Abstract: The influence of axial magnetic field (B=0.48 T) on
the variation of ionization efficiency coefficient h and secondary
electron emission coefficient g with respect to reduced electric field
E/P is studied at a new range of plane-parallel electrode spacing (0<
d< 20 cm) and different nitrogen working pressure between 0.5-20
Pa. The axial magnetic field is produced from an inductive copper
coil of radius 5.6 cm. The experimental data of breakdown voltage is
adopted to estimate the mean Paschen curves at different working
features. The secondary electron emission coefficient is calculated
from the mean Paschen curve and used to determine the minimum
breakdown voltage. A reduction of discharge voltage of about 25% is
investigated by the applied of axial magnetic field. At high interelectrode
spacing, the effect of axial magnetic field becomes more
significant for the obtained values of h but it was less for the values
of g.
Abstract: In Algeria, liberalization reforms undertaken since the 1990s have resulted in negative effects on the development and management of irrigation schemes, as well as on the conditions of farmers. Reforms have been undertaken to improve the performance of irrigation schemes, such as the national plan of agricultural development (PNDA) in 2000 and the water pricing policy of 2005. However, after implementation of these policies, questions have arisen with regard to irrigation performance and its suitability for agricultural development. Hence, the aim of this paper is to provide insight into the profitability of irrigation during the transition period under current irrigation agricultural policies in Algeria. By using the method of farm crop budget analysis in the East Mitidja irrigation scheme, the returns from using surface water resources based on farm typology were found to vary among crops and farmers- groups within the scheme. Irrigation under the current situation is profitable for all farmers, including both those who benefit from subsidies and those who do not. However, the returns to water were found to be very sensitive to crop price fluctuations, particularly for non-subsidized groups and less so for those whose farming is based on orchards. Moreover, the socio-economic environment of the farmers contributed to less significant impacts of the PNDA policy. In fact, the limiting factor is not only the water, but also the lack of land ownership title. Market access constraints led to less agricultural investment and therefore to low intensification and low water productivity. It is financially feasible to recover the annual O&M costs in the irrigation scheme. By comparing the irrigation water price, returns to water, and O&M costs of water delivery, it is clear that irrigation can be profitable in the future. However, water productivity must be improved by enhancing farmers- income through farming investment, improving assets access, and the allocation of activities and crops which bring high returns to water; this could allow the farmers to pay more for water and allow cost recovery for water systems.
Abstract: In this paper, we start by first characterizing the most
important and distinguishing features of wavelet-based watermarking
schemes. We studied the overwhelming amount of algorithms
proposed in the literature. Application scenario, copyright protection
is considered and building on the experience that was gained,
implemented two distinguishing watermarking schemes. Detailed
comparison and obtained results are presented and discussed. We
concluded that Joo-s [1] technique is more robust for standard noise
attacks than Dote-s [2] technique.
Abstract: carbonylation of methanol in homogenous phase is
one of the major routesfor production of acetic acid. Amongst group
VIII metal catalysts used in this process iridium has displayed the
best capabilities. To investigate effect of operating parameters like:
temperature, pressure, methyl iodide, methyl acetate, iridium,
ruthenium, and water concentrations on the reaction rate,
experimental design for this system based upon central composite
design (CCD) was utilized. Statistical rate equation developed by this
method contained individual, interactions and curvature effects of
parameters on the reaction rate. The model with p-value less than
0.0001 and R2 values greater than 0.9; confirmeda satisfactory fitness
of the experimental and theoretical studies. In other words, the
developed model and experimental data obtained passed all
diagnostic tests establishing this model as a statistically significant.
Abstract: This paper addresses one important aspect of
combustion system analysis, the spray evaporation and
dispersion modeling. In this study we assume an empty
cylinder which is as a simulator for a ramjet engine and the
cylinder has been studied by cold flow. Four nozzles have the
duties of injection which are located in the entrance of
cylinder. The air flow comes into the cylinder from one side
and injection operation will be done. By changing injection
velocity and entrance air flow velocity, we have studied
droplet sizing and efficient mass fraction of fuel vapor near
and at the exit area. We named the mass of fuel vapor inside
the flammability limit as the efficient mass fraction. Further,
we decreased the initial temperature of fuel droplets and we
have repeated the investigating again. To fulfill the calculation
we used a modified version of KIVA-3V.
Abstract: There are many situations where input feature vectors are incomplete and methods to tackle the problem have been studied for a long time. A commonly used procedure is to replace each missing value with an imputation. This paper presents a method to perform categorical missing data imputation from numerical and categorical variables. The imputations are based on Simpson-s fuzzy min-max neural networks where the input variables for learning and classification are just numerical. The proposed method extends the input to categorical variables by introducing new fuzzy sets, a new operation and a new architecture. The procedure is tested and compared with others using opinion poll data.
Abstract: Academic research information service is a must for surveying previous studies in research and development process. OntoFrame is an academic research information service under Semantic Web framework different from simple keyword-based services such as CiteSeer and Google Scholar. The first purpose of this study is for revealing user behavior in their surveys, the objects of using academic research information services, and their needs. The second is for applying lessons learned from the results to OntoFrame.
Abstract: Stable nonzero populations without random deaths
caused by the Verhulst factor (Verhulst-free) are a rarity. Majority
either grow without bounds or die of excessive harmful mutations.
To delay the accumulation of bad genes or diseases, a new
environmental parameter Γ is introduced in the simulation. Current
results demonstrate that stability may be achieved by setting Γ = 0.1.
These steady states approach a maximum size that scales inversely
with reproduction age.
Abstract: Hydrothermally synthesized high silica borosilicates
with the MFI structure was subjected to several characterization
techniques. The effect of boron on the structure and acidity of
HZSM-5 catalyst were studied by XRD, SEM, N2 adsorption, solid
state NMR, NH3-TPD. It was confirmed that boron had entered the
framework in the boron samples. The results also revealed that strong
acidity was weakened and weak acidity was strengthened by the
boron added zeolite framework compared with parent catalyst. The
catalytic performance was carried out in a fixed bed at 460°C for
methanol to propylene (MTP) reaction. The results of MTP reaction
showed a great increment of the propylene selectivity and excellent
stability for the B-HZSM-5. The catalyst exhibited about 81%
selectivity to C2
= - C4
= olefins with 40% selectivity of propylene as
major component at near 100% methanol conversion, and the stable
performance in the studied period was 100h.
Abstract: A series of tests on cold-formed steel (CFS) wall plate system subjected to uplift force at the mid span of the wall plate is presented. The aim of the study was to study the behaviour and identify the modes of failure of CFS wall plate system. Two parameters were considered in these studies: 1) different dimension of U-bracket at the supports and 2) different sizes of lipped C-channel. The lipped C-channels used were C07508, C07512 and C10012. The dimensions of the leg of U-bracket were 50x35 mm and 50x60 mm respectively, where 25 mm clearance was provided to the connections for specimens with clearance. Results show that specimens with and without clearance experienced the same mode of failure. Failure began with the yielding of the connectors followed by distortional buckling of the wall plate. However, when C075 sections were used as wall plate, the system behaved differently. There was a large deformation in the wall plate and failure began in the distortional buckling of the wall plate followed by bearing of the connecting plates at the supports (U-bracket). The ultimate strength of the system also decreased dramatically when C075 sections were used.
Abstract: This study examines the impact of working capital
management on firms- performance and market value of the firms in
Nigeria. A sample of fifty four non-financial quoted firms in Nigeria
listed on the Nigeria Stock Exchange was used for this study. Data
were collected from annual reports of the sampled firms for the
period 1995-2009. This result shows there is a significant negative
relationship between cash conversion cycle and market valuation
and firm-s performance. It also shows that debt ratio is positively
related to market valuation and negatively related firm-s
performance. The findings confirm that there is a significant
relationship between Market valuation, profitability and working
capital component in line with previous studies. This mean that
Nigeria firms should ensure adequate management of working
capital especially cash conversion cycle components of account
receivables, account payables and inventories, as efficiency working
capital management is expected to contribute positively to the firms-
market value.
Abstract: Direct search methods are evolutionary algorithms used to solve optimization problems. (DS) methods do not require any information about the gradient of the objective function at hand while searching for an optimum solution. One of such methods is Pattern Search (PS) algorithm. This paper presents a new approach based on a constrained pattern search algorithm to solve a security constrained power system economic dispatch problem (SCED). Operation of power systems demands a high degree of security to keep the system satisfactorily operating when subjected to disturbances, while and at the same time it is required to pay attention to the economic aspects. Pattern recognition technique is used first to assess dynamic security. Linear classifiers that determine the stability of electric power system are presented and added to other system stability and operational constraints. The problem is formulated as a constrained optimization problem in a way that insures a secure-economic system operation. Pattern search method is then applied to solve the constrained optimization formulation. In particular, the method is tested using one system. Simulation results of the proposed approach are compared with those reported in literature. The outcome is very encouraging and proves that pattern search (PS) is very applicable for solving security constrained power system economic dispatch problem (SCED).
Abstract: In this paper, we present a novel statistical approach to
corpus-based speech synthesis. Classically, phonetic information is
defined and considered as acoustic reference to be respected. In this
way, many studies were elaborated for acoustical unit classification.
This type of classification allows separating units according to their
symbolic characteristics. Indeed, target cost and concatenation cost
were classically defined for unit selection.
In Corpus-Based Speech Synthesis System, when using large text
corpora, cost functions were limited to a juxtaposition of symbolic
criteria and the acoustic information of units is not exploited in the
definition of the target cost.
In this manuscript, we token in our consideration the unit phonetic
information corresponding to acoustic information. This would be realized
by defining a probabilistic linguistic Bi-grams model basically
used for unit selection. The selected units would be extracted from
the English TIMIT corpora.
Abstract: This research investigates the use of digital technology
namely interactive multimedia in effective art education provided by
museum. Several multimedia experience examples created for art
education are study case subjected to assistance audiences- learning
within the context of existing theory in the field of interactive
multimedia.
Abstract: A numerical method is developed for simulating
the motion of particles with arbitrary shapes in an effectively
infinite or bounded viscous flow. The particle translational and
angular motions are numerically investigated using a fluid-structure
interaction (FSI) method based on the Arbitrary-Lagrangian-Eulerian
(ALE) approach and the dynamic mesh method (smoothing and
remeshing) in FLUENT ( ANSYS Inc., USA). Also, the effects of
arbitrary shapes on the dynamics are studied using the FSI method
which could be applied to the motions and deformations of a single
blood cell and multiple blood cells, and the primary thrombogenesis
caused by platelet aggregation. It is expected that, combined with a
sophisticated large-scale computational technique, the simulation
method will be useful for understanding the overall properties of blood
flow from blood cellular level (microscopic) to the resulting
rheological properties of blood as a mass (macroscopic).
Abstract: In the present paper, active control system is used in
different heights of the building and the most effective part was
studied where the active control system is applied. The mathematical
model of the building is established in MATLAB and in order to
active control the system FLC method was used. Three different
locations of the building are chosen to apply active control system,
namely at the lowest story, the middle height of the building, and at
the highest point of the building with TMD system. The equation of
motion was written for high rise building and it was solved by statespace
method. Also passive control was used with Tuned Mass
Damper (TMD) at the top floor of the building to show the robustness
of FLC method when compared with passive control system.
Abstract: Saudi Arabia in recent years has seen drastic increase
in traffic related crashes. With population of over 29 million, Saudi
Arabia is considered as a fast growing and emerging economy. The
rapid population increase and economic growth has resulted in rapid
expansion of transportation infrastructure, which has led to increase
in road crashes. Saudi Ministry of Interior reported more than 7,000
people killed and 68,000 injured in 2011 ranking Saudi Arabia to be
one of the worst worldwide in traffic safety. The traffic safety issues
in the country also result in distress to road users and cause and
economic loss exceeding 3.7 billion Euros annually. Keeping this in
view, the researchers in Saudi Arabia are investigating ways to
improve traffic safety conditions in the country. This paper presents a
multilevel approach to collect traffic safety related data required to do
traffic safety studies in the region. Two highway corridors including
King Fahd Highway 39 kilometre and Gulf Cooperation Council
Highway 42 kilometre long connecting the cities of Dammam and
Khobar were selected as a study area. Traffic data collected included
traffic counts, crash data, travel time data, and speed data. The
collected data was analysed using geographic information system to
evaluate any correlation. Further research is needed to investigate the
effectiveness of traffic safety related data when collected in a
concerted effort.
Abstract: Dedicated Short Range Communication (DSRC) is a
key enabling technology for the next generation of
communication-based safety applications. One of the important
problems for DSRC deployment is maintaining high performance
under heavy channel load. Many studies focus on congestion control
mechanisms for simulating hundreds of physical radios deployed on
vehicles. The U.S. department of transportation-s (DOT) Intelligent
Transportation Systems (ITS) division has a plan to chosen prototype
on-board devices capable of transmitting basic “Here I am" safety
messages to other vehicles. The devices will be used in an IntelliDrive
safety pilot deployment of up to 3,000 vehicles. It is hard to log the
information of 3,000 vehicles. In this paper we present the designs and
issues related to the DSRC Radio Testbed under heavy channel load.
The details not only include the architecture of DSRC Radio Testbed,
but also describe how the Radio Interfere System is used to help for
emulating the congestion radio environment.
Abstract: In the paper, the relative performances on spectral
classification of short exon and intron sequences of the human and
eleven model organisms is studied. In the simulations, all
combinations of sixteen one-sequence numerical representations, four
threshold values, and four window lengths are considered. Sequences
of 150-base length are chosen and for each organism, a total of
16,000 sequences are used for training and testing. Results indicate
that an appropriate combination of one-sequence numerical
representation, threshold value, and window length is essential for
arriving at top spectral classification results. For fixed-length
sequences, the precisions on exon and intron classification obtained
for different organisms are not the same because of their genomic
differences. In general, precision increases as sequence length
increases.
Abstract: Recently, in some places, optical-fibre access
networks have been used with GPON technology belonging to
organizations (in most cases public bodies) that act as neutral
operators. These operators simultaneously provide network services
to various telecommunications operators that offer integrated voice,
data and television services. This situation creates new problems
related to quality of service, since the interests of the users are
intermingled with the interests of the operators. In this paper, we
analyse this problem and consider solutions that make it possible to
provide guaranteed quality of service for voice over IP, data services
and interactive digital television.