Abstract: In recent years, scanning probe atomic force
microscopy SPM AFM has gained acceptance over a wide spectrum
of research and science applications. Most fields focuses on physical,
chemical, biological while less attention is devoted to manufacturing
and machining aspects. The purpose of the current study is to assess
the possible implementation of the SPM AFM features and its
NanoScope software in general machining applications with special
attention to the tribological aspects of cutting tool. The surface
morphology of coated and uncoated as-received carbide inserts is
examined, analyzed, and characterized through the determination of
the appropriate scanning setting, the suitable data type imaging
techniques and the most representative data analysis parameters
using the MultiMode SPM AFM in contact mode. The NanoScope
operating software is used to capture realtime three data types
images: “Height", “Deflection" and “Friction". Three scan sizes are
independently performed: 2, 6, and 12 μm with a 2.5 μm vertical
range (Z). Offline mode analysis includes the determination of three
functional topographical parameters: surface “Roughness", power
spectral density “PSD" and “Section". The 12 μm scan size in
association with “Height" imaging is found efficient to capture every
tiny features and tribological aspects of the examined surface. Also,
“Friction" analysis is found to produce a comprehensive explanation
about the lateral characteristics of the scanned surface. Configuration
of many surface defects and drawbacks has been precisely detected
and analyzed.
Abstract: Car accident is one of the major causes of death in many countries. Many researchers have attempted to design and develop techniques to increase car safety in the past recent years. In spite of all the efforts, it is still challenging to design a system adaptive to the driver rather than the automotive characteristics. In this paper, the adaptive car safety system is explained which attempts to find a balance.
Abstract: For stable bipedal gait generation on the level floor,
efficient restoring of mechanical energy lost by heel collision at
the ground is necessary. Parametric excitation principle is one of
the solutions. We dealt with the robot-s total center of mass as
an inverted pendulum to consider the total dynamics of the robot.
Parametrically excited walking requires the use of continuous target
trajectory that is close to discontinuous optimal trajectory. In this
paper, we proposed the new target trajectory based on a position
in the walking direction. We surveyed relations between walking
performance and the parameters that form the target trajectory via
numerical simulations. As a result, it was found that our target
trajectory has the similar characteristics of a parametrically excited
inverted pendulum.
Abstract: The effect of wheat flour extraction rates on flour
composition, farinographic characteristics and the quality of
sourdough naans was investigated. The results indicated that by
increasing the extraction rate, the amount of protein, fiber, fat and
ash increased, whereas moisture content decreased. Farinographic
characteristic like water absorption and dough development time
increased with an increase in flour extraction rate but the dough
stabilities and tolerance indices were reduced with an increase in
flour extraction rates. Titratable acidity for both sourdough and
sourdough naans also increased along with flour extraction rate. The
study showed that overall quality of sourdough naans were affected
by both flour extraction rate and starter culture used. Sensory
analysis of sourdough naans revealed that desirable extraction rate
for sourdough naan was 76%.
Abstract: In this study, the effect of nanofluids on the pool film
boiling was experimentally investigated at saturated condition under
atmospheric pressure. For this purpose, four different water-based
nanofluids (Al2O3, SiO2, TiO2 and CuO) with 0.1% particle volume
fraction were prepared. To investigate the boiling heat transfer, a
cylindrical rod with high temperature was used. The rod heated up to
high temperatures was immersed into nanofluids. The center
temperature of rod during the cooling process was recorded by using
a K-type thermocouple. The quenching curves showed that the pool
boiling heat transfer was strongly dependent on the nanoparticle
materials. During the repetitive quenching tests, the cooling time
decreased and thus, the film boiling vanished. Consequently, the
primary reason of this was the change of the surface characteristics
due to the nanoparticles deposition on the rod-s surface.
Abstract: The power consumption of an Optical Packet Switch
equipped with SOA technology based Spanke switching fabric is
evaluated. Sophisticated analytical models are introduced to evaluate
the power consumption versus the offered traffic, the main
switch parameters, and the used device characteristics. The impact
of Amplifier Spontaneous Emission (ASE) noise generated by a
transmission system on the power consumption is investigated. As
a matter of example for 32×32 switches supporting 64 wavelengths
and offered traffic equal to 0,8, the average energy consumption per
bit is 5, 07 · 10-2 nJ/bit and increases if ASE noise introduced by
the transmission systems is increased.
Abstract: This paper presents a methodology for operational and
economic characteristics based evaluation and selection of a power
plant using Graph theoretic approach. A universal evaluation index
on the basis of Operational and economics characteristics of a plant is
proposed which evaluates and ranks the various types of power plants.
The index thus obtained from the pool of operational characteristics
of the power plant attributes Digraph. The Digraph is developed
considering Operational and economics attributes of the power plants
and their relative importance for their smooth operation, installation
and commissioning and prioritizing their selection. The sensitivity
analysis of the attributes towards the objective has also been carried
out in order to study the impact of attributes over the desired outcome
i.e. the universal operational-economics index of the power plant.
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: Herein, the organic semiconductor methyl orange
(MO), is investigated for the first time for its electronic applications.
For this purpose, Al/MO/n-Si heterojunction is fabricated through
economical cheap and simple “drop casting” technique. The currentvoltage
(I-V) measurements of the device are made at room
temperature under dark conditions. The I-V characteristics of
Al/MO/n-Si junction exhibits asymmetrical and rectifying behavior
that confirms the formation of diode. The diode parameters such as
rectification ratio (RR), turn on voltage (Vturn on), reverse saturation
current (I0), ideality factor (n), barrier height ( b
f ), series resistance
(Rs) and shunt resistance (Rsh) are determined from I-V curves using
Schottky equations. These values of these parameters are also
extracted and verified by applying Cheung’s functions. The
conduction mechanisms are explained from the forward bias I-V
characteristics using the power law.
Abstract: The present investigation aimed to study the
histomorphometric characterizations of the thyroid gland of the duck.
Five adult male and five adult female ducks were used in the
experiment. Results showed that the overall histological structure of
the thyroid gland of the duck were similar to those of the other
vertebrae. The gland consisted of roughly spherical randomly
distributed micro and macrofollicles with very little interstitial tissue
between them. Each follicle is lined by a single layer of epithelial
cells enclosing a cavity, the follicular cavity, which is filled with
colloid. Ultrastructural findings showed that the apical surface of the
follicular cells bears a variable number of short, irregularly
distributed microvilli which are apparently more numerous on the
columnar cells than on the lower, relatively inactive cells.
Mitochondria and rough endoplasmic reticulum occupy the
subnuclear region of the follicular cell, whereas the Golgi complex,
free ribosomes and colloid droplets were found in the apical
cytoplasm. At light or electron microscopic levels, there was no sex
difference in histomorphometric characteristics of the thyroid
glands.ls.
Abstract: The study will search the level of existence of the
sweethearting in Saudi Arabia's Supermarkets in Riyadh.
Sweethearting occurs when frontline workers give unauthorized free
or uncounted goods and services to customer-s conspirators. The
store managers and /or security managers were asked about the
sweethearting that occurs in the supermarkets. The characteristics of
sweethearting in Riyadh stores were investigated. Two independent
variables were related to the report of sweethearting. These
independent variables are: The effect of store environment on
sweethearting and the security techniques and loss prevention
electronics techniques used. This study expected to shed the light
about the level of sweethearting in Saudi Arabia and the factors
behind it. This study will serve as an exploratory study for such
phenomenon in Saudi Arabia as well as both descriptive for the
characteristics of sweethearting and explanatory study to link
between the environmental and security systems factors to
sweethearting.
Abstract: UWB is a very attractive technology for many
applications. It provides many advantages such as fine resolution and high power efficiency. Our interest in the current study is the use of
UWB radar technique in microwave medical imaging systems, especially for early breast cancer detection. The Federal Communications Commission FCC allowed frequency bandwidth of
3.1 to 10.6 GHz for this purpose. In this paper we suggest an UWB Bowtie slot antenna with enhanced bandwidth. Effects of varying the geometry of the antenna
on its performance and bandwidth are studied. The proposed antenna
is simulated in CST Microwave Studio. Details of antenna design and
simulation results such as return loss and radiation patterns are discussed in this paper. The final antenna structure exhibits good
UWB characteristics and has surpassed the bandwidth requirements.
Abstract: Array signal processing involves signal enumeration and source localization. Array signal processing is centered on the ability to fuse temporal and spatial information captured via sampling signals emitted from a number of sources at the sensors of an array in order to carry out a specific estimation task: source characteristics (mainly localization of the sources) and/or array characteristics (mainly array geometry) estimation. Array signal processing is a part of signal processing that uses sensors organized in patterns or arrays, to detect signals and to determine information about them. Beamforming is a general signal processing technique used to control the directionality of the reception or transmission of a signal. Using Beamforming we can direct the majority of signal energy we receive from a group of array. Multiple signal classification (MUSIC) is a highly popular eigenstructure-based estimation method of direction of arrival (DOA) with high resolution. This Paper enumerates the effect of missing sensors in DOA estimation. The accuracy of the MUSIC-based DOA estimation is degraded significantly both by the effects of the missing sensors among the receiving array elements and the unequal channel gain and phase errors of the receiver.
Abstract: EPA (Ethernet for Plant Automation) resolves the nondeterministic problem of standard Ethernet and accomplishes real-time communication by means of micro-segment topology and deterministic scheduling mechanism. This paper studies the real-time performance of EPA periodic data transmission from theoretical and experimental perspective. By analyzing information transmission characteristics and EPA deterministic scheduling mechanism, 5 indicators including delivery time, time synchronization accuracy, data-sending time offset accuracy, utilization percentage of configured timeslice and non-RTE bandwidth that can be used to specify the real-time performance of EPA periodic data transmission are presented and investigated. On this basis, the test principles and test methods of the indicators are respectively studied and some formulas for real-time performance of EPA system are derived. Furthermore, an experiment platform is developed to test the indicators of EPA periodic data transmission in a micro-segment. According to the analysis and the experiment, the methods to improve the real-time performance of EPA periodic data transmission including optimizing network structure, studying self-adaptive adjustment method of timeslice and providing data-sending time offset accuracy for configuration are proposed.
Abstract: One of the main consequences of the ubiquitous usage of Internet as a means to conduct business has been the progressive internationalization of contracts created to support such transactions. As electronic commerce becomes International commerce, the reality is that commercial disputes will occur creating such questions as: "In which country do I bring proceedings?" and "Which law is to be applied to solve disputes?" The decentralized and global structure of the Internet and its decentralized operation have given e-commerce a transnational element that affects two questions essential to any transaction: applicable law and jurisdiction in the event of dispute. The sharing of applicable law and jurisdiction among States in respect of international transactions traditionally has been based on the use of contact factors generally of a territorial nature (the place where real estate is located, customary residence, principal establishment, place of shipping goods). The characteristics of the Internet as a new space sometimes make it difficult to apply these rules, and may make them inoperative or lead to results that are surprising or totally foreign to the contracting parties and other elements and circumstances of the case.
Abstract: Chatter vibration has been a troublesome problem for a
machine tool toward the high precision and high speed machining.
Essentially, the machining performance is determined by the dynamic
characteristics of the machine tool structure and dynamics of cutting
process. Therefore the dynamic vibration behavior of spindle tool
system greatly determines the performance of machine tool. The
purpose of this study is to investigate the influences of the machine
frame structure on the dynamic frequency of spindle tool unit through
finite element modeling approach. To this end, a realistic finite
element model of the vertical milling system was created by
incorporated the spindle-bearing model into the spindle head stock of
the machine frame. Using this model, the dynamic characteristics of
the milling machines with different structural designs of spindle head
stock and identical spindle tool unit were demonstrated. The results of
the finite element modeling reveal that the spindle tool unit behaves
more compliant when the excited frequency approaches the natural
mode of the spindle tool; while the spindle tool show a higher dynamic
stiffness at lower frequency that may be initiated by the structural
mode of milling head. Under this condition, it is concluded that the
structural configuration of spindle head stock associated with the
vertical column of milling machine plays an important role in
determining the machining dynamics of the spindle unit.
Abstract: This paper focuses on PSS/E modeling of wind farms
of Doubly-fed Induction Generator (DFIG) type and their impact on
issues of power system operation. Since Wind Turbine Generators
(WTG) don-t have the same characteristics as synchronous
generators, the appropriate modeling of wind farms is essential for
transmission system operators to analyze the best options of
transmission grid reinforcements as well as to evaluate the wind
power impact on reliability and security of supply. With the high
excepted penetration of wind power into the power system a
simultaneous loss of Wind Farm generation will put at risk power
system security and reliability. Therefore, the main wind grid code
requirements concern the fault ride through capability and frequency
operation range of wind turbines. In case of grid faults wind turbines
have to supply a definite reactive power depending on the
instantaneous voltage and to return quickly to normal operation.
Abstract: Background noise is particularly damaging to speech
intelligibility for people with hearing loss especially for sensorineural
loss patients. Several investigations on speech intelligibility have
demonstrated sensorineural loss patients need 5-15 dB higher SNR
than the normal hearing subjects. This paper describes Discrete
Cosine Transform Power Normalized Least Mean Square algorithm
to improve the SNR and to reduce the convergence rate of the LMS
for Sensory neural loss patients. Since it requires only real arithmetic,
it establishes the faster convergence rate as compare to time domain
LMS and also this transformation improves the eigenvalue
distribution of the input autocorrelation matrix of the LMS filter.
The DCT has good ortho-normal, separable, and energy compaction
property. Although the DCT does not separate frequencies, it is a
powerful signal decorrelator. It is a real valued function and thus
can be effectively used in real-time operation. The advantages of
DCT-LMS as compared to standard LMS algorithm are shown via
SNR and eigenvalue ratio computations. . Exploiting the symmetry
of the basis functions, the DCT transform matrix [AN] can be
factored into a series of ±1 butterflies and rotation angles. This
factorization results in one of the fastest DCT implementation. There
are different ways to obtain factorizations. This work uses the fast
factored DCT algorithm developed by Chen and company. The
computer simulations results show superior convergence
characteristics of the proposed algorithm by improving the SNR at
least 10 dB for input SNR less than and equal to 0 dB, faster
convergence speed and better time and frequency characteristics.
Abstract: Different methods containing biometric algorithms are
presented for the representation of eigenfaces detection including
face recognition, are identification and verification. Our theme of this
research is to manage the critical processing stages (accuracy, speed,
security and monitoring) of face activities with the flexibility of
searching and edit the secure authorized database. In this paper we
implement different techniques such as eigenfaces vector reduction
by using texture and shape vector phenomenon for complexity
removal, while density matching score with Face Boundary Fixation
(FBF) extracted the most likelihood characteristics in this media
processing contents. We examine the development and performance
efficiency of the database by applying our creative algorithms in both
recognition and detection phenomenon. Our results show the
performance accuracy and security gain with better achievement than
a number of previous approaches in all the above processes in an
encouraging mode.
Abstract: This paper evaluates the association between
economic environment in the districts of Madrid (Spain) and physical
inactivity, using income per capita as indicator of economic
environment. The analysis included 6,601 individuals aged 16 to 74
years. The measure of association estimated was the prevalence odds
ratio for physical inactivity by income per capita. After adjusting for
sex, age, and individual socioeconomic characteristics, people living
in the districts with the lowest per capita income had an odds ratio for
physical inactivity 1.58 times higher (95% confidence interval 1.35 to
1.85) than those living in districts with the highest per capita income.
Additional adjustment for the availability of sports facilities in each
district did not decrease the magnitude of the association. These
findings show that the widely believed assumption that the
availability of sports and recreational facilities, as a possible
explanation for the relation between economic environment and
physical inactivity, cannot be considered a universal observation.