Abstract: Electroencephalogram (EEG) recordings are often
contaminated with ocular and muscle artifacts. In this paper, the
canonical correlation analysis (CCA) is used as blind source
separation (BSS) technique (BSS-CCA) to decompose the artifact
contaminated EEG into component signals. We combine the BSSCCA
technique with wavelet filtering approach for minimizing both
ocular and muscle artifacts simultaneously, and refer the proposed
method as wavelet enhanced BSS-CCA. In this approach, after
careful visual inspection, the muscle artifact components are
discarded and ocular artifact components are subjected to wavelet
filtering to retain high frequency cerebral information, and then clean
EEG is reconstructed. The performance of the proposed wavelet
enhanced BSS-CCA method is tested on real EEG recordings
contaminated with ocular and muscle artifacts, for which power
spectral density is used as a quantitative measure. Our results suggest
that the proposed hybrid approach minimizes ocular and muscle
artifacts effectively, minimally affecting underlying cerebral activity
in EEG recordings.
Abstract: The distance protection mainly the impedance relay which is considered as the main protection for transmission lines can be subjected to impedance measurement error which is, mainly, due to the fault resistance and to the power fluctuation. Thus, the impedance relay may not operate for a short circuit at the far end of the protected line (case of the under reach) or operates for a fault beyond its protected zone (case of overreach). In this paper, an approach to fault detection by a distance protection, which distinguishes between the faulty conditions and the effect of overload operation mode, has been developed. This approach is based on the symmetrical components; mainly the negative sequence, and it is taking into account both the effect of fault resistance and the overload situation which both have an effect upon the reliability of the protection in terms of dependability for the former and security for the latter.
Abstract: The results show that the bridge equipped with seismic isolation bearing system shows a high amount of energy dissipation. The purpose of the present study is to analyze the overall performance of continuous curved highway viaducts with different bearing supports, with an emphasis on the effectiveness of seismic isolation based on lead rubber bearing and hedge reaction force bearing system consisted of friction sliding bearing and rubber bearing. The bridge seismic performance has been evaluated on six different cases with six bearing models. The effects of the different arrangement of bearing on the deck superstructure displacements, the seismic damage at the bottom of the piers, movement track at the pier-s top and the total and strain energies absorbed by the structure are evaluated. In conclusion, the results provide sufficient evidence of the effectiveness on the use of seismic isolation on steel curved highway bridges.
Abstract: Presently and in line with the United Nations (EPA),
human thinking system has shifted towards clean fuels so as to
maintain a cleaner environment and to save our planet earth.
One of the most successful studies in order to achieve new
energies includes the use of animal wastes and their organic residues,
and the result of these researches has been represented in the form of
very simple and cheap methods called biogas technology. Biogas
technology has developed a lot in the recent decades; its reason is the
high cost of fossil fuels and the greater attention of countries to the
environmental pollutions due to the consumption of this kind of
fuels.
IRAN is ready for the optimized application of renewable
energies, having much enriched resources of this kind of energies; so
a special place could be considered for it when making programs.
The purpose of biogas technology is the recovery of energy and
finally the protection of the environment, which is much appropriate
for the third world farmers with respect to their technical abilities and
economic potentials. Studies show that the production and
consumption of biogas is appropriate and economic in IRAN,
because of the high amount of waste in the agriculture sector, the
significant amount of animal and human excrement production, the
great volume of garbage produced and the most important the
specific social, climatic and agricultural conditions in IRAN, in order
to proceed towards the reduction of pollution due to the use of fossil
fuels.
Abstract: Multiplication algorithms have considerable effect on
processors performance. A new high-speed, low-power
multiplication algorithm has been presented using modified Dadda
tree structure. Three important modifications have been implemented
in inner product generation step, inner product reduction step and
final addition step. Optimized algorithms have to be used into basic
computation components, such as multiplication algorithms. In this
paper, we proposed a new algorithm to reduce power, delay, and
transistor count of a multiplication algorithm implemented using low
power modified counter. This work presents a novel design for
Dadda multiplication algorithms. The proposed multiplication
algorithm includes structured parts, which have important effect on
inner product reduction tree. In this paper, a 1.3V, 64-bit carry hybrid
adder is presented for fast, low voltage applications. The new 64-bit
adder uses a new circuit to implement the proposed carry hybrid
adder. The new adder using 80 nm CMOS technology has been
implemented on 700 MHz clock frequency. The proposed
multiplication algorithm has achieved 14 percent improvement in
transistor count, 13 percent reduction in delay and 12 percent
modification in power consumption in compared with conventional
designs.
Abstract: Despite of the preponderant role played by cement among the construction materials, it is today considered as a material destructing the environment due to the large quantities of carbon dioxide exhausted during its manufacture. Besides, global warming is now recognized worldwide as the new threat to the humankind against which advanced countries are investigating measures to reduce the current amount of exhausted gases to the half by 2050. Accordingly, efforts to reduce green gases are exerted in all industrial fields. Especially, the cement industry strives to reduce the consumption of cement through the development of alkali-activated geopolymer mortars using industrial byproducts like bottom ash. This study intends to gather basic data on the flowability and strength development characteristics of alkali-activated geopolymer mortar by examining its FT-IT features with respect to the effects and strength of the alkali-activator in order to develop bottom ash-based alkali-activated geopolymer mortar. The results show that the 35:65 mass ratio of sodium hydroxide to sodium silicate is appropriate and that a molarity of 9M for sodium hydroxide is advantageous. The ratio of the alkali-activators to bottom ash is seen to have poor effect on the strength. Moreover, the FT-IR analysis reveals that larger improvement of the strength shifts the peak from 1060 cm–1 (T-O, T=Si or Al) toward shorter wavenumber.
Abstract: Vertical Double Gate (DG) Metal Oxide Semiconductor Field Effect Transistor (MOSFET) is believed to suppress various short channel effect problems. The gate to channel coupling in vertical DG-MOSFET are doubled, thus resulting in higher current density. By having two gates, both gates are able to control the channel from both sides and possess better electrostatic control over the channel. In order to ensure that the transistor possess a superb turn-off characteristic, the subs-threshold swing (SS) must be kept at minimum value (60-90mV/dec). By utilizing SILVACO TCAD software, an n-channel vertical DG-MOSFET was successfully designed while keeping the sub-threshold swing (SS) value as minimum as possible. From the observation made, the value of sub-threshold swing (SS) was able to be varied by adjusting the height of the silicon pillar. The minimum value of sub-threshold swing (SS) was found to be 64.7mV/dec with threshold voltage (VTH) of 0.895V. The ideal height of the vertical DG-MOSFET pillar was found to be at 0.265 µm.
Abstract: In this study acoustic emission (AE) signals obtained during deformation and fracture of two types of ferrite-martensite dual phase steels (DPS) specimens have been analyzed in frequency domain. For this reason two low carbon steels with various amounts of carbon were chosen, and intercritically heat treated. In the introduced method, identifying the mechanisms of failure in the various phases of DPS is done. For this aim, AE monitoring has been used during tensile test of several DPS with various volume fraction of the martensite (VM) and attempted to relate the AE signals and failure mechanisms in these steels. Different signals, which referred to 2-3 micro-mechanisms of failure due to amount of carbon and also VM have been seen. By Fast Fourier Transformation (FFT) of signals in distinct locations, an excellent relationship between peak frequencies in these areas and micro-mechanisms of failure were seen. The results were verified by microscopic observations (SEM).
Abstract: In this paper, we propose a selective mutation method
for improving the performances of genetic algorithms. In selective
mutation, individuals are first ranked and then additionally mutated
one bit in a part of their strings which is selected corresponding to
their ranks. This selective mutation helps genetic algorithms to fast
approach the global optimum and to quickly escape local optima.
This results in increasing the performances of genetic algorithms.
We measured the effects of selective mutation with four function
optimization problems. It was found from extensive experiments that
the selective mutation can significantly enhance the performances of
genetic algorithms.
Abstract: Nosocomial (i.e., hospital-acquired) infections
(NI) is a major cause of morbidity and mortality in hospitals. NI
rate is higher in intensive care units (ICU) than in the general
ward due to patients with severe symptoms, poor immunity,
and accepted many invasive therapies. Contact behaviors
between health caregivers and patients is one of the infect
factors. It is difficult to obtain complete contact records by
traditional method of retrospective analysis of medical records.
This paper establishes a contact history inferential model
(CHIM) intended to extend the use of Proximity Sensing of
rapid frequency identification (RFID) technology to
transferring all proximity events between health caregivers and
patients into clinical events (close-in events, contact events and
invasive events).The results of the study indicated that the
CHIM can infer proximity care activities into close-in events
and contact events.
The infection control team could redesign and build optimal
workflow in the ICU according to the patient-specific contact
history which provided by our automatic tracing system.
Abstract: A conventional image posterization method
occasionally fails to preserve the shape and color of objects due to the
uneffective color reduction. This paper proposes a new image
posterizartion method by using modified color quantization for
preserving the shape and color of objects and color contrast
enhancement for improving lightness contrast and saturation.
Experiment results show that our proposed method can provide
visually more satisfactory posterization result than that of the
conventional method.
Abstract: In a bid to improve turbine entry temperature for maximizing the thermal efficiency of the HP stage gas turbine blade, an attempt is made in this paper to compare the performance of helicoidal ducted blade cooling with turbulator of different geometric proportion. It is found from analysis that there is significant improvement in cooling characteristics for turbine blade with turbulator geometry having larger e/D ratio. Also it is found from analysis, performance is vastly improved for greater thickness of turbulator geometry.
Abstract: The influence of physical (external added weight) and
neurophysiological (fatigue) factors on static and dynamic balance in
sport related activities was typified statically by the Romberg test
(one foot flat, eyes open) and dynamically by jumping and hopping
in both horizontal and vertical directions. Twenty healthy males were
participated in this study. In Static condition, added weight increased
body-s inertia and therefore decreased body sway in AP direction
though not significantly. Dynamically, added weight significantly
increased body sway in both ML and AP directions, indicating
instability, and the use of the counter rotating segments mechanism to
maintain balance was demonstrated. Fatigue on the other hand
significantly increased body sway during static balance as a
neurophysiological adaptation primarily to the inverted pendulum
mechanism. Dynamically, fatigue significantly increased body sway
in both ML and AP directions again indicating instability but with a
greater use of counter rotating segments mechanism. Differential
adaptations for each of the two balance mechanisms (inverted
pendulum and counter rotating segments) were found between one
foot flat and two feet flat dynamic conditions, as participants relied
more heavily on the first in the one foot flat conditions and relied
more on the second in the two feet flat conditions.
Abstract: Previous researches found that conventional WBL is effective for meaningful learner, because rote learner learn by repeating without thinking or trying to understand. It is impossible to have full benefit from conventional WBL. Understanding of rote learner-s intention and what influences it becomes important. Poorly designed user interface will discourage rote learner-s cultivation and intention to use WBL. Thus, user interface design is an important factor especially when WBL is used as comprehensive replacement of conventional teaching. This research proposes the influencing factors that can enhance learner-s intention to use the system. The enhanced TAM is used for evaluating the proposed factors. The research result points out that factors influencing rote learner-s intention are Perceived Usefulness of Homepage Content Structure, Perceived User Friendly Interface, Perceived Hedonic Component, and Perceived (homepage) Visual Attractiveness.
Abstract: This paper presents a speed sensorless direct torque
control scheme using space vector modulation (DTC-SVM) for
permanent magnet synchronous motor (PMSM) drive based a Model
Reference Adaptive System (MRAS) algorithm and stator resistance
estimator. The MRAS is utilized to estimate speed and stator
resistance and compensate the effects of parameter variation on stator
resistance, which makes flux and torque estimation more accurate
and insensitive to parameter variation. In other hand the use of SVM
method reduces the torque ripple while achieving a good dynamic
response. Simulation results are presented and show the effectiveness
of the proposed method.
Abstract: The fabrication of porous NiTi shape memory alloys (SMAs) from elemental powder compacts was conducted by selfpropagating high temperature synthesis (SHS). Effects of the preheating temperature and the chamber pressure on the combustion characteristics as well as the final morphology and the composition of products were studied. The samples with porosity between 56.4 and 59.0% under preheating temperature in the range of 200-300°C and Ar-gas chamber pressure of 138 and 201 kPa were obtained. The pore structures were found to be dissimilar only in the samples processed with different preheating temperature. The major phase in the porous product is NiTi with small amounts of secondary phases, NiTi2 and Ni4Ti3. The preheating temperature and the chamber pressure have very little effect on the phase constituent. While the combustion temperature of the sample was notably increased by increasing the preheating temperature, they were slightly changed by varying the chamber pressure.
Abstract: Study of the vibration cylindrical shells made of
a functionally gradient material (FGM) composed of stainless
steel and nickel is important. Material properties are graded in
the thickness direction of the shell according to volume
fraction power law distribution. The objective is to study the
natural frequencies, the influence of constituent volume
fractions and the effects of boundary conditions on the natural
frequencies of the FG cylindrical shell. The study is carried
out using third order shear deformation shell theory. The
governing equations of motion of FG cylindrical shells are
derived based on shear deformation theory. Results are
presented on the frequency characteristics, influence of
constituent volume fractions and the effects of clampedclamped
boundary conditions.
Abstract: In this paper an extensive verification of the extraction
method (published earlier) that consistently accounts for self-heating
and Early effect to accurately extract both base and thermal resistance
of bipolar junction transistors is presented. The method verification is
demonstrated on advanced RF SiGe HBTs were the extracted results
for the thermal resistance are compared with those from another
published method that ignores the effect of Early effect on internal
base-emitter voltage and the extracted results of the base resistance
are compared with those determined from noise measurements. A
self-consistency of our method in the extracted base resistance and
thermal resistance using compact model simulation results is also
carried out in order to study the level of accuracy of the method.
Abstract: There are many expand of Wi-Fi zones provided
mobile careers and usage of wireless access point at home as increase
of usage of wireless internet caused by the use of smart phone. This
paper shows wireless local area network status, security threats of
WLAN and functionality of major wireless access point in Korea. We
propose security countermeasures concerned with life cycle of access
point from manufacturing to installation, using and finally disposal.
There needed to releasing with configured secure at access point.
Because, it is most cost effective resolution than stage of installation or
other life cycle of access point.
Abstract: In this paper, based on the work in [1], we further give
a general model for acquiring knowledge, which first focuses on the
research of how and when things involved in problems are made
then describes the goals, the energy and the time to give an optimum
model to decide how many related things are supposed to be involved
in. Finally, we acquire knowledge from this model in which there are
the attributes, actions and connections of the things involved at the
time when they are born and the time in their life. This model not
only improves AI theories, but also surely brings the effectiveness
and accuracy for AI system because systems are given more
knowledge when reasoning or computing is used to bring about
results.