Abstract: Pressure waves and Water Hammer occur in a
pumping system when valves are closed or opened suddenly or in
the case of sudden failure of pumps. Determination of maximum
water hammer is considered one of the most important technical
and economical items of which engineers and designers of
pumping stations and conveyance pipelines should take care.
Hammer Software is a recent application used to simulate water
hammer. The present study focuses on determining significance of
each input parameter of the application relative to the maximum
amount of water hammer estimated by the software. The study
determines estimated maximum water hammer variations due to
variations of input parameters including water temperature, pipe
type, thickness and diameter, electromotor rpm and power, and
moment of inertia of electromotor and pump. In our study,
Kuhrang Pumping Station was modeled using WaterGEMS
Software. The pumping station is characterized by total discharge
of 200 liters per second, dynamic height of 194 meters and 1.5
kilometers of steel conveyance pipeline and transports water to
Cheshme Morvarid for farmland irrigation. The model was run in
steady hydraulic condition and transferred to Hammer Software.
Then, the model was run in several unsteady hydraulic conditions
and sensitivity of maximum water hammer to each input parameter
was calculated. It is shown that parameters to which maximum
water hammer is most sensitive are moment of inertia of pump and
electromotor, diameter, type and thickness of pipe and water
temperature, 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: 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 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: This paper addresses control of commutation of switched reluctance (SR) motor without the use of a physical position detector. Rotor position detection schemes for SR motor based on magnetisation characteristics of the motor use normal excitation or applied current /voltage pulses. The resulting schemes are referred to as passive or active methods respectively. The research effort is in realizing an economical sensorless SR rotor position detector that is accurate, reliable and robust to suit a particular application. An effective and reliable means of generating commutation signals of an SR motor based on inductance profile of its stator windings determined using active probing technique is presented. The scheme has been validated online using a 4-phase 8/6 SR motor and an 8-bit processor.
Abstract: Nonlinear response behaviour of a cracked RC beam under harmonic excitation is analysed to investigate various instability phenomena like, bifurcation, jump phenomena etc. The nonlinearity of the system arises due to opening and closing of the cracks in the RC beam and is modelled as a cubic polynomial. In order to trace different branches at the bifurcation point on the response curve (amplitude versus frequency of excitation plot), an arc length continuation technique along with the incremental harmonic balance (IHBC) method is employed. The stability of the solution is investigated by the Floquet theory using Hsu-s scheme. The periodic solutions obtained by the IHBC method are compared with these obtained by the numerical integration of the equation of motion. Characteristics of solutions fold bifurcation, jump phenomena and from stable to unstable zones are identified.
Abstract: The design of chaos-based secure communication
via synchronized modified Chua-s systems is investigated in
this paper. A continuous control law is proposed to ensure
synchronization of the master and slave modified Chua-s
systems by using the variable structure control technique.
Particularly, the concept of extended systems is introduced
such that a continuous control input is obtained to avoid
chattering phenomenon. Then, it becomes possible to ensure
that the message signal embedded in the transmitter can be
recovered in the receiver.
Abstract: Since its independence in 1962, Algeria has struggled
to establish an educational system tailored to the needs of the
population it may address. Considering the historical connection with
France, Algeria has always looked at the French language as a
cultural imperative until late in the seventies. After the Arabization
policy of 1971 and the socioeconomic changes taking place
worldwide, the use of English as a communicating vehicle started to
gain more space within globalized Algeria. Consequently, disparities
in the use of French started to fade away at the cross-roads leaving
more space to the teaching of English as a second foreign language.
Moreover, the introduction of the Bologna Process and the
European Credit Transfer System in Higher Education has
necessitated some innovations in the design and development of new
curricula adapted to the socioeconomic market. In this paper, I will
try to highlight the important historical dimensions Algeria has taken
towards the implementation of an English language methodology and
to the status it acquired from second foreign language, to first foreign
language to “the language of knowledge and sciences". I will also
propose new pedagogical perspectives for a better treatment of the
English language in order to encourage independent and autonomous
learning.
Abstract: The optimal operation of proton exchange membrane fuel cell (PEMFC) requires good water management which is presented under two forms vapor and liquid. Moreover, fuel cells have to reach higher output require integration of some accessories which need electrical power. In order to analyze fuel cells operation and different species transport phenomena a biphasic mathematical model is presented by governing equations set. The numerical solution of these conservation equations is calculated by Matlab program. A multi-criteria optimization with weighting between two opposite objectives is used to determine the compromise solutions between maximum output and minimal stack size. The obtained results are in good agreement with available literature data.
Abstract: Scarcity of resources for biodiversity conservation gives rise to the need of strategic investment with priorities given to the cost of conservation. While the literature provides abundant methodological options for biodiversity conservation; estimating true cost of conservation remains abstract and simplistic, without recognising dynamic nature of the cost. Some recent works demonstrate the prominence of economic theory to inform biodiversity decisions, particularly on the costs and benefits of biodiversity however, the integration of the concept of true cost into biodiversity actions and planning are very slow to come by, and specially on a farm level. Conservation planning studies often use area as a proxy for costs neglecting different land values as well as protected areas. These literature consider only heterogeneous benefits while land costs are considered homogenous. Analysis with the assumption of cost homogeneity results in biased estimation; since not only it doesn’t address the true total cost of biodiversity actions and plans, but also it fails to screen out lands that are more (or less) expensive and/or difficult (or more suitable) for biodiversity conservation purposes, hindering validity and comparability of the results. Economies of scope” is one of the other most neglected aspects in conservation literature. The concept of economies of scope introduces the existence of cost complementarities within a multiple output production system and it suggests a lower cost during the concurrent production of multiple outputs by a given farm. If there are, indeed, economies of scope then simplistic representation of costs will tend to overestimate the true cost of conservation leading to suboptimal outcomes. The aim of this paper, therefore, is to provide first road review of the various theoretical ways in which economies of scope are likely to occur of how they might occur in conservation. Consequently, the paper addresses gaps that have to be filled in future analysis.
Abstract: This paper explores the features of political economy in the dynamics of representative politics in India. Politics is seen as enhancing economic benefits through acquiring and maintenance of power in the realm of democratic set up. The system of representation is riddled with competitive populism. Emerging leaders and parties are forced to accommodate their ideologies in coping with competitive politics. Electoral politics and voting behaviour reflect series of influences mooted by the politicians. Voters are accustomed to expect benefits outs of state exchequer. The electoral competitors show a changing phase of investment and return policy. Every elector has to spend and realize his costs in his tenure. In the case of defeated electors, even the cost recovery is not possible directly; there are indirect means to recover their costs. The series of case studies show the method of party funding, campaign financing, electoral expenditure, and cost recovery. Regulations could not restrict the level of spending. Several cases of disproportionate accumulation of wealth by the politicians reveal that money played a major part in electoral process. The political economy of representative politics hitherto ignores how a politician spends and recovers his cost and multiples his wealth. To be sure, the acquiring and maintenance of power is to enhance the wealth of the electors.
Abstract: In this paper, a near lossless image coding scheme
based on Orthogonal Polynomials Transform (OPT) has been
presented. The polynomial operators and polynomials basis operators
are obtained from set of orthogonal polynomials functions for the
proposed transform coding. The image is partitioned into a number of
distinct square blocks and the proposed transform coding is applied to
each of these individually. After applying the proposed transform
coding, the transformed coefficients are rearranged into a sub-band
structure. The Embedded Zerotree (EZ) coding algorithm is then
employed to quantize the coefficients. The proposed transform is
implemented for various block sizes and the performance is
compared with existing Discrete Cosine Transform (DCT) transform
coding scheme.
Abstract: After Apple's first introduction its smart phone, iPhone
in the end of 2009 in Korea, the number of Korean smarphone users
had been rapidly increasing so that the half of Korean population
became smart phone users as of February, 2012. Currently, smart
phones are positioned as a major digital media with powerful
influences in Korea. And, now, Koreans are leaning new information,
enjoying games and communicating other people every time and
everywhere. As smart phone devices' performances increased, the
number of usable services became more while adequate GUI
developments are required to implement various functions with smart
phones. The strategy to provide similar experiences on smart phones
through familiar features based on employment of existing media's
functions mostly contributed to smart phones' popularization in
connection with smart phone devices' iconic GUIs.
The spread of Smart phone increased mobile web accesses.
Therefore, the attempts to implement PC's web in the smart phone's
web are continuously made. The mobile web GUI provides familiar
experiences to users through designs adequately utilizing the smart
phone's GUIs. As the number of users familiarized to smart phones
and mobile web GUIs, opposite to reversed remediation from many
parts of PCs, PCs are starting to adapt smart phone GUIs.
This study defines this phenomenon as the reversed remediation,
and reviews the reversed remediation cases of Smart phone GUI'
characteristics of PCs. For this purpose, the established study issues
are as under:
· what is the reversed remediation?
· what are the smart phone GUI's characteristics?
· what kind of interrelationship exist s between the smart phone and
PC's web site?
It is meaningful in the forecast of the future GUI's change by
understanding of characteristics in the paradigm changes of PC and
smart phone's GUI designs. This also will be helpful to establish
strategies for digital devices' development and design.
Abstract: Research in e-Business has been growing
tremendously covering all related aspects such as adoption issues, e-
Business models, strategies, etc. This research aims to explore the
potential of adopting e-Business for a micro size business operating
from home called home-based businesses (HBBs). In Malaysia, the
HBB industry started many years ago and were mostly monopolized
by women or housewives managed as a part-time job to support their
family economy. Today, things have changed. The availability of the
Internet technology and the emergence of e-Business concept
promote the evolution of HBBs, which have been adopted as another
alternative as a professional career for women without neglecting
their family needs especially the children. Although this study is
confined to a limited sample size and within geographical biasness,
the findings show that it concurs with previous large scale studies. In
this study, both qualitative and quantitative methods were used and
data were gathered using triangulation methods via interview, direct
observation, document analysis and survey questionnaires. This paper
discusses the literature review, research methods and findings
pertaining to e-Business adoption factors that influence the HBBs in
Malaysia.
Abstract: The electric power industry is currently undergoing an unprecedented reform. One of the most exciting and potentially profitable recent developments is increasing usage of artificial intelligence techniques. The intention of this paper is to give an overview of using neural network (NN) techniques in power systems. According to the growth rate of NNs application in some power system subjects, this paper introduce a brief overview in fault diagnosis, security assessment, load forecasting, economic dispatch and harmonic analyzing. Advantages and disadvantages of using NNs in above mentioned subjects and the main challenges in these fields have been explained, too.
Abstract: Nowadays due to globalization of economy and
competition environment, innovation and technology plays key role
at creation of wealth and economic growth of countries. In fact
prompt growth of practical and technologic knowledge may results in
social benefits for countries when changes into effective innovation.
Considering the importance of innovation for the development of
countries, this study addresses the radical technological innovation
introduced by nanopapers at different stages of producing paper
including stock preparation, using authorized additives, fillers and
pigments, using retention, calender, stages of producing conductive
paper, porous nanopaper and Layer by layer self-assembly. Research
results show that in coming years the jungle related products will lose
considerable portion of their market share, unless embracing radical
innovation. Although incremental innovations can make this industry
still competitive in mid-term, but to have economic growth and
competitive advantage in long term, radical innovations are
necessary. Radical innovations can lead to new products and
materials which their applications in packaging industry can produce
value added. However application of nanotechnology in this industry
can be costly, it can be done in cooperation with other industries to
make the maximum use of nanotechnology possible. Therefore this
technology can be used in all the production process resulting in the
mass production of simple and flexible papers with low cost and
special properties such as facility at shape, form, easy transportation,
light weight, recovery and recycle marketing abilities, and sealing.
Improving the resistance of the packaging materials without reducing
the performance of packaging materials enhances the quality and the
value added of packaging. Improving the cellulose at nano scale can
have considerable electron optical and magnetic effects leading to
improvement in packaging and value added. Comparing to the
specifications of thermoplastic products and ordinary papers,
nanopapers show much better performance in terms of effective
mechanical indexes such as the modulus of elasticity, tensile strength,
and strain-stress. In densities lower than 640 kgm -3, due to the
network structure of nanofibers and the balanced and randomized
distribution of NFC in flat space, these specifications will even
improve more. For nanopapers, strains are 1,4Gpa, 84Mpa and 17%,
13,3 Gpa, 214Mpa and 10% respectively. In layer by layer self
assembly method (LbL) the tensile strength of nanopaper with Tio3
particles and Sio2 and halloysite clay nanotube are 30,4 ±7.6Nm/g
and 13,6 ±0.8Nm/g and 14±0.3,3Nm/g respectively that fall within
acceptable range of similar samples with virgin fiber. The usage of
improved brightness and porosity index in nanopapers can create
more competitive advantages at packaging industry.
Abstract: This paper deals with econometric analysis of real
retail trade turnover. It is a part of an extensive scientific research
about modern trends in Croatian national economy. At the end of the
period of transition economy, Croatia confronts with challenges and
problems of high consumption society. In such environment as
crucial economic variables: real retail trade turnover, average
monthly real wages and household loans are chosen for consequence
analysis. For the purpose of complete procedure of multiple
econometric analysis data base adjustment has been provided.
Namely, it has been necessary to deflate original national statistics
data of retail trade turnover using consumer price indices, as well as
provide process of seasonally adjustment of its contemporary
behavior. In model establishment it has been necessary to involve the
overcoming procedure for the autocorrelation and colinearity
problems. Moreover, for case of time-series shift a specific
appropriate econometric instrument has been applied. It would be
emphasize that the whole methodology procedure is based on the real
Croatian national economy time-series.
Abstract: Many companies have excel, it is economy and well perform to use in material requirement planning (MRP) on excel. For several products, it, however, is complex problem to link the relationship between the tables of products because the relationship depends on bill of material (BOM). This paper presents algorithm to create MRP on excel, and links relationship between tables. The study reveals MRP that is created by the algorithm which is easier and faster than MRP that created by human. By this technique, MRP on excel might be good ways to improve a productivity of companies.
Abstract: The flexible follower response of a translating cam with
four different profiles for rise-dwell-fall-dwell (RDFD) motion is
investigated. The cycloidal displacement motion, the modified
sinusoidal acceleration motion, the modified trapezoidal acceleration
motion, and the 3-4-5 polynomial motion are employed to describe the
rise and the fall motions of the follower and the associated four kinds of
cam profiles are studied. Since the follower flexibility is considered,
the contact point of the roller and the cam is an unknown. Two
geometric constraints formulated to restrain the unknown position are
substituted into Hamilton-s principle with Lagrange multipliers.
Applying the assumed mode method, one can obtain the governing
equations of motion as non-linear differential-algebraic equations. The
equations are solved using Runge-Kutta method. Then, the responses of
the flexible follower undergoing the four different motions are
investigated in time domain and in frequency domain.
Abstract: This paper employs a the variable returns to scale DEA
model to take account of risky assets and estimate the operating
efficiencies for the 21 domestic listed securities firms during the
period 2005-2009. Evidence is found that on average the brokerage
securities firms- operating efficiencies are better than integrated
securities firms. Evidence is also found that the technical inefficiency
from inappropriate management constitutes the main source of the
operating inefficiency for both types of securities firms. Moreover, the
scale economies prevail in brokerage and integrated securities firms,
in other words, which exhibit the characteristic of increasing returns to
scale.