Abstract: Direct conversion of methane to methanol by partial oxidation in a thermal reactor has a poor yield of about 2% which is less than the expected economical yield of about 10%. Conventional thermal catalytic reactors have been proposed to be superseded by plasma reactors as a promising approach, due to strength of the electrical energy which can break C-H bonds of methane. Among the plasma techniques, non-thermal dielectric barrier discharge (DBD) plasma chemical process is one of the most future promising technologies in synthesizing methanol. The purpose of this paper is presenting a brief review of CH4 oxidation with O2 in DBD plasma reactors based on the recent investigations. For this reason, the effect of various parameters of reactor configuration, feed ratio, applied voltage, residence time (gas flow rate), type of applied catalyst, pressure and reactor wall temperature on methane conversion and methanol selectivity are discussed.
Abstract: A number of routing algorithms based on learning
automata technique have been proposed for communication
networks. How ever, there has been little work on the effects of
variation of graph scarcity on the performance of these algorithms. In
this paper, a comprehensive study is launched to investigate the
performance of LASPA, the first learning automata based solution to
the dynamic shortest path routing, across different graph structures
with varying scarcities. The sensitivity of three main performance
parameters of the algorithm, being average number of processed
nodes, scanned edges and average time per update, to variation in
graph scarcity is reported. Simulation results indicate that the LASPA
algorithm can adapt well to the scarcity variation in graph structure
and gives much better outputs than the existing dynamic and fixed
algorithms in terms of performance criteria.
Abstract: The main aim of this paper is to investigate the exponential stability of the Euler method for a stochastic age-dependent population equations with Poisson random measures. It is proved that the Euler scheme is exponentially stable in mean square sense. An example is given for illustration.
Abstract: The problem of exponential stability and periodicity for a class of cellular neural networks (DCNNs) with time-varying delays is investigated. By dividing the network state variables into subgroups according to the characters of the neural networks, some sufficient conditions for exponential stability and periodicity are derived via the methods of variation parameters and inequality techniques. These conditions are represented by some blocks of the interconnection matrices. Compared with some previous methods, the method used in this paper does not resort to any Lyapunov function, and the results derived in this paper improve and generalize some earlier criteria established in the literature cited therein. Two examples are discussed to illustrate the main results.
Abstract: This research investigates the effects of the opening
shape and location on the structural behavior of reinforced concrete
deep beam with openings, while keeping the opening size unchanged.
The software ANSYS 12.1 is used to handle the nonlinear finite
element analysis. The ultimate strength of reinforced concrete deep
beam with opening obtained by ANSYS 12.1 shows fair agreement
with the experimental results, with a difference of no more than 20%. The present work concludes that the opening location has much more effect on the structural strength than the opening shape. It was
concluded that placing the openings near the upper corners of the
deep beam may double the strength, and the use of a rectangular
narrow opening, with the long sides in the horizontal direction, can save up to 40% of structural strength of the deep beam.
Abstract: Air quality studies were carried out in the towns of
Putrajaya, Petaling Jaya and Nilai in the Malaysian Peninsular. In this
study, the variations of Ozone (O3) concentrations over a four year
period (2008-2011) were investigated using data obtained from the
Malaysian Department of the Environment (DOE). This study aims to
identify and describe the daily and monthly variations of O3
concentrations at the monitoring sites mentioned. The SPPS program
(Statistical Package for the Social Science) was used to analyze this
data in order to obtain the variations of O3 and also to clarify the
relationship between the stations. The findings of the study revealed
that the highest concentration of O3 occurred during the midday and
afternoon (between 13:00-15:00 hrs). The comparison between
stations also showed that highest O3 concentrations were recorded in
Putrajaya. The comparisons of average and maximum concentrations
of O3 for the three stations showed that the strongest significant
correlation was recorded in the Petaling Jaya station with the value
R2= 0.667. Results from this study indicate that in the urban areas of
Peninsular Malaysia, the concentration of O3 depends on the
concentration of NOx. Furthermore, HYSPLIT back trajectories
(-72h) indicated that air-mass transport patterns can also influence the
O3 concentration in the areas studied.
Abstract: In order to investigate water deficit stress on 24 of
soybean (Glycine Max. L) cultivars and lines in temperate climate, an
experiment was conducted in Iran Seed and Plant Improvement
Institute. Stress levels were irrigation after evaporation of 50, 100,
150 mm water from pan, class A. Randomized Completely Block
Design was arranged for each stress levels. Some traits such as, node
number, plant height, pod number per area, grain number per pod,
grain number per area, 1000 grains weight, grain yield and harvest
index were measured. Results showed that water deficit stress had
significant effect on node number, plant height, pod number per area,
grain number per pod, grain number per area, 1000 grains weight and
harvest index. Also all of agronomic traits except harvest index
influenced significantly by cultivars and lines. The least and most
grain yield was belonged to Ronak X Williams and M41 x Clark
respectively.
Abstract: In this paper we ultra low-voltage and high speed CMOS domino logic. For supply voltages below 500mV the delay for a ultra low-voltage NAND2 gate is aproximately 10% of a complementary CMOS inverter. Furthermore, the delay variations due to mismatch is much less than for conventional CMOS. Differential domino gates for AND/NAND and OR/NOR operation are presented.
Abstract: In this work, study the location of interface in a stirred vessel with Rushton impeller by computational fluid dynamic was presented. To modeling rotating the impeller, sliding mesh (SM) technique was used and standard k-ε model was selected for turbulence closure. Mean tangential, radial and axial velocities and also turbulent kinetic energy (k) and turbulent dissipation rate (ε) in various points of tank was investigated. Results show sensitivity of system to location of interface and radius of 7 to 10cm for interface in the vessel with existence characteristics cause to increase the accuracy of simulation.
Abstract: This paper deals with the comparison between two proposed control strategies for a DC-DC boost converter. The first control is a classical Sliding Mode Control (SMC) and the second one is a distance based Fuzzy Sliding Mode Control (FSMC). The SMC is an analytical control approach based on the boost mathematical model. However, the FSMC is a non-conventional control approach which does not need the controlled system mathematical model. It needs only the measures of the output voltage to perform the control signal. The obtained simulation results show that the two proposed control methods are robust for the case of load resistance and the input voltage variations. However, the proposed FSMC gives a better step voltage response than the one obtained by the SMC.
Abstract: Using a methodology grounded in business process
change theory, we investigate the critical success factors that affect
ERP implementation success in United States and India.
Specifically, we examine the ERP implementation at two case study
companies, one in each country. Our findings suggest that certain
factors that affect the success of ERP implementations are not
culturally bound, whereas some critical success factors depend on the
national culture of the country in which the system is being
implemented. We believe that the understanding of these critical
success factors will deepen the understanding of ERP
implementations and will help avoid implementation mistakes,
thereby increasing the rate of success in culturally different contexts.
Implications of the findings and future research directions for both
academicians and practitioners are also discussed.
Abstract: Design and land use are closely linked to the
energy efficiency levels for an urban area. The current city
planning practice does not involve an effective land useenergy
evaluation in its 'blueprint' urban plans. The study
proposed an appraisal method that can be embedded in GIS
programs using five planning criteria as how far a planner can
give away from the planning principles (criteria) for the most
energy output s/he can obtain. The case of Balcova, a district
in the Izmir Metropolitan area, is used conformingly for
evaluating the proposed master plan and the geothermal
energy (heating only) use for the concern district.
If the land use design were proposed accordingly at-most
energy efficiency (a 30% obtained), mainly increasing the
density around the geothermal wells and also proposing more
mixed use zones, we could have 17% distortion (infidelity to
the main planning principles) from the original plan. The
proposed method can be an effective tool for planners as
simulation media, of which calculations can be made by GIS
ready tools, to evaluate efficiency levels for different plan
proposals, letting to know how much energy saving causes
how much deviation from the other planning ideals. Lower
energy uses can be possible for different land use proposals
for various policy trials.
Abstract: In this research, a part of Aghche basin in Isfahan
province with an area about 2000 hectars, was chosen to be obtain
curve number coefficient runoff and W indicator in second Cook
method By using aerial photos 1968 and 1995, the satellite data of
the IRS in 2008. Then the process of land use changes in the period
of study and its effect on the changes of curve number (CN), W
indicator and surface runoff coefficient (C) of the basin was
investigated. These results showed that on the track of these land use
changes the weight averages curve number (CN), surface runoff
coefficient (C) and W indicator of the basin were increased to 0.92,
0.02 and 0.78 unit in the first period of study and 1.18, 0.03, 0.99
Unit in the second period of study respectively.
Abstract: Wind turbines with double output induction
generators can operate at variable speed permitting conversion
efficiency maximization over a wide range of wind velocities. This
paper presents the performance analysis of a wind driven double
output induction generator (DOIG) operating at varying shafts speed.
A periodic transient state analysis of DOIG equipped with two
converters is carried out using a hybrid induction machine model.
This paper simulates the harmonic content of waveforms in various
points of drive at different speeds, based on the hybrid model
(dqabc). Then the sinusoidal and trapezoidal pulse-width–modulation
control techniques are used in order to improve the power factor of
the machine and to weaken the injected low order harmonics to the
supply. Based on the frequency spectrum, total harmonics distortion,
distortion factor and power factor. Finally advantages of sinusoidal
and trapezoidal pulse width modulation techniques are compared.
Abstract: Environmental aspects plays a central role in environmental management system (EMS) because it is the basis for the identification of an organization-s environmental targets. The
existing methods for the assessment of environmental aspects are grouped into three categories: risk assessment-based (RA-based),
LCA-based and criterion-based methods. To combine the benefits of
these three categories of research, this study proposes an integrated framework, combining RA-, LCA- and criterion-based methods. The
integrated framework incorporates LCA techniques for the identification of the causal linkage for aspect, pathway, receptor and
impact, uses fuzzy logic to assess aspects, considers fuzzy conditions,
in likelihood assessment, and employs a new multi-criteria decision analysis method - multi-criteria and multi-connection comprehensive
assessment (MMCA) - to estimate significant aspects in EMS. The proposed model is verified, using a real case study and the results show
that this method successfully prioritizes the environmental aspects.
Abstract: This study aims to clarify constructions which enable to improve socio-cultural values of environments and also to obtain new knowledge on selecting development plans. CVM is adopted as a method of evaluation. As a case of the research, university campus (CP; the following) is selected on account of its various environments, institutions and many users. Investigations were conducted from 4 points of view, total value and utility value of whole CP environments, values of each environment existing in CP or development plan assumed in CP. Furthermore, respondents- attributes were also investigated. In consequence, the following is obtained. 1) Almost all of total value of CP is composed of utility value of direct use. 2) Each of environment and development plans whose value is the highest is clarified. 3) Moreover, development plan to improve environmental value the most is specified.
Abstract: Whereas in the third generation nuclear reactors,
dimensions of core and also the kind of coolant and enrichment
percent of fuel have significantly changed than the second
generation, therefore in this article the aim is based on a
comparative investigation between two same power reactors of
second and third generations, that the neutronic parameters of both
reactors such as: K∞, Keff and its details and thermal hydraulic
parameters such as: power density, specific power, volumetric heat
rate, released power per fuel volume unit, volume and mass of clad
and fuel (consisting fissile and fertile fuels), be calculated and
compared together. By this comparing the efficiency and
modification of third generation nuclear reactors than second
generation which have same power can be distinguished.
In order to calculate the cited parameters, some information
such as: core dimensions, the pitch of lattice, the fuel matter, the
percent of enrichment and the kind of coolant are used. For
calculating the neutronic parameters, a neutronic program entitled:
SIXFAC and also related formulas have been used. Meantime for
calculating the thermal hydraulic and other parameters, analytical
method and related formulas have been applied.
Abstract: In recent years, many researches to mine the exploding Web world, especially User Generated Content (UGC) such as
weblogs, for knowledge about various phenomena and events in the physical world have been done actively, and also Web services
with the Web-mined knowledge have begun to be developed for
the public. However, there are few detailed investigations on how accurately Web-mined data reflect physical-world data. It must be
problematic to idolatrously utilize the Web-mined data in public Web services without ensuring their accuracy sufficiently. Therefore,
this paper introduces the simplest Web Sensor and spatiotemporallynormalized
Web Sensor to extract spatiotemporal data about a target
phenomenon from weblogs searched by keyword(s) representing the
target phenomenon, and tries to validate the potential and reliability of the Web-sensed spatiotemporal data by four kinds of granularity
analyses of coefficient correlation with temperature, rainfall, snowfall,
and earthquake statistics per day by region of Japan Meteorological
Agency as physical-world data: spatial granularity (region-s population
density), temporal granularity (time period, e.g., per day vs. per week), representation granularity (e.g., “rain" vs. “heavy rain"), and
media granularity (weblogs vs. microblogs such as Tweets).
Abstract: Automobile Industry has great importance in the
Spanish economy (8,7 % of the active Spanish population is
employed in this sector).The above mentioned sector has been one of
the principal sectors affected by the current economic crisis,
consistently, the budgets in advertising have been severely limited
(46,9 % less in the period of reference), these needs of reduction
have originated a substantial change in the advertising strategy (from
2007 the increase of the advertising investment in Internet is 251,6
%), and increase profitability. The growing use of social media by
consumers therefore makes online consumer conversations an
attractive additional format for Automobile firms to promote
products at a lower cost. This research analyzes the relation between
the activity in Social Media and the design in the car industry,
looking for relations between strategies of design based on Social
Media and sales and a channel of information for companies to know
what the consumer preferences. For this ongoing research we used a
longitudinal withdrawal of information has been used using
information of panel. Managerial and research implications of the
finding are discussed.
Abstract: Most electrical distribution systems are incurring large
losses as the loads are wide spread, inadequate reactive power
compensation facilities and their improper control. A typical static
VAR compensator consists of capacitor bank in binary sequential
steps operated in conjunction with a thyristor controlled reactor of the
smallest step size. This SVC facilitates stepless control of reactive
power closely matching with load requirements so as to maintain
power factor nearer to unity. This type of SVC-s requiring a
appropriately controlled TCR. This paper deals with an air cored
reactor suitable for distribution transformer of 3phase, 50Hz, Dy11,
11KV/433V, 125 KVA capacity. Air cored reactors are designed,
built, tested and operated in conjunction with capacitor bank in five
binary sequential steps. It is established how the delta connected TCR
minimizes the harmonic components and the operating range for
various electrical quantities as a function of firing angle is
investigated. In particular firing angle v/s line & phase currents, D.C.
components, THD-s, active and reactive powers, odd and even triplen
harmonics, dominant characteristic harmonics are all investigated and
range of firing angle is fixed for satisfactory operation. The harmonic
spectra for phase and line quantities at specified firing angles are
given. In case the TCR is operated within the bound specified in this
paper established through simulation studies are yielding the best
possible operating condition particularly free from all dominant
harmonics.