Abstract: In 1990 [1] the subband-DFT (SB-DFT) technique was proposed. This technique used the Hadamard filters in the decomposition step to split the input sequence into low- and highpass sequences. In the next step, either two DFTs are needed on both bands to compute the full-band DFT or one DFT on one of the two bands to compute an approximate DFT. A combination network with correction factors was to be applied after the DFTs. Another approach was proposed in 1997 [2] for using a special discrete wavelet transform (DWT) to compute the discrete Fourier transform (DFT). In the first step of the algorithm, the input sequence is decomposed in a similar manner to the SB-DFT into two sequences using wavelet decomposition with Haar filters. The second step is to perform DFTs on both bands to obtain the full-band DFT or to obtain a fast approximate DFT by implementing pruning at both input and output sides. In this paper, the wavelet-based DFT (W-DFT) with Haar filters is interpreted as SB-DFT with Hadamard filters. The only difference is in a constant factor in the combination network. This result is very important to complete the analysis of the W-DFT, since all the results concerning the accuracy and approximation errors in the SB-DFT are applicable. An application example in spectral analysis is given for both SB-DFT and W-DFT (with different filters). The adaptive capability of the SB-DFT is included in the W-DFT algorithm to select the band of most energy as the band to be computed. Finally, the W-DFT is extended to the two-dimensional case. An application in image transformation is given using two different types of wavelet filters.
Abstract: One of the main research directions in CAD/CAM
machining area is the reducing of machining time.
The feedrate scheduling is one of the advanced techniques that
allows keeping constant the uncut chip area and as sequel to keep
constant the main cutting force. They are two main ways for feedrate
optimization. The first consists in the cutting force monitoring, which
presumes to use complex equipment for the force measurement and
after this, to set the feedrate regarding the cutting force variation. The
second way is to optimize the feedrate by keeping constant the
material removal rate regarding the cutting conditions.
In this paper there is proposed a new approach using an extended
database that replaces the system model.
The feedrate scheduling is determined based on the identification
of the reconfigurable machine tool, and the feed value determination
regarding the uncut chip section area, the contact length between tool
and blank and also regarding the geometrical roughness.
The first stage consists in the blank and tool monitoring for the
determination of actual profiles. The next stage is the determination
of programmed tool path that allows obtaining the piece target
profile.
The graphic representation environment models the tool and blank
regions and, after this, the tool model is positioned regarding the
blank model according to the programmed tool path. For each of
these positions the geometrical roughness value, the uncut chip area
and the contact length between tool and blank are calculated. Each of
these parameters are compared with the admissible values and
according to the result the feed value is established.
We can consider that this approach has the following advantages:
in case of complex cutting processes the prediction of cutting force is
possible; there is considered the real cutting profile which has
deviations from the theoretical profile; the blank-tool contact length
limitation is possible; it is possible to correct the programmed tool
path so that the target profile can be obtained.
Applying this method, there are obtained data sets which allow the
feedrate scheduling so that the uncut chip area is constant and, as a
result, the cutting force is constant, which allows to use more
efficiently the machine tool and to obtain the reduction of machining
time.
Abstract: This article concerns the presentation of an integrated
method for detection of steganographic content embedded by new
unknown programs. The method is based on data mining and
aggregated hypothesis testing. The article contains the theoretical
basics used to deploy the proposed detection system and the
description of improvement proposed for the basic system idea.
Further main results of experiments and implementation details are
collected and described. Finally example results of the tests are
presented.
Abstract: Thermal behavior of fuel channel under loss of coolant accident (LOCA) is a major concern for nuclear reactor safety. LOCA along with failure of emergency cooling water system (ECC) may leads to mechanical deformations like sagging and ballooning. In order to understand the phenomenon an experiment has been carried out using 19 pin fuel element simulator. Main purpose of the experiment was to trace temperature profiles over the pressure tube, calandria tube and clad tubes of Indian Pressurized Heavy Water Reactor (IPHWR) under symmetrical and asymmetrical heat-up conditions. For simulating the fully voided scenario, symmetrical heating of pressure was carried out by injecting 13.2 KW (2 % of nominal power) to all the 19 pins and the temperatures of pressure tube, calandria tube and clad tubes were measured. During symmetrical heating the sagging of fuel channel was initiated at 460 °C and the highest temperature attained by PT was 650 °C . The decay heat from clad tubes was dissipated to moderator mainly by radiation and natural convection. The highest temperature of 680 °C was observed over the outer ring of clad tubes of fuel simulator. Again, to simulate partially voided condition, asymmetrical heating of pressure was carried out by supplying 8.0 kW power to upper 8 pins of fuel simulator and temperature profiles were measured. Along the circumference of pressure tube (PT) the highest temperature difference of 320 °C was observed, which highlights the magnitude of thermal stresses under partially voided conditions.
Abstract: The purpose of study is to demonstrate how the characteristics of technology and the process required for development of technology affect technology transfer from public organisations to industry on the technology level. In addition, using the advantage of the analytic level and the novel means of measuring technology convergence, we examine the characteristics of converging technologies as compared to non-converging technologies in technology transfer process. In sum, our study finds that a technology from the public sector is likely to be transferred when its readiness level is closer to generation of profit, when its stage of life cycle is early and when its economic values is high. Our findings also show that converging technologies are less likely to be transferred.
Abstract: The production of devices in nanoscale with specific
molecular rectifying function is one of the most significant goals in
state-of-art technology. In this work we show by ab initio quantum
mechanics calculations coupled with non-equilibrium Green
function, the design of an organic two-terminal device. These
molecular structures have molecular source and drain with several
bridge length (from five up to 11 double bonds). Our results are
consistent with significant features as a molecular rectifier and can be
raised up as: (a) it can be used as bi-directional symmetrical rectifier;
(b) two devices integrated in one (FET with one operational region,
and Thyristor thiristor); (c) Inherent stability due small intrinsic
capacitance under forward/reverse bias. We utilize a scheme for the
transport mechanism based on previous properties of ¤Ç bonds type
that can be successfully utilized to construct organic nanodevices.
Abstract: Scheduling for the flexible job shop is very important
in both fields of production management and combinatorial
optimization. However, it quit difficult to achieve an optimal solution
to this problem with traditional optimization approaches owing to the
high computational complexity. The combining of several
optimization criteria induces additional complexity and new
problems. In this paper, a Pareto approach to solve the multi
objective flexible job shop scheduling problems is proposed. The
objectives considered are to minimize the overall completion time
(makespan) and total weighted tardiness (TWT). An effective
simulated annealing algorithm based on the proposed approach is
presented to solve multi objective flexible job shop scheduling
problem. An external memory of non-dominated solutions is
considered to save and update the non-dominated solutions during
the solution process. Numerical examples are used to evaluate and
study the performance of the proposed algorithm. The proposed
algorithm can be applied easily in real factory conditions and for
large size problems. It should thus be useful to both practitioners and
researchers.
Abstract: The amplitude response of infrared (IR) sensors
depends on the reflectance properties of the target. Therefore, in
order to use IR sensor for measuring distances accurately, prior
knowledge of the surface must be known. This paper describes the
Phong Illumination Model for determining the properties of a surface
and subsequently calculating the distance to the surface. The angular
position of the IR sensor is computed as normal to the surface for
simplifying the calculation. Ultrasonic (US) sensor can provide the
initial information on distance to obtain the parameters for this
method. In addition, the experimental results obtained by using
LabView are discussed. More care should be taken when placing the
objects from the sensors during acquiring data since the small change
in angle could show very different distance than the actual one.
Since stereo camera vision systems do not perform well under some
environmental conditions such as plain wall, glass surfaces, or poor
lighting conditions, the IR and US sensors can be used additionally to
improve the overall vision systems of mobile robots.
Abstract: In this paper, an image adaptive, invisible digital
watermarking algorithm with Orthogonal Polynomials based
Transformation (OPT) is proposed, for copyright protection of digital
images. The proposed algorithm utilizes a visual model to determine
the watermarking strength necessary to invisibly embed the
watermark in the mid frequency AC coefficients of the cover image,
chosen with a secret key. The visual model is designed to generate a
Just Noticeable Distortion mask (JND) by analyzing the low level
image characteristics such as textures, edges and luminance of the
cover image in the orthogonal polynomials based transformation
domain. Since the secret key is required for both embedding and
extraction of watermark, it is not possible for an unauthorized user to
extract the embedded watermark. The proposed scheme is robust to
common image processing distortions like filtering, JPEG
compression and additive noise. Experimental results show that the
quality of OPT domain watermarked images is better than its DCT
counterpart.
Abstract: The focus of this research is in the area of the soviet period and the mission of the Russian Orthodox Church in Kazakhstan in the XIX century. There was close connection of national customs and traditions with religious practices, outlooks and attitudes. In particular, such an approach has alleged estimation by Kazakh historians of the process of Christianization of the local population. Some of them are inclined to consider the small number of Christening Kazakhs as evidence that the Russian Orthodox Church didn’t achieve its mission. The number of historians who think that the church didn’t achieve its mission has thousand over the last centuries, however our calculations of the number of Kazakhs who became Orthodox Christian is much more than other historians think. Such Christians can be divided into 3 groups: Some remained Christian until their deaths, others had two faiths and the third hid their true religions, having returned to their former belief. Therefore, to define the exact amount of Christening Kazakhs represented a challenge. Some data does not create a clear picture of the level of Christianization, constant and accurate was not collected. The data appearing in reports of spiritual attendants and civil authorities is not always authentic. Article purpose is illumination and the analysis missionary activity of Russian Orthodox Church in Kazakhstan.
Abstract: In this paper, RSA encryption algorithm and its hardware
implementation in Xilinx-s Virtex Field Programmable Gate
Arrays (FPGA) is analyzed. The issues of scalability, flexible performance,
and silicon efficiency for the hardware acceleration of
public key crypto systems are being explored in the present work.
Using techniques based on the interleaved math for exponentiation,
the proposed RSA calculation architecture is compared to existing
FPGA-based solutions for speed, FPGA utilization, and scalability.
The paper covers the RSA encryption algorithm, interleaved multiplication,
Miller Rabin algorithm for primality test, extended Euclidean
math, basic FPGA technology, and the implementation details of
the proposed RSA calculation architecture. Performance of several
alternative hardware architectures is discussed and compared. Finally,
conclusion is drawn, highlighting the advantages of a fully flexible
& parameterized design.
Abstract: Human ability is a major source of constraint to manufacturing industries in Nigeria. This paper therefore, discusses the importance of human influences on manufacturing and consequently to industrialization and National development. In this paper, the development of manufacturing was anchored on two main factors; Infrastructural Capacity Development (ICD) and Human Capacity Development (HCD). However, a wider view was given to the HCD and the various contemporary human capacity issues militating against manufacturing in Nigeria. It went further to discuss various ways of acquiring and upgrading workers’ skills and finally, suggestions were made on how to tackle the onerous human capacity issues in manufacturing.
Abstract: This study numerically investigates the effects of Electrohydrodynamic on flow patterns and heat transfer enhancement within a cavity which is on the lower wall of channel. In this simulation, effects of using ground wire and ground plate on the flow patterns are compared. Moreover, the positions of electrode wire respecting with ground are tested in the range of angles θ = 0 - 180o. High electrical voltage exposes to air is 20 kV. Bulk mean velocity and temperature of inlet air are controlled at 0.1 m/s and 60 OC, respectively. The result shows when electric field is applied, swirling flow is appeared in the channel. In addition, swirling flow patterns in the main flow of using ground plate are widely spreader than that of using ground wire. Moreover, direction of swirling flow also affects the flow pattern and heat transfer in a cavity. These cause the using ground wire to give the maximum temperature and heat transfer higher than using ground plate. Furthermore, when the angle is at θ = 60o, high shear flow effect is obtained. This results show high strength of swirling flow and effective heat transfer enhancement.
Abstract: One approach to assess neural networks underlying the cognitive processes is to study Electroencephalography (EEG). It is relevant to detect various mental states and characterize the physiological changes that help to discriminate two situations. That is why an EEG (amplitude, synchrony) classification procedure is described, validated. The two situations are "eyes closed" and "eyes opened" in order to study the "alpha blocking response" phenomenon in the occipital area. The good classification rate between the two situations is 92.1 % (SD = 3.5%) The spatial distribution of a part of amplitude features that helps to discriminate the two situations are located in the occipital regions that permit to validate the localization method. Moreover amplitude features in frontal areas, "short distant" synchrony in frontal areas and "long distant" synchrony between frontal and occipital area also help to discriminate between the two situations. This procedure will be used for mental fatigue detection.
Abstract: Children with hemiplgic cerebral palsy often walk
with diminished reciprocal arm swing so the purpose of this study
was to describe kinematic characteristics in children with hemiplegic
cerebral palsy (CP) during the gait suphases, and find if there is a
correlation between upper(shoulder and elbow) and lower(hip, knee,
and ankle) limb joints either in involved or uninvolved.48 children
with hemiplegic cerebral palsy (18boys, 30girls) with an average age
of (5.1±0.87) years were selected randomly to evaluate joint angles
during gait by 3D motion analysis system with 6 pro reflex cameras
in a sagittal plane for both sides of the body. The results showed
increased shoulder and elbow flexion, increased hip angular
displacement, decreased knee and ankle arcs during gait cycle, also
there is correlation between shoulder and elbow to hip, knee, and
ankle joints during various subphases of gait.
Abstract: Islamic banking is one the most blossoming doctrine in
economic system of the world. The Fast growing awareness about
Islamic financial system has brought strong feeling to Muslims to
confront the western interest-based economic cycle. The Islamic
economic system is emerging as a reliable alternative to the interest
based system. This study is proposed to ascertain the motivational
factors encouraging people to go for Islamic banking in Pakistan.
These pulsing factors are determined by generation of hypothesis that
there are certain factors which are urging people to opt Islamic
banking system and to see the differences in their ranking by applying
Friedman test. These factors include: Economically derived factors
such as stability of Islamic banks in crisis, profit and loss sharing
doctrine and equity sharing etc. This study also highlights the
religiously derived factors such as interest free banking, Shariah
tenets and supervisory of Islamic Shariah board and sociopsychological
factors.
Abstract: the cursive nature of the Arabic writing makes it
difficult to accurately segment characters or even deal with the whole
word efficiently. Therefore, in this paper, a printed Arabic sub-word
recognition system is proposed. The suggested algorithm utilizes
geometrical moments as descriptors for the separated sub-words.
Three types of moments are investigated and applied to the printed
sub-word images after dividing each image into multiple parts using
windowing. Since moments are global descriptors, the windowing
mechanism allows the moments to be applied to local regions of the
sub-word. The local-global mixture of the proposed scheme increases
the discrimination power of the moments while keeping the
simplicity and ease of use of moments.
Abstract: Repairing of the cracks by fiber metal laminates
(FMLs) was first done by some aeronautical laboratories in early
1970s. In this study, experimental investigations were done on the
effect of repairing the center-cracked aluminum plates using the FML
patches. The repairing processes were conducted to characterize the
response of the repaired structures to tensile tests. The composite
patches were made of one aluminum layer and two woven glassepoxy
composite layers. Three different crack lengths in three crack
angles and different patch lay-ups were examined. It was observed
for the lengthen cracks, the effect of increasing the crack angle on
ultimate tensile load in the structure was increase. It was indicated
that the situation of metal layer in the FML patches had an important
effect on the tensile response of the tested specimens. It was found
when the aluminum layer is farther, the ultimate tensile load has the
highest amount.
Abstract: Along with the basic features of students\' culture
information, with its widely usage oriented on implementation of the
new information technologies in educational process that determines
the search for ways of pointing to the similarity of interdisciplinary
connections content, aims and objectives of the study. In this regard,
the article questions about students\' information culture, and also
presented information about the aims and objectives of the
information culture process among students. In the formation of a
professional interest in relevant information, which is an opportunity
to assist in informing the professional activities of the essence of
effective use of interactive methods and innovative technologies in
the learning process. The result of the experiment proves the
effectiveness of the information culture process of students in
training the system of higher education based on the credit
technology. The main purpose of this paper is a comprehensive
review of students\' information culture.
Abstract: Buckling-Restrained Braced Frame system(BRBFs)
are a new type of steel seismic-load-resisting system that has found
use in several countries because of its efficiency and its promise of
seismic performance far superior to that of conventional braced
frames. The system is addressed in the 2005 edition of the AISC
Seismic Provisions for Structural Steel Buildings, also a set of design
provisions has been developed by NEHRP. This report illustrates the
seismic design of buckling restrained braced frames and compares
the result of design in the application of earthquake load for ordinary
bracing systems and buckling restrained bracing systems to see the
advantage and disadvantages of this new type of seismic resisting
system in comparison with the old Ordinary Concentric Braced
Frame systems (OCBFs); they are defined by the provisions
governing their design.