airships of the Multibody Advanced Airship for Transport (MAAT) system, under development within the EU FP7 project. MAAT is based on a modular concept composed of two different parts that have the possibility to join; respectively they are the so-called Cruiser and Feeder, designed on the lighter than air principle. Feeder, also named ATEN (Airship Transport Elevator Network), is the smaller one which joins the bigger one, Cruiser, also named PTAH (Photovoltaic modular Transport Airship for High altitude),envisaged to happen at 15km altitude. During the MAAT design phase, the aerodynamic studies of the both airships and their interactions are analyzed. The objective of these studies is to understand the aerodynamic behavior of all the preselected configurations, as an important element in the overall MAAT system design. The most of these configurations are only simulated by CFD, while the most feasible one is experimentally analyzed in order to validate and thrust the CFD predictions. This paper presents the numerical and experimental investigation of the Feeder “conical like" shape configuration. The experiments are focused on the aerodynamic force coefficients and the pressure distribution over the Feeder outer surface, while the numerical simulation cover also the analysis of the velocity and pressure distribution. Finally, the wind tunnel experiment is compared with its CFD model in order to validate such specific simulations with respective experiments and to better understand the difference between the wind tunnel and in-flight circumstances.
Abstract: In the present work, an attempt is made to understand
electromagnetic field confinement in a subwavelength waveguide
structure using concepts of quantum mechanics. Evanescent field in
the waveguide is looked as inability of the photon to get confined in
the waveguide core and uncertainty of position is assigned to it. The
momentum uncertainty is calculated from position uncertainty.
Schrödinger wave equation for the photon is written by incorporating
position-momentum uncertainty. The equation is solved and field
distribution in the waveguide is obtained. The field distribution and
power confinement is compared with conventional waveguide theory.
They were found in good agreement with each other.
Abstract: The present work represents an investigation of the
hydrolysis of hull-less pumpkin (Cucurbita Pepo L.) oil cake protein
isolate (PuOC PI) by pepsin. To examine the effectiveness and
suitability of pepsin towards PuOC PI the kinetic parameters for
pepsin on PuOC PI were determined and then, the hydrolysis process
was studied using Response Surface Methodology (RSM). The
hydrolysis was carried out at temperature of 30°C and pH 3.00. Time
and initial enzyme/substrate ratio (E/S) at three levels were selected
as the independent parameters. The degree of hydrolysis, DH, was
mesuared after 20, 30 and 40 minutes, at initial E/S of 0.7, 1 and 1.3
mA/mg proteins. Since the proposed second-order polynomial model
showed good fit with the experimental data (R2 = 0.9822), the
obtained mathematical model could be used for monitoring the
hydrolysis of PuOC PI by pepsin, under studied experimental
conditions, varying the time and initial E/S. To achieve the highest
value of DH (39.13 %), the obtained optimum conditions for time
and initial E/S were 30 min and 1.024 mA/mg proteins.
Abstract: e-mail has become an important means of electronic
communication but the viability of its usage is marred by Unsolicited
Bulk e-mail (UBE) messages. UBE consists of many types
like pornographic, virus infected and 'cry-for-help' messages as well
as fake and fraudulent offers for jobs, winnings and medicines. UBE
poses technical and socio-economic challenges to usage of e-mails.
To meet this challenge and combat this menace, we need to
understand UBE. Towards this end, the current paper presents a
content-based textual analysis of nearly 3000 winnings-announcing
UBE. Technically, this is an application of Text Parsing and
Tokenization for an un-structured textual document and we approach
it using Bag Of Words (BOW) and Vector Space Document Model
techniques. We have attempted to identify the most frequently
occurring lexis in the winnings-announcing UBE documents. The
analysis of such top 100 lexis is also presented. We exhibit the
relationship between occurrence of a word from the identified lexisset
in the given UBE and the probability that the given UBE will be
the one announcing fake winnings. To the best of our knowledge and
survey of related literature, this is the first formal attempt for
identification of most frequently occurring lexis in winningsannouncing
UBE by its textual analysis. Finally, this is a sincere
attempt to bring about alertness against and mitigate the threat of
such luring but fake UBE.
Abstract: This paper describes a methodology for remote
performance monitoring of retail refrigeration systems. The proposed
framework starts with monitoring of the whole refrigeration circuit
which allows detecting deviations from expected behavior caused by
various faults and degradations. The subsequent diagnostics methods
drill down deeper in the equipment hierarchy to more specifically
determine root causes. An important feature of the proposed concept
is that it does not require any additional sensors, and thus, the
performance monitoring solution can be deployed at a low
installation cost. Moreover only a minimum of contextual
information is required, which also substantially reduces time and
cost of the deployment process.
Abstract: A time-domain numerical model within the
framework of transmission line modeling (TLM) is developed to
simulate electromagnetic pulse propagation inside multiple
microcavities forming photonic crystal (PhC) structures. The model
developed is quite general and is capable of simulating complex
electromagnetic problems accurately. The field quantities can be
mapped onto a passive electrical circuit equivalent what ensures that
TLM is provably stable and conservative at a local level.
Furthermore, the circuit representation allows a high level of
hybridization of TLM with other techniques and lumped circuit
models of components and devices. A photonic crystal structure
formed by rods (or blocks) of high-permittivity dieletric material
embedded in a low-dielectric background medium is simulated as an
example. The model developed gives vital spatio-temporal
information about the signal, and also gives spectral information over
a wide frequency range in a single run. The model has wide
applications in microwave communication systems, optical
waveguides and electromagnetic materials simulations.
Abstract: High Performance Work Systems (HPWS) generally give rise to positive impacts on employees by increasing their commitments in workplaces. While some argued this actually have considerable negative impacts on employees with increasing possibilities of imposing strains caused by stress and intensity of such work places. Do stressful workplaces hamper employee commitment? The author has tried to find the answer by exploring linkages between HPWS practices and its impact on employees in Japanese organizations. How negative outcomes like job intensity and workplaces and job stressors can influence different forms of employees- commitments which can be a hindrance to their performance. Design: A close ended questionnaire survey was conducted amongst 16 large, medium and small sized Japanese companies from diverse industries around Chiba, Saitama, and Ibaraki Prefectures and in Tokyo from the month of October 2008 to February 2009. Questionnaires were aimed to the non managerial employees- perceptions of HPWS practices, their behavior, working life experiences in their work places. A total of 227 samples are used for analysis in the study. Methods: Correlations, MANCOVA, SEM Path analysis using AMOS software are used for data analysis in this study. Findings: Average non-managerial perception of HPWS adoption is significantly but negatively correlated to both work place Stressors and Continuous commitment, but positively correlated to job Intensity, Affective, Occupational and Normative commitments in different workplaces at Japan. The path analysis by SEM shows significant indirect relationship between Stressors and employee Affective organizational commitment and Normative organizational commitments. Intensity also has a significant indirect effect on Occupational commitments. HPWS has an additive effect on all the outcomes variables. Limitations: The sample size in this study cannot be a representative to the entire population of non-managerial employees in Japan. There were no respondents from automobile, pharmaceuticals, finance industries. The duration of the survey coincided in a period when Japan as most of the other countries is under going recession. Biases could not be ruled out completely. We must take cautions in interpreting the results of studies as they cannot be generalized. And the path analysis cannot provide the complete causality of the inter linkages between the variables used in the study. Originality: There have been limited studies on linkages in HPWS adoptions and their impacts on employees- behaviors and commitments in Japanese workplaces. This study may provide some ingredients for further research in the fields of HRM policies and practices and their linkages on different forms of employees- commitments.
Abstract: This paper presents initiatives of Knowledge
Management (KM) applied to Forensic Sciences field, especially
developed at the Forensic Science Institute of the Brazilian Federal
Police. Successful projects, related to knowledge sharing, drugs
analysis and environmental crimes, are reported in the KM
perspective. The described results are related to: a) the importance of
having an information repository, like a digital library, in such a
multidisciplinary organization; b) the fight against drug dealing and
environmental crimes, enabling the possibility to map the evolution
of crimes, drug trafficking flows, and the advance of deforestation in
Amazon rain forest. Perspectives of new KM projects under
development and studies are also presented, tracing an evolution line
of the KM view at the Forensic Science Institute.
Abstract: This paper presents optimal based damping controllers of Unified Power Flow Controller (UPFC) for improving the damping power system oscillations. The design problem of UPFC damping controller and system configurations is formulated as an optimization with time domain-based objective function by means of Adaptive Tabu Search (ATS) technique. The UPFC is installed in Single Machine Infinite Bus (SMIB) for the performance analysis of the power system and simulated using MATLAB-s simulink. The simulation results of these studies showed that designed controller has an tremendous capability in damping power system oscillations.
Abstract: Response surface methodology (RSM) is a very
efficient tool to provide a good practical insight into developing new
process and optimizing them. This methodology could help
engineers to raise a mathematical model to represent the behavior of
system as a convincing function of process parameters.
Through this paper the sequential nature of the RSM surveyed for process
engineers and its relationship to design of experiments (DOE), regression
analysis and robust design reviewed. The proposed four-step procedure in
two different phases could help system analyst to resolve the parameter
design problem involving responses. In order to check accuracy of the
designed model, residual analysis and prediction error sum of squares
(PRESS) described.
It is believed that the proposed procedure in this study can resolve a
complex parameter design problem with one or more responses. It can be
applied to those areas where there are large data sets and a number of
responses are to be optimized simultaneously. In addition, the proposed
procedure is relatively simple and can be implemented easily by using
ready-made standard statistical packages.
Abstract: This study examines the relationships between foreign
aid, levels of schooling and democracy for Pakistan using the ARDL
cointegration approach. The results of study provide strong evidence
for fairly robust long run as well as short run relationships among
these variables for the period 1973-2008. The results state that
foreign aid and primary school enrollments have negative impact on
democracy index and high school enrollments have positive impact
on democracy index in Pakistan. The study suggests for promotion of
education levels and relies on local resources instead of foreign aid
for a good quality of political institutions in Pakistan.