Abstract: In this note, we demonstrate explicit LU
factorizations of Toeplitz matrices for some small sizes. Furthermore,
we obtain the inverse of referred Toeplitz matrices by appling the
above-mentioned results.
Abstract: In this paper, we propose a fuzzy aggregate
production planning (APP) model for blending problem in a brass
factory which is the problem of computing optimal amounts of raw
materials for the total production of several types of brass in a
period. The model has deterministic and imprecise parameters
which follows triangular possibility distributions. The brass casting
APP model can not always be solved by using common approaches
used in the literature. Therefore a mathematical model is presented
for solving this problem. In the proposed model, the Lai and
Hwang-s fuzzy ranking concept is relaxed by using one constraint
instead of three constraints. An application of the brass casting
APP model in a brass factory shows that the proposed model
successfully solves the multi-blend problem in casting process and
determines the optimal raw material purchasing policies.
Abstract: The conjugate gradient optimization algorithm is combined with the modified back propagation algorithm to yield a computationally efficient algorithm for training multilayer perceptron (MLP) networks (CGFR/AG). The computational efficiency is enhanced by adaptively modifying initial search direction as described in the following steps: (1) Modification on standard back propagation algorithm by introducing a gain variation term in the activation function, (2) Calculation of the gradient descent of error with respect to the weights and gains values and (3) the determination of a new search direction by using information calculated in step (2). The performance of the proposed method is demonstrated by comparing accuracy and computation time with the conjugate gradient algorithm used in MATLAB neural network toolbox. The results show that the computational efficiency of the proposed method was better than the standard conjugate gradient algorithm.
Abstract: A numerical solution of the initial boundary value
problem of the suspended string vibrating equation with the
particular nonlinear damping term based on the finite difference
scheme is presented in this paper. The investigation of how the
second and third power terms of the nonlinear term affect the
vibration characteristic. We compare the vibration amplitude as a
result of the third power nonlinear damping with the second power
obtained from previous report provided that the same initial shape
and initial velocities are assumed. The comparison results show that
the vibration amplitude is inversely proportional to the coefficient of
the damping term for the third power nonlinear damping case, while
the vibration amplitude is proportional to the coefficient of the
damping term in the second power nonlinear damping case.
Abstract: An alternative approach to the use of Discrete Fourier
Transform (DFT) for Magnetic Resonance Imaging (MRI) reconstruction
is the use of parametric modeling technique. This method
is suitable for problems in which the image can be modeled by
explicit known source functions with a few adjustable parameters.
Despite the success reported in the use of modeling technique as an
alternative MRI reconstruction technique, two important problems
constitutes challenges to the applicability of this method, these are
estimation of Model order and model coefficient determination. In
this paper, five of the suggested method of evaluating the model
order have been evaluated, these are: The Final Prediction Error
(FPE), Akaike Information Criterion (AIC), Residual Variance (RV),
Minimum Description Length (MDL) and Hannan and Quinn (HNQ)
criterion. These criteria were evaluated on MRI data sets based on the
method of Transient Error Reconstruction Algorithm (TERA). The
result for each criterion is compared to result obtained by the use of a
fixed order technique and three measures of similarity were evaluated.
Result obtained shows that the use of MDL gives the highest measure
of similarity to that use by a fixed order technique.
Abstract: Electromagnetic flowmeters with DC excitation are used for a wide range of fluid measurement tasks, but are rarely found in dosing applications with short measurement cycles due to the achievable accuracy. This paper will identify a number of factors that influence the accuracy of this sensor type when used for short-term measurements. Based on these results a new signal-processing algorithm will be described that overcomes the identified problems to some extend. This new method allows principally a higher accuracy of electromagnetic flowmeters with DC excitation than traditional methods.
Abstract: The paper is included within the framework of a
complex research program, which was initiated from the hypothesis
arguing on the existence of a correlation between pineal indolic and
peptide hormones and the somatic development rhythm, including
thus the epithalamium-epiphysis complex involvement. At birds,
pineal gland contains a circadian oscillator, playing a main role in the
temporal organization of the cerebral functions. The secretion of
pineal indolic hormones is characterized by a high endogenous
rhythmic alternation, modulated by the light/darkness (L/D)
succession and by temperature as well. The research has been carried
out using 100 chicken broilers - “Ross" commercial hybrid,
randomly allocated in two experimental batches: Lc batch, reared
under a 12L/12D lighting schedule and Lexp batch, which was photic
pinealectomised through continuous exposition to light (150 lux, 24
hours, 56 days). Chemical and physical features of the meat issued
from breast fillet and thighs muscles have been studied, determining
the dry matter, proteins, fat, collagen, salt content and pH value, as
well. Besides the variations of meat chemical composition in relation
with lighting schedule, other parameters have been studied: live
weight dynamics, feed intake and somatic development degree. The
achieved results became significant since chickens have 7 days of
age, some variations of the studied parameters being registered,
revealing that the pineal gland physiologic activity, in relation with
the lighting schedule, could be interpreted through the monitoring of
the somatic development technological parameters, usually studied
within the chicken broilers rearing aviculture practice.
Abstract: In this paper we present an energy efficient match-line
(ML) sensing scheme for high-speed ternary content-addressable
memory (TCAM). The proposed scheme isolates the sensing unit of
the sense amplifier from the large and variable ML capacitance. It
employs feedback in the sense amplifier to successfully detect a
match while keeping the ML voltage swing low. This reduced voltage
swing results in large energy saving. Simulation performed using
130nm 1.2V CMOS logic shows at least 30% total energy saving in
our scheme compared to popular current race (CR) scheme for
similar search speed. In terms of speed, dynamic energy, peak power
consumption and transistor count our scheme also shows better
performance than mismatch-dependant (MD) power allocation
technique which also employs feedback in the sense amplifier.
Additionally, the implementation of our scheme is simpler than CR
or MD scheme because of absence of analog control voltage and
programmable delay circuit as have been used in those schemes.
Abstract: An HPLC-UV analytical method was developed to
determine ethylenediaminetetraacetic acid (EDTA) in dairy
wastewater and surface water. The optimizing separation was achieved
by reversed–phase ion-pair liquid chromatography on a C18 column
using methanol as mobile phase solvent, tetrabutylammonium bromide
as the ion-pair reagent in pH 3.3 formate buffer solution at a flow rate
of 0.9 mL min-1 with a UV detector at 265 nm. No interference of Ca,
Mg or NO3
- was detected. Method performance was evaluated in terms
of linearity, repeatability and reproducibility. The method detection
limit was 5 μg L-1. The contents of EDTA in dairy effluents were 72 ~
261 μg L-1 at a large dairy site. A change of EDTA concentration was
observed downstream of the dairy effluent discharge, but this was well
under the predicted no effect concentration for aquatic ecosystem.
Abstract: Network on a chip (NoC) has been proposed as a viable solution to counter the inefficiency of buses in the current VLSI on-chip interconnects. However, as the silicon chip accommodates more transistors, the probability of transient faults is increasing, making fault tolerance a key concern in scaling chips. In packet based communication on a chip, transient failures can corrupt the data packet and hence, undermine the accuracy of data communication. In this paper, we present a comparative analysis of transient fault tolerant techniques including end-to-end, node-by-node, and stochastic communication based on flooding principle.
Abstract: The use of a Geographic Information System (GIS) in
roadway lighting to show the state of street-lighting and nighttime
accident is demonstrated. Geographical maps were generated
showing colored streets based on how much of the street's length is
illuminated. The night to daytime accidents ratio at intersections
were found along with the state of lighting at those intersections.
The result is a method to show the state of street-lighting at roads and
intersections and a quick guide for decision makers to implement
strategies for better street-lighting to reduce night time traffic
accidents in a particular district.
Abstract: Aiming the application of localized hyperthermia, a
magnetic induction system with new approaches is proposed. The techniques in this system for improving the effectiveness of localized hyperthermia are that using magnetic circuit and the multiple-coil array instead of a giant coil for generating magnetic field. Specially, amorphous metal is adopted as the material of magnetic circuit. Detail
design parameters of hardware are well described. Simulation tool is
employed for this work and experiment result is reported as well.
Abstract: In this paper, half bridge DC-DC converters with
transformer isolation presented in the literature are analyzed for highcurrent
and low-voltage applications under the same operation
conditions, and compared in terms of losses and efficiency. The
conventional and improved half-bridge DC-DC converters are
simulated, and current and voltage waveforms are obtained for input
voltage Vdc=500V, output current IO=450A, output voltage VO=38V
and switching frequency fS=20kHz. IGBTs are used as power
semiconductor switches. The power losses of the semiconductor
devices are calculated from current and voltage waveforms. From
simulation results, it is seen that the capacitor switched half bridge
converter has the best efficiency value, and can be preferred at high
power and high frequency applications.
Abstract: A modified Saleh-Valenzuela channel model has been
adapted for Ultra Wideband (UWB) system. The suggested realistic
channel is assessed by its distribution of fading amplitude and time of
arrivals. Furthermore, the propagation characteristic has been distinct
into four channel models, namely CM 1 to 4. Each are differentiate in
terms of cluster arrival rates, rays arrival rate within each cluster and
its respective constant decay rates. This paper described the
multiband OFDM system performance simulates under these
multipath conditions. Simulation work described in this paper is
based on WiMedia ECMA-368 standard, which has been deployed
for practical implementation of low cost and low power UWB
devices.
Abstract: We depend upon explanation in order to “make sense"
out of our world. And, making sense is all the more important when
dealing with change. But, what happens if our explanations are
wrong? This question is examined with respect to two types of
explanatory model. Models based on labels and categories we shall
refer to as “representations." More complex models involving
stories, multiple algorithms, rules of thumb, questions, ambiguity we
shall refer to as “compressions." Both compressions and
representations are reductions. But representations are far more
reductive than compressions. Representations can be treated as a set
of defined meanings – coherence with regard to a representation is
the degree of fidelity between the item in question and the definition
of the representation, of the label. By contrast, compressions contain
enough degrees of freedom and ambiguity to allow us to make
internal predictions so that we may determine our potential actions in
the possibility space. Compressions are explanatory via mechanism.
Representations are explanatory via category. Managers are often
confusing their evocation of a representation (category inclusion) as
the creation of a context of compression (description of mechanism).
When this type of explanatory error occurs, more errors follow. In
the drive for efficiency such substitutions are all too often proclaimed
– at the manager-s peril..
Abstract: This paper proposes a fast tree join scheme to provide
seamless multicast handover in the mobile networks based on the Fast
Mobile IPv6 (FMIPv6). In the existing FMIPv6-based multicast
handover scheme, the bi-directional tunnelling or the remote
subscription is employed with the packet forwarding from the previous
access router (AR) to the new AR. In general, the remote subscription
approach is preferred to the bi-directional tunnelling one, since in the
remote subscription scheme we can exploit an optimized multicast
path from a multicast source to many mobile receivers. However, in
the remote subscription scheme, if the tree joining operation takes a
long time, the amount of data packets to be forwarded and buffered for
multicast handover will increase, and thus the corresponding buffer
may overflow, which results in severe packet losses. In order to reduce
these costs associated with packet forwarding and buffering, this paper
proposes the fast join to multicast tree, in which the new AR will join
the multicast tree as fast as possible, so that the new multicast data
packets can also arrive at the new AR, by which the packet forwarding
and buffering costs can be reduced. From numerical analysis, it is
shown that the proposed scheme can give better performance than the
existing FMIPv6-based multicast handover schemes in terms of the
multicast packet delivery costs.
Abstract: A new automatic system for the recognition and re¬construction of resealed and/or rotated partially occluded objects is presented. The objects to be recognized are described by 2D views and each view is occluded by several half-planes. The whole object views and their visible parts (linear cuts) are then stored in a database. To establish if a region R of an input image represents an object possibly occluded, the system generates a set of linear cuts of R and compare them with the elements in the database. Each linear cut of R is associated to the most similar database linear cut. R is recognized as an instance of the object 0 if the majority of the linear cuts of R are associated to a linear cut of views of 0. In the case of recognition, the system reconstructs the occluded part of R and determines the scale factor and the orientation in the image plane of the recognized object view. The system has been tested on two different datasets of objects, showing good performance both in terms of recognition and reconstruction accuracy.
Abstract: The effect of flooding can be a serious problem for
wheat farmers, even at dry land condition. Amount of flooding
damage depends on duration flooding, developmental stage, wheat
type and variety. Therefore as a factorial experiment in randomized
complete design based on winter bread wheat cultivars (Pishtaz,
Marvdasht, Shiraz, Zarin, Shahriar, C-81-4, Sardari, Agosta seed,
FGS and Azar2) at stages (Non- flooding stress, flooding at tillering
and stem elongation stages for 15 days) carried out in Faculty of
Agriculture, Razi University, Kermanshah, Iran. During flooding,
soil environment of plant roots were water saturated. Analysis of
variance showed that flooding had a significant effect on the number
of grains per spike, grain weight per spike and a grain weight. Hence
flooding reduces the number of grain per spike between 27.1 to 42.5
percent, grain weight per spike between 34.7 to 54.4 percent and
single grain weight between 12.1 to 15.1 percent. Effects of flooding
at the tillering stage reduced higher than stem elongation stage on
studied traits. The result also showed that flooding at tillering stage
delayed spikelet primordial and floret. Between wheat cultivars was
significant for traits, but were different reactions. "Shiraz", "Zarin"
and "Shahriar" had the most no. grain per spike, but "Zarin" and
"Sardari" had the most grain weight per spike and single grain
weight, respectively. Also, interaction between start of flooding and
cultivar was significant.
Abstract: A new Markovianity approach is introduced in this
paper. This approach reduces the response time of classic Markov
Random Fields approach. First, one region is determinated by a
clustering technique. Then, this region is excluded from the study.
The remaining pixel form the study zone and they are selected for a
Markovianity segmentation task. With Selective Markovianity
approach, segmentation process is faster than classic one.
Abstract: Although the level crossing concept has been the subject of intensive investigation over the last few years, certain problems of great interest remain unsolved. One of these concern is distribution of threshold levels. This paper presents a new threshold level allocation schemes for level crossing based on nonuniform sampling. Intuitively, it is more reasonable if the information rich regions of the signal are sampled finer and those with sparse information are sampled coarser. To achieve this objective, we propose non-linear quantization functions which dynamically assign the number of quantization levels depending on the importance of the given amplitude range. Two new approaches to determine the importance of the given amplitude segment are presented. The proposed methods are based on exponential and logarithmic functions. Various aspects of proposed techniques are discussed and experimentally validated. Its efficacy is investigated by comparison with uniform sampling.