Abstract: We discuss the signal detection through nonlinear
threshold systems. The detection performance is assessed by the
probability of error Per . We establish that: (1) when the signal is
complete suprathreshold, noise always degrades the signal detection
both in the single threshold system and in the parallel array of
threshold devices. (2) When the signal is a little subthreshold, noise
degrades signal detection in the single threshold system. But in the
parallel array, noise can improve signal detection, i.e., stochastic
resonance (SR) exists in the array. (3) When the signal is predominant
subthreshold, noise always can improve signal detection and SR
always exists not only in the single threshold system but also in the
parallel array. (4) Array can improve signal detection by raising the
number of threshold devices. These results extend further the
applicability of SR in signal detection.
Abstract: this paper presents a novel scheme which is capable of reducing the error rate and improves the transmission performance in the asynchronous cooperative MIMO systems. A case study of image transmission is applied to prove the efficient of scheme. The linear dispersion structure is employed to accommodate the cooperative wireless communication network in the dynamic topology of structure, as well as to achieve higher throughput than conventional space–time codes based on orthogonal designs. The LDPC encoder without girth-4 and the STBC encoder with guard intervals are respectively introduced. The experiment results show that the combined coder of LDPC-STBC with guard intervals can be the good error correcting coders and BER performance in the asynchronous cooperative communication. In the case study of image transmission, the results show that in the transmission process, the image quality which is obtained by applied combined scheme is much better than it which is not applied the scheme in the asynchronous cooperative MIMO systems.
Abstract: The aim of this study is to develop mathematical
relationships for the performance parameter brake thermal efficiency
(BTE) and emission parameter nitrogen oxides (NOx) for the various
esters of vegetable oils used as CI engine fuel. The BTE is an
important performance parameter defining the ability of engine to
utilize the energy supplied and power developed similarly it is
indication of efficiency of fuels used. The esters of cottonseed oil,
soybean oil, jatropha oil and hingan oil are prepared using
transesterification process and characterized for their physical and
main fuel properties including viscosity, density, flash point and
higher heating value using standard test methods. These esters are
tried as CI engine fuel to analyze the performance and emission
parameters in comparison to diesel. The results of the study indicate
that esters as a fuel does not differ greatly with that of diesel in
properties. The CI engine performance with esters as fuel is in line
with the diesel where as the emission parameters are reduced with the
use of esters.
The correlation developed between BTE and brake power(BP),
gross calorific value(CV), air-fuel ratio(A/F), heat carried away by
cooling water(HCW). Another equation is developed between the
NOx emission and CO, HC, smoke density (SD), exhaust gas
temperature (EGT). The equations are verified by comparing the
observed and calculated values which gives the coefficient of
correlation of 0.99 and 0.96 for the BTE and NOx equations
respectively.
Abstract: In this paper, we develop quartic nonpolynomial
spline method for the numerical solution of third order two point
boundary value problems. It is shown that the new method gives
approximations, which are better than those produced by other spline
methods. Convergence analysis of the method is discussed through
standard procedures. Two numerical examples are given to illustrate
the applicability and efficiency of the novel method.
Abstract: In this work we study the effect of several covariates X on a censored response variable T with unknown probability distribution. In this context, most of the studies in the literature can be located in two possible general classes of regression models: models that study the effect the covariates have on the hazard function; and models that study the effect the covariates have on the censored response variable. Proposals in this paper are in the second class of models and, more specifically, on least squares based model approach. Thus, using the bootstrap estimate of the bias, we try to improve the estimation of the regression parameters by reducing their bias, for small sample sizes. Simulation results presented in the paper show that, for reasonable sample sizes and censoring levels, the bias is always smaller for the new proposals.
Abstract: As the mobile Internet has become widespread in
recent years, communication based on mobile networks is increasing.
As a result, security threats have been posed with regard to the
abnormal traffic of mobile networks, but mobile security has been
handled with focus on threats posed by mobile malicious codes, and
researches on security threats to the mobile network itself have not
attracted much attention. In mobile networks, the IP address of the data
packet is a very important factor for billing purposes. If one mobile
terminal use an incorrect IP address that either does not exist or could
be assigned to another mobile terminal, billing policy will cause
problems. We monitor and analyze 3G mobile data networks traffics
for a period of time and finds some abnormal IP packets. In this paper,
we analyze the reason for abnormal IP packets on 3G Mobile Data
Networks. And we also propose an algorithm based on IP address table
that contains addresses currently in use within the mobile data network
to detect abnormal IP packets.
Abstract: As a vital activity for companies, new product
development (NPD) is also a very risky process due to the high
uncertainty degree encountered at every development stage and the
inevitable dependence on how previous steps are successfully
accomplished. Hence, there is an apparent need to evaluate new
product initiatives systematically and make accurate decisions under
uncertainty. Another major concern is the time pressure to launch a
significant number of new products to preserve and increase the
competitive power of the company. In this work, we propose an
integrated decision-making framework based on neural networks and
fuzzy logic to make appropriate decisions and accelerate the
evaluation process. We are especially interested in the two initial
stages where new product ideas are selected (go/no go decision) and
the implementation order of the corresponding projects are
determined. We show that this two-staged intelligent approach allows
practitioners to roughly and quickly separate good and bad product
ideas by making use of previous experiences, and then, analyze a
more shortened list rigorously.
Abstract: Pyritisation halos are identified in weathering crusts and unconsolidated formations at five locations within large fault structure of the Urals’ eastern slope. Electron microscopy reveals the presence of inclusions and growths on pyrite faces – normally on cubic pyrite with striations, or combinations of cubes and other forms. Following neogenesis types are established: native elements and intermetallic compounds (including gold and silver), halogenides, sulphides, sulfosalts, tellurides, sulphotellurides,
selenides, tungstates, sulphates, phosphates, carbon-based substances. Direct relationship is noted between amount and diversity of such mineral phases, and proximity to and scale of ore-grade mineralization. Gold and silver, both in native form and within tellurides, presence of lead (galena, native lead), native tungsten, and, possibly, molybdenite and sulfosalts can indicate gold-bearing formations. First find of native tungsten in the Urals is for the first time – in crystallised and druse-like form. Link is suggested between unusual mineralization and “reducing” hydrothermal fluids from deep-seated faults at later stages of Urals’ reactivation.
Abstract: Coal tar is a liquid by-product of the process of coal
gasification and carbonation. This liquid oil mixture contains various
kinds of useful compounds such as phenol, o-cresol, and p-cresol.
These compounds are widely used as raw material for insecticides,
dyes, medicines, perfumes, coloring matters, and many others.
This research needed to be done that given the optimum conditions
for the separation of phenol, o-cresol, and p-cresol from the coal tar
by solvent extraction process. The aim of the present work was to
study the effect of two kinds of aqueous were used as solvents:
methanol and acetone solutions, the effect of temperature (298, 306,
and 313K) and mixing (30, 35, and 40rpm) for the separation of
phenol, o-cresol, and p-cresol from coal tar by solvent extraction.
Results indicated that phenol, o-cresol, and p-cresol in coal tar
were selectivity extracted into the solvent phase and these
components could be separated by solvent extraction. The aqueous
solution of methanol, mass ratio of solvent to feed, Eo/Ro=1,
extraction temperature 306K and mixing 35 rpm were the most
efficient for extraction of phenol, o-cresol, and p-cresol from coal tar.
Abstract: How to simulate experimentally the air flow and heat
transfer under microgravity on the ground is important, which has not
been completely solved so far. Influence of gravity on air natural
convection results in convection heat transfer on ground difference
from that on orbit. In order to obtain air temperature and velocity
deviations of manned spacecraft during terrestrial thermal test,
dimensionless number analysis and numerical simulation analysis are
performed. The calculated temperature distribution and velocity
distribution of the horizontal test cases are compared to the vertical
cases. The results show that the influence of gravity is neglected for
facility drawer racks and more obvious for vertical cabins.
Abstract: The significant effects of the interactions between the
system boundaries and the near wall molecules in miniaturized
gaseous devices lead to the formation of the Knudsen layer in which
the Navier-Stokes-Fourier (NSF) equations fail to predict the correct
associated phenomena. In this paper, the well-known lattice
Boltzmann method (LBM) is employed to simulate the fluid flow and
heat transfer processes in rarefied gaseous micro media. Persuaded
by the problematic deficiency of the LBM in capturing the Knudsen
layer phenomena, present study tends to concentrate on the effective
molecular mean free path concept the main essence of which is to
compensate the incapability of this mesoscopic method in dealing
with the momentum and energy transport within the above mentioned
kinetic boundary layer. The results show qualitative and quantitative
accuracy comparable to the solutions of the linearized Boltzmann
equation or the DSMC data for the Knudsen numbers of O (1) .
Abstract: The “PYRAMIDS" Block Cipher is a symmetric encryption algorithm of a 64, 128, 256-bit length, that accepts a variable key length of 128, 192, 256 bits. The algorithm is an iterated cipher consisting of repeated applications of a simple round transformation with different operations and different sequence in each round. The algorithm was previously software implemented in Cµ code. In this paper, a hardware implementation of the algorithm, using Field Programmable Gate Arrays (FPGA), is presented. In this work, we discuss the algorithm, the implemented micro-architecture, and the simulation and implementation results. Moreover, we present a detailed comparison with other implemented standard algorithms. In addition, we include the floor plan as well as the circuit diagrams of the various micro-architecture modules.
Abstract: Natural gas usually includes H2S component which is
very toxic, hazardous and corrosive to environment, human being and
process equipments, respectively. Therefore, sweetening of the gas
(separation of H2S) is inevitable. To achieve this purpose, using
packed-bed columns with liquid absorbents such as MEA or DEA is
very common. Due to some problems of usual packed columns
especially high pressure drop of gas phase, a novel kind of them
called wetted-wire column (WWC) has been invented. The column
decreases the pressure drop significantly and improves the absorption
efficiency. The packings are very thin rods (like wire) and as long as
column. The column has 100 wires with a triangular arrangement and
counter current flows of gas and liquid phases. The observation
showed that at the same conditions, the absorption performance was
quite comparable to conventional packed-bed towers and a very low
pressure drop.
Abstract: The present study was conducted to observe the effect
of Plantago psyllium on blood glucose and cholesterol levels in
normal and alloxan induced diabetic rats. To investigate the effect of
Plantago psyllium 40 rats were included in this study divided into
four groups of ten rats in each group. One group A was normal,
second group B was diabetic, third group C was non diabetic and
hypercholesterolemic and fourth group D was diabetic and
hypercholesterolemic. Two groups B and D were made diabetic by
intraperitonial injection of alloxan dissolved in 1mL distilled water at
a dose of 125mg/Kg of body weight. Two groups C and D were
made hypercholesterolemic by oral administration of powder
cholesterol (1g/Kg of body weight). The blood samples from all the
rats were collected from coccygial vein on 1st day, then on 21st and
42nd day respectively. All the samples were analyzed for blood
glucose and cholesterol level by using enzymatic kits. The blood
glucose and cholesterol levels of treated groups of rats showed
significant reduction after 7 weeks of treatment with Plantago
psyllium. By statistical analysis of results it was found that Plantago
psyllium has anti-diabetic and hypocholesterolemic activity in
diabetic and hypercholesterolemic albino rats.
Abstract: Social Business Process Management (SBPM)
promises to overcome limitations of traditional BPM by allowing
flexible process design and enactment through the involvement of
users from a social community. This paper proposes a meta-model
and architecture for socially driven business process management
systems. It discusses the main facets of the architecture such as goalbased
role assignment that combines social recommendations with
user profile, and process recommendation, through a real example of
a charity organization.
Abstract: The main aim of this paper was to investigate the
existing architecture in Cyprus, and thus identify and describe the
overall architectural rationale of the built environment. In Cyprus,
where individuals live in a society that reflects postmodern
paradigms rather than modern ones, the existing built environment
has many different reflections of the structure of its society.
Abstract: In this work, we present a comparison between
different techniques of image compression. First, the image is
divided in blocks which are organized according to a certain scan.
Later, several compression techniques are applied, combined or
alone. Such techniques are: wavelets (Haar's basis), Karhunen-Loève
Transform, etc. Simulations show that the combined versions are the
best, with minor Mean Squared Error (MSE), and higher Peak Signal
to Noise Ratio (PSNR) and better image quality, even in the presence
of noise.
Abstract: The main criteria of designing in the most hydraulic
constructions essentially are based on runoff or discharge of water. Two of those important criteria are runoff and return period. Mostly,
these measures are calculated or estimated by stochastic data.
Another feature in hydrological data is their impreciseness.
Therefore, in order to deal with uncertainty and impreciseness, based
on Buckley-s estimation method, a new fuzzy method of evaluating hydrological measures are developed. The method introduces
triangular shape fuzzy numbers for different measures in which both
of the uncertainty and impreciseness concepts are considered. Besides, since another important consideration in most of the
hydrological studies is comparison of a measure during different
months or years, a new fuzzy method which is consistent with special form of proposed fuzzy numbers, is also developed. Finally, to
illustrate the methods more explicitly, the two algorithms are tested on one simple example and a real case study.
Abstract: The following study aims to outline, whether the
perceptions of entrepreneurs about their entrepreneurial activities and
the underlying meanings of their activities are universal or whether
they vary systematically across cultures. In contrast to previous
studies, the phenomenographical approach and the resulting findings
of this study provide new insights into what constitutes
entrepreneurship by drawing an inference from the perceptions of
entrepreneurs in the United States and in Germany. Culture is shown
to have an important impact on entrepreneurship, since the
underlying meanings of entrepreneurship vary significantly among
the two sample groups. Furthermore, the study sheds more light on
the culturally contingent 'why' of entrepreneurship by looking at the
internal motivations of individuals instead of exclusively focusing on
character traits or external influences of the respective economic
environments.
Abstract: Today, people are more interested in the foods
beneficial on their health. However, there are still lacks of accurate
knowledge in the field of biological properties, functional properties,
including the application of legume in foods. This study focused on
antioxidant activity of soybean (SB) and fermented soybean (FSB)
crude extracts evaluating to have more information in fortification SB
and FSB crude extracts in food products and/or dietary supplement.
SB and FSB crude extracts were prepared by infusion with water and
ethanol. The antioxidant activity of crude extracts was studied with
DPPH and ABTS assay including commercial standard. From both
DPPH and ABTS assay, the antioxidant activity of SB and FSB water
crude extract showed higher antioxidant activity than ethanol crude
extract, and FSB crude extract showed higher antioxidant activity
than SB crude extract. In DPPH assay, BHT and vitamin C showed
IC50 values at 0.241, 0.039 mg/ml, in ABTS assay. In addition,
Trolox showed IC50 at 0.058 mg/ml respectively. FSB water crude
extract showed high antioxidant activity. Finally, the functional
properties study of both water and ethanol crude extracts should be
done for beneficial in application of these extracts in food products
and dietary supplement in the near future.