Abstract: This paper proposes two novel schemes for pilot-aided
integer frequency offset (IFO) estimation in orthogonal frequency
division multiplexing (OFDM)-based digital video broadcastingterrestrial
(DVB-T) systems. The conventional scheme proposed for
estimating the IFO uses only partial information of combinations
that pilots can provide, which stems from a rigorous assumption
that the channel responses of pilots used for estimating the IFO
change very rapidly. Thus, in this paper, we propose the novel IFO
estimation schemes exploiting all information of combinations that
pilots can provide to improve the performance of IFO estimation.
The simulation results show that the proposed schemes are highly
accurate in terms of the IFO detection probability.
Abstract: Rice husk is a lignocellulosic source that can be
converted to ethanol. Three hundreds grams of rice husk was mixed
with 1 L of 0.18 N sulfuric acid solutions then was heated in an
autoclave. The reaction was expected to be at constant temperature
(isothermal), but before that temperature was achieved, reaction has
occurred. The first liquid sample was taken at temperature of 140 0C
and repeated every 5 minute interval. So the data obtained are in the
regions of non-isothermal and isothermal. It was observed that the
degradation has significant effects on the ethanol production. The
kinetic constants can be expressed by Arrhenius equation with the
frequency factors for hydrolysis and sugar degradation of 1.58 x 105
1/min and 2.29 x 108 L/mole/min, respectively, while the activation
energies are 64,350 J/mole and 76,571 J/mole. The highest ethanol
concentration from fermentation is 1.13% v/v, attained at 220 0C.
Abstract: Since 2004, we have been developing an in-situ storage image sensor (ISIS) that captures more than 100 consecutive images at a frame rate of 10 Mfps with ultra-high sensitivity as well as the video camera for use with this ISIS. Currently, basic research is continuing in an attempt to increase the frame rate up to 100 Mfps and above. In order to suppress electro-magnetic noise at such high frequency, a digital-noiseless imaging transfer scheme has been developed utilizing solely sinusoidal driving voltages. This paper presents highly efficient-yet-accurate expressions to estimate attenuation as well as phase delay of driving voltages through RC networks of an ultra-high-speed image sensor. Elmore metric for a fundamental RC chain is employed as the first-order approximation. By application of dimensional analysis to SPICE data, we found a simple expression that significantly improves the accuracy of the approximation. Similarly, another simple closed-form model to estimate phase delay through fundamental RC networks is also obtained. Estimation error of both expressions is much less than previous works, only less 2% for most of the cases . The framework of this analysis can be extended to address similar issues of other VLSI structures.
Abstract: This paper proposes a vertical beamforming concept
to a cellular network employing Fractional Frequency Reuse
technique including with cell sectorization. Two different beams are
utilized in cell-center and cell-edge, separately. The proposed concept
is validated through computer simulation in term of SINR and
channel capacity. Also, comparison when utilizing horizontal and
vertical beam formation is in focus. The obtained results indicate
that the proposed concept can improve the performance of the
cellular networks comparing with the one using horizontal
beamforming.
Abstract: This paper describes a method of signal process applied
on an end effects of Hilbert-Huang transform (HHT) to provide an
improvement in the reality of spectrum. The method is based on
back-propagation network (BPN). To improve the effect, the end
extension of the original signal is obtained by back-propagation
network. A full waveform including origin and its extension is
decomposed by using empirical mode decomposition (EMD) to obtain
intrinsic mode functions (IMFs) of the waveform. Then, the Hilbert
transform (HT) is applied to the IMFs to obtain the Hilbert spectrum of
the waveform. As a result, the method is superiority of the processing
of end effect of HHT to obtain the real frequency spectrum of signals.
Abstract: In the present study, we aimed to design the
intrauterine and extrauterine exposure to 1800 MHz GSM-like RF
radiation and investigate its possible bio-effects on infant female
rabbits. Totally thirty-six New Zealand White female rabbits, onemonth
old, were randomly divided into four groups which are
composed of 9 rabbits; i. Group I [Intrauterine (IU) exposure(-);
Extrauterine (EU) exposure (-)], Group II [IU exposure (-); EU
exposure (+)], Group III [IU exposure(+);EU exposure(-)], Group IV
[IU exposure (+);EU exposure(+)]. The master regulatory enzymes
activities of pentose phosphate pathway (glucose-6-phosphate
dehydrogenase, G-6PD; 6-phosphogluconate dehydrogenase, 6-
PGDH) and glutathione-dependent metabolism (glutathione
peroxidase, GSH-Px; glutathione reductase, GR; glutathione Stransferase,
GST, thioredoxin reductase, TRx) were analyzed in liver
tissues of young female rabbits. Decreased G-6PD, 6-PGD, GSH-Px,
GR activities were found in Group III compared to Group I (p
Abstract: This paper discusses aspects of re-design of loadshedding
schemes with respect to actual developments in the Kosovo
power system. Load-shedding is a type of emergency control that is
designed to ensure system stability by reducing power system load to
match the power generation supply. This paper presents a new
adaptive load-shedding scheme that provides emergency protection
against excess frequency decline, in cases when the Kosovo power
system might be disconnected from the regional transmission
network. The proposed load-shedding scheme uses the local
frequency rate information to adapt the load-shedding pattern to suit
the size and location of the occurring disturbance. The proposed
scheme is tested in a software simulation on a large scale PSS/E
model which represents nine power system areas of Southeast Europe
including the Kosovo power system.
Abstract: A fundamental model consisting of charged particles
moving in free space exposed to alternating and direct current (ACDC)
electromagnetic fields is analyzed. Effects of charged particles
initial position and initial velocity to cyclotron resonance frequency
are observed. Strong effects are observed revealing that effects of
electric and magnetic fields on a charged particle in free space
varies with the initial conditions. This indicates the frequency where
maximum displacement occur can be changed. At this frequency
the amplitude of oscillation of the particle displacement becomes
unbounded.
Abstract: Real world Speaker Identification (SI) application
differs from ideal or laboratory conditions causing perturbations that
leads to a mismatch between the training and testing environment
and degrade the performance drastically. Many strategies have been
adopted to cope with acoustical degradation; wavelet based Bayesian
marginal model is one of them. But Bayesian marginal models
cannot model the inter-scale statistical dependencies of different
wavelet scales. Simple nonlinear estimators for wavelet based
denoising assume that the wavelet coefficients in different scales are
independent in nature. However wavelet coefficients have significant
inter-scale dependency. This paper enhances this inter-scale
dependency property by a Circularly Symmetric Probability Density
Function (CS-PDF) related to the family of Spherically Invariant
Random Processes (SIRPs) in Log Gabor Wavelet (LGW) domain
and corresponding joint shrinkage estimator is derived by Maximum
a Posteriori (MAP) estimator. A framework is proposed based on
these to denoise speech signal for automatic speaker identification
problems. The robustness of the proposed framework is tested for
Text Independent Speaker Identification application on 100 speakers
of POLYCOST and 100 speakers of YOHO speech database in three
different noise environments. Experimental results show that the
proposed estimator yields a higher improvement in identification
accuracy compared to other estimators on popular Gaussian Mixture
Model (GMM) based speaker model and Mel-Frequency Cepstral
Coefficient (MFCC) features.
Abstract: The purpose of this research was to study five vital
factors related to employees’ job performance. A total of 250
respondents were sampled from employees who worked at a public
warehouse organization, Bangkok, Thailand. Samples were divided
into two groups according to their work experience. The average
working experience was about 9 years for group one and 28 years for
group two. A questionnaire was utilized as a tool to collect data.
Statistics utilized in this research included frequency, percentage,
mean, standard deviation, t-test analysis, one way ANOVA, and
Pearson Product-moment correlation coefficient. Data were analyzed
by using Statistical Package for the Social Sciences. The findings
disclosed that the majority of respondents were female between 23-
31 years old, single, and hold an undergraduate degree. The average
income of respondents was less than 30,900 baht. The findings also
revealed that the factors of organization chart awareness, job process
and technology, internal environment, employee loyalty, and policy
and management were ranked as medium level. The hypotheses
testing revealed that difference in gender, age, and position had
differences in terms of the awareness of organization chart, job
process and technology, internal environment, employee loyalty, and
policy and management in the same direction with low level.
Abstract: Relevant agricultural information disseminator
(extension agent) ratio of 1:3500 farm families which become a
menace to agricultural production capacity in developing countries
necessitate this study. Out of 4 zones in the state, 24 extension agents
in each zone, 4 extension agents using cell phones and 120 farmers
using cell phone and 120 other farmers not using cell phone were
purposively selected to give 240 farmers that participated in the
research. Data were collected using interview guide and analysized
using frequency, percentage and t-test.. Frequency of contact with
agricultural information centers revealed that cell phone user farmers
had greater means score of X 41.43 contact as against the low mean
X19.32 contact recorded by farmers receiving agricultural
information from extension agents not using cell phone and their
production was statistically significant at P < 0.05. Usage of cell
phone increase extension agent contact and increase farmers-
production capacity.
Abstract: A multiphase harmonic load flow algorithm is developed based on backward/forward sweep to examine the effects of various factors on the neutral to earth voltage (NEV), including unsymmetrical system configuration, load unbalance and harmonic injection. The proposed algorithm composes fundamental frequency and harmonic frequencies power flows. The algorithm and the associated models are tested on IEEE 13 bus system. The magnitude of NEV is investigated under various conditions of the number of grounding rods per feeder lengths, the grounding rods resistance and the grounding resistance of the in feeding source. Additionally, the harmonic injection of nonlinear loads has been considered and its influences on NEV under different conditions are shown.
Abstract: The paper shows some ability to manage two-phase
flows arising from the use of unsteady effects. In one case, we
consider the condition of fragmentation of the interface between the
two components leads to the intensification of mixing. The problem
is solved when the temporal and linear scale are small for the
appearance of the developed mixing layer. Showing that exist such
conditions for unsteady flow velocity at the surface of the channel,
which will lead to the creation and fragmentation of vortices at Re
numbers of order unity. Also showing that the Re is not a criterion of
similarity for this type of flows, but we can introduce a criterion that
depends on both the Re, and the frequency splitting of the vortices. It
turned out that feature of this situation is that streamlines behave
stable, and if we analyze the behavior of the interface between the
components it satisfies all the properties of unstable flows. The other
problem we consider the behavior of solid impurities in the extensive
system of channels. Simulated unsteady periodic flow modeled
breaths. Consider the behavior of the particles along the trajectories.
It is shown that, depending on the mass and diameter of the particles,
they can be collected in a caustic on the channel walls, stop in a
certain place or fly back. Of interest is the distribution of particle
velocity in frequency. It turned out that by choosing a behavior of the
velocity field of the carrier gas can affect the trajectory of individual
particles including force them to fly back.
Abstract: Digital watermarking is one of the techniques for
copyright protection. In this paper, a normalization-based robust
image watermarking scheme which encompasses singular value
decomposition (SVD) and discrete cosine transform (DCT)
techniques is proposed. For the proposed scheme, the host image is
first normalized to a standard form and divided into non-overlapping
image blocks. SVD is applied to each block. By concatenating the
first singular values (SV) of adjacent blocks of the normalized image,
a SV block is obtained. DCT is then carried out on the SV blocks to
produce SVD-DCT blocks. A watermark bit is embedded in the highfrequency
band of a SVD-DCT block by imposing a particular
relationship between two pseudo-randomly selected DCT
coefficients. An adaptive frequency mask is used to adjust local
watermark embedding strength. Watermark extraction involves
mainly the inverse process. The watermark extracting method is blind
and efficient. Experimental results show that the quality degradation
of watermarked image caused by the embedded watermark is visually
transparent. Results also show that the proposed scheme is robust
against various image processing operations and geometric attacks.
Abstract: Complaints today have the ability to retain
customer loyalty using state of the art systems and strategies
in customer relationship management to analyze and respond
to a plethora of customer perception. The Majority of
companies are not aware of the beneficiary utilization of
customer complaints for the sake of quality improvements.
Also, some companies have problems determining how
resolution of complaints can be profitable. In this study, we
will define the problems and ascertain the importance of
customer management system on the companies. Furthermore,
we will determine the impact of such a system on efficiency,
confidence, profitability and customer complaints. Eventually,
we will develop methods and address the issues. In this paper,
we used an open-ended questionnaire and distributed that to
30 randomly chosen respondents which were the passengers in
an airport. We also define three hypotheses for our study and
we will validate each of them. Then using frequency, Chi-
Square and quality control method we optimized the size of
customers- negative feedback and improved the process of
customer retention.
Abstract: Recently, the RFID (Radio Frequency
Identification) technology attracts the world market attention as
essential technology for ubiquitous environment. The RFID
market has focused on transponders and reader development.
But that concern has shifted to RFID software like as
high-valued e-business applications, RFID middleware and
related development tools. However, due to the high sensitivity
of data and service transaction within the RFID network,
security consideration must be addressed. In order to guarantee
trusted e-business based on RFID technology, we propose a
security enhanced RFID middleware system. Our proposal is
compliant with EPCglobal ALE (Application Level Events),
which is standard interface for middleware and its clients. We
show how to provide strengthened security and trust by
protecting transported data between middleware and its client,
and stored data in middleware. Moreover, we achieve the
identification and service access control against illegal service
abuse. Our system enables secure RFID middleware service
and trusted e-business service.
Abstract: The problem of frequent itemset mining is considered in this paper. One new technique proposed to generate frequent patterns in large databases without time-consuming candidate generation. This technique is based on focusing on transaction instead of concentrating on itemset. This algorithm based on take intersection between one transaction and others transaction and the maximum shared items between transactions computed instead of creating itemset and computing their frequency. With applying real life transactions and some consumption is taken from real life data, the significant efficiency acquire from databases in generation association rules mining.
Abstract: As embedded and portable systems were emerged power consumption of circuits had been major challenge. On the other hand latency as determines frequency of circuits is also vital task. Therefore, trade off between both of them will be desirable. Modulo 2n+1 adders are important part of the residue number system (RNS) based arithmetic units with the interesting moduli set (2n-1,2n, 2n+1). In this manuscript we have introduced novel binary representation to the design of modulo 2n+1 adder. VLSI realization of proposed architecture under 180 nm full static CMOS technology reveals its superiority in terms of area, power consumption and power-delay product (PDP) against several peer existing structures.
Abstract: The frequency dependence of the phase field
model(PFM) is studied. A simple PFM is proposed, and is tested in a
laminar boundary layer. The Blasius-s laminar boundary layer
solution on a flat plate is used for the flow pattern, and several
frequencies are imposed on the PFM, and the decay times of the
interfaces are obtained. The computations were conducted for three
cases: 1) no-flow, and 2) a half ball on the laminar boundary layer, 3) a
line of mass sources in the laminar boundary layer. The computations
show the decay time becomes shorter as the frequency goes larger, and
also show that it is sensitive to both background disturbances and
surface tension parameters. It is concluded that the proposed simple
PFM can describe the properties of decay process, and could give the
fundamentals for the decay of the interface in turbulent flows.
Abstract: We present design, fabrication, and characterization of
a small (12 mm × 12 mm × 8 mm) movable railway vehicle for sensor
carrying. The miniature railway vehicle (MRV) was mainly composed
of a vibrational structure and three legs. A railway was designed and
fabricated to power and guide the MRV. It also transmits the sensed
data from the MRV to the signal processing unit. The MRV with legs
on the railway was moving due to its high-frequency vibration. A
model was derived to describe the motion. Besides, FEM simulations
were performed to design the legs. Then, the MRV and the railway
were fabricated by precision machining. Finally, an infrared sensor
was carried and tested. The result shows that the MRV without loading
was moving along the railway and its maximum speed was 12.2 mm/s.
Moreover, the testing signal was sensed by the MRV.