Abstract: The heuristic decision rules used for project
scheduling will vary depending upon the project-s size, complexity,
duration, personnel, and owner requirements. The concept of project
complexity has received little detailed attention. The need to
differentiate between easy and hard problem instances and the
interest in isolating the fundamental factors that determine the
computing effort required by these procedures inspired a number of
researchers to develop various complexity measures.
In this study, the most common measures of project complexity are
presented. A new measure of project complexity is developed. The
main privilege of the proposed measure is that, it considers size,
shape and logic characteristics, time characteristics, resource
demands and availability characteristics as well as number of critical
activities and critical paths. The degree of sensitivity of the proposed
measure for complexity of project networks has been tested and
evaluated against the other measures of complexity of the considered
fifty project networks under consideration in the current study. The
developed measure showed more sensitivity to the changes in the
network data and gives accurate quantified results when comparing
the complexities of networks.
Abstract: Self-Excited Induction Generator (SEIG) builds up voltage while it enters in its magnetic saturation region. Due to non-linear magnetic characteristics, the performance analysis of SEIG involves cumbersome mathematical computations. The dependence of air-gap voltage on saturated magnetizing reactance can only be established at rated frequency by conducting a laboratory test commonly known as synchronous run test. But, there is no laboratory method to determine saturated magnetizing reactance and air-gap voltage of SEIG at varying speed, terminal capacitance and other loading conditions. For overall analysis of SEIG, prior information of magnetizing reactance, generated frequency and air-gap voltage is essentially required. Thus, analytical methods are the only alternative to determine these variables. Non-existence of direct mathematical relationship of these variables for different terminal conditions has forced the researchers to evolve new computational techniques. Artificial Neural Networks (ANNs) are very useful for solution of such complex problems, as they do not require any a priori information about the system. In this paper, an attempt is made to use cascaded neural networks to first determine the generated frequency and magnetizing reactance with varying terminal conditions and then air-gap voltage of SEIG. The results obtained from the ANN model are used to evaluate the overall performance of SEIG and are found to be in good agreement with experimental results. Hence, it is concluded that analysis of SEIG can be carried out effectively using ANNs.
Abstract: A heuristic conceptual model for to develop the
Reliability Centered Maintenance (RCM), especially in preventive
strategy, has been explored during this paper. In most real cases
which complicity of system obligates high degree of reliability, this
model proposes a more appropriate reliability function between life
time distribution based and another which is based on relevant
Extreme Value (EV) distribution. A statistical and mathematical
approach is used to estimate and verify these two distribution
functions. Then best one is chosen just among them, whichever is
more reliable. A numeric Industrial case study will be reviewed to
represent the concepts of this paper, more clearly.
Abstract: This paper discusses EM algorithm and Bootstrap
approach combination applied for the improvement of the satellite
image fusion process. This novel satellite image fusion method based
on estimation theory EM algorithm and reinforced by Bootstrap
approach was successfully implemented and tested. The sensor
images are firstly split by a Bayesian segmentation method to
determine a joint region map for the fused image. Then, we use the
EM algorithm in conjunction with the Bootstrap approach to develop
the bootstrap EM fusion algorithm, hence producing the fused
targeted image. We proposed in this research to estimate the
statistical parameters from some iterative equations of the EM
algorithm relying on a reference of representative Bootstrap samples
of images. Sizes of those samples are determined from a new
criterion called 'hybrid criterion'. Consequently, the obtained results
of our work show that using the Bootstrap EM (BEM) in image
fusion improve performances of estimated parameters which involve
amelioration of the fused image quality; and reduce the computing
time during the fusion process.
Abstract: This research paper evaluates and compares the
performance of equal cost adaptive multi-path routing algorithms
taking the transport protocols TCP (Transmission Control Protocol)
and UDP (User Datagram Protocol) using network simulator ns2 and
concludes which one is better.
Abstract: Recently, an enhanced hexagon-based search (EHS)
algorithm was proposed to speedup the original hexagon-based search
(HS) by exploiting the group-distortion information of some evaluated
points. In this paper, a second version of the EHS is proposed with a
new point-oriented inner search technique which can further speedup
the HS in both large and small motion environments. Experimental
results show that the enhanced hexagon-based search version-2
(EHS2) is faster than the HS up to 34% with negligible PSNR
degradation.
Abstract: The previous proposed evacuation routing approaches usually divide the space into multiple interlinked zones. However, it may be harder to clearly and objectively define the margins of each zone. This paper proposes an approach that connects locations of necessary guidance into a spatial network. In doing so, evacuation routes can be constructed based on the links between starting points, turning nodes, and terminal points. This approach more conforms to the real-life evacuation behavior. The feasibility of the proposed approach is evaluated through a case of one floor in a hospital building. Results indicate that the proposed approach provides valuable suggestions for evacuation planning.
Abstract: The main aim of this paper is to present the research
findings on the solution of centralized Web-Services for students by
adopting a framework and a prototype for Service Oriented
Architecture (SOA) Web-Services. The current situation of students-
Web-based application services has been identified and proposed an
effective SOA to increase the operational efficiency of Web-Services
for them it was necessary to identify the challenges in delivering a
SOA technology to increase operational efficiency of Web-Services.
Moreover, the SOA is an emerging concept, used for delivering
efficient student SOA Web-Services. Therefore, service reusability
from SOA Web-Services is provided and logically divided services
into smaller services to increase reusability and modularity. In this
case each service is a modular unit by itself and interoperability
services.
Abstract: The index of sustainable functionality (ISF) is an adaptive, multi-criteria technique that is used to measure sustainability; it is a concept that can be transposed to many regions throughout the world. An ISF application of the Southern Regional Organisation of Councils (SouthROC) in South East Queensland (SEQ) – the fastest growing region in Australia – indicated over a 25 year period an increase of over 10% level of functionality from 58.0% to 68.3%. The ISF of SouthROC utilised methodologies that derived from an expert panel based approach. The overall results attained an intermediate level of functionality which amounted to related concerns of economic progress and lack of social awareness. Within the region, a solid basis for future testing by way of measured changes and developed trends can be established. In this regard as management tool, the ISF record offers support for regional sustainability practice and decision making alike. This research adaptively analyses sustainability – a concept that is lacking throughout much of the academic literature and any reciprocal experimentation. This lack of knowledge base has been the emphasis of where future sustainability research can grow from and prove useful in rapidly growing regions. It is the intentions of this research to help further develop the notions of index-based quantitative sustainability.
Abstract: A feed-forward, back-propagation Artificial Neural
Network (ANN) model has been used to forecast the occurrences of
wastewater overflows in a combined sewerage reticulation system.
This approach was tested to evaluate its applicability as a method
alternative to the common practice of developing a complete
conceptual, mathematical hydrological-hydraulic model for the
sewerage system to enable such forecasts. The ANN approach
obviates the need for a-priori understanding and representation of the
underlying hydrological hydraulic phenomena in mathematical terms
but enables learning the characteristics of a sewer overflow from the
historical data.
The performance of the standard feed-forward, back-propagation
of error algorithm was enhanced by a modified data normalizing
technique that enabled the ANN model to extrapolate into the
territory that was unseen by the training data. The algorithm and the
data normalizing method are presented along with the ANN model
output results that indicate a good accuracy in the forecasted sewer
overflow rates. However, it was revealed that the accurate
forecasting of the overflow rates are heavily dependent on the
availability of a real-time flow monitoring at the overflow structure
to provide antecedent flow rate data. The ability of the ANN to
forecast the overflow rates without the antecedent flow rates (as is
the case with traditional conceptual reticulation models) was found to
be quite poor.
Abstract: The utilization of renewable energy sources in electric
power systems is increasing quickly because of public apprehensions
for unpleasant environmental impacts and increase in the energy
costs involved with the use of conventional energy sources. Despite
the application of these energy sources can considerably diminish the
system fuel costs, they can also have significant influence on the
system reliability. Therefore an appropriate combination of the
system reliability indices level and capital investment costs of system
is vital. This paper presents a hybrid wind/photovoltaic plant, with
the aim of supplying IEEE reliability test system load pattern while
the plant capital investment costs is minimized by applying a hybrid
particle swarm optimization (PSO) / harmony search (HS) approach,
and the system fulfills the appropriate level of reliability.
Abstract: The advances in wireless communication have opened unlimited horizons but there are some challenges as well. The Nature derived air medium between MS (Mobile Station) and BS (Base Station) is beyond human control and produces channel impairment. The impact of the natural conditions at the air medium is the biggest issue in wireless communication. Natural conditions make reliability more cumbersome; here reliability refers to the efficient recovery of the lost or erroneous data. The SR-ARQ (Selective Repeat-Automatic Repeat Request) protocol is a de facto standard for any wireless technology at the air interface with its standard reliability features. Our focus in this research is on the reliability of the control or feedback signal of the SR-ARQ protocol. The proposed mechanism, RSR-ARQ (Reliable SR-ARQ) is an enhancement of the SR-ARQ protocol that has ensured the reliability of the control signals through channel impairment sensitive mechanism. We have modeled the system under two-state discrete time Markov Channel. The simulation results demonstrate the better recovery of the lost or erroneous data that will increase the overall system performance.
Abstract: Giving birth is a natural process and most women have to go through it. Gynecologist or Midwife usually uses the leg holder to position the cervix in the stitching process. In some part of rural areas in Indonesia, the labor process normally being done at homes by calling in a midwife or gynecologist. The facilities for this kind of labor process is not yet sufficient, as the use of leg holder supposedly on the obstetric bed. The reality is that it is impossible to bring in the obstetric bed to the patient-s house at the time they call for giving birth or the time when the stitching of the cervix need to be done. This research is redesigning the leg holder through Biomechanics and ergonomic approaches to obtain the optimal design which is suitable to the user of a developing country such as Indonesia.
Abstract: Directional over current relays (DOCR) are commonly used in power system protection as a primary protection in distribution and sub-transmission electrical systems and as a secondary protection in transmission systems. Coordination of protective relays is necessary to obtain selective tripping. In this paper, an approach for efficiency reduction of DOCRs nonlinear optimum coordination (OC) is proposed. This was achieved by modifying the objective function and relaxing several constraints depending on the four constraints classification, non-valid, redundant, pre-obtained and valid constraints. According to this classification, the far end fault effect on the objective function and constraints, and in consequently on relay operating time, was studied. The study was carried out, firstly by taking into account the near-end and far-end faults in DOCRs coordination problem formulation; and then faults very close to the primary relays (nearend faults). The optimal coordination (OC) was achieved by simultaneously optimizing all variables (TDS and Ip) in nonlinear environment by using of Genetic algorithm nonlinear programming techniques. The results application of the above two approaches on 6-bus and 26-bus system verify that the far-end faults consideration on OC problem formulation don-t lose the optimality.
Abstract: Apart from geometry, functionality is one of the most
significant hallmarks of a product. The functionality of a product can
be considered as the fundamental justification for a product
existence. Therefore a functional analysis including a complete and
reliable descriptor has a high potential to improve product
development process in various fields especially in knowledge-based
design. One of the important applications of the functional analysis
and indexing is in retrieval and design reuse concept. More than 75%
of design activity for a new product development contains reusing
earlier and existing design know-how. Thus, analysis and
categorization of product functions concluded by functional
indexing, influences directly in design optimization. This paper
elucidates and evaluates major classes for functional analysis by
discussing their major methods. Moreover it is finalized by
presenting a noble hybrid approach for functional analysis.
Abstract: The evolution of technology and construction techniques has enabled the upgrading of transport networks. In particular, the high-speed rail networks allow convoys to peak at above 300 km/h. These structures, however, often significantly impact the surrounding environment. Among the effects of greater importance are the ones provoked by the soundwave connected to train transit. The wave propagation affects the quality of life in areas surrounding the tracks, often for several hundred metres. There are substantial damages to properties (buildings and land), in terms of market depreciation. The present study, integrating expertise in acoustics, computering and evaluation fields, outlines a useful model to select project paths so as to minimize the noise impact and reduce the causes of possible litigation. It also facilitates the rational selection of initiatives to contain the environmental damage to the already existing railway tracks. The research is developed with reference to the Italian regulatory framework (usually more stringent than European and international standards) and refers to a case study concerning the high speed network in Italy.
Abstract: In this paper, we use nonlinear system identification method to predict and detect process fault of a cement rotary kiln. After selecting proper inputs and output, an input-output model is identified for the plant. To identify the various operation points in the
kiln, Locally Linear Neuro-Fuzzy (LLNF) model is used. This model is trained by LOLIMOT algorithm which is an incremental treestructure
algorithm. Then, by using this method, we obtained 3
distinct models for the normal and faulty situations in the kiln. One of the models is for normal condition of the kiln with 15 minutes
prediction horizon. The other two models are for the two faulty situations in the kiln with 7 minutes prediction horizon are presented.
At the end, we detect these faults in validation data. The data collected from White Saveh Cement Company is used for in this study.
Abstract: Natural frequencies and dynamic response of a spur
gear sector are investigated using a two dimensional finite element
model that offers significant advantages for dynamic gear analyses.
The gear teeth are analyzed for different operating speeds. A primary
feature of this modeling is determination of mesh forces using a
detailed contact analysis for each time step as the gears roll through
the mesh. Transient mode super position method has been used to
find horizontal and vertical components of displacement and
dynamic stress. The finite element analysis software ANSYS has
been used on the proposed model to find the natural frequencies by
Block Lanczos technique and displacements and dynamic stresses by
transient mode super position method. A comparison of theoretical
(natural frequency and static stress) results with the finite element
analysis results has also been done. The effect of rotational speed of
the gears on the dynamic response of gear tooth has been studied and
design limits have been discussed.
Abstract: The transient hydrodynamics and thermal behaviors of
fluid flow in open-ended vertical parallel-plate porous microchannel are investigated semi-analytically under the effect of the hyperbolic
heat conduction model. The model that combines both the continuum approach and the possibility of slip at the boundary is adopted in the
study. The Effects of Knudsen number , Darcy number , and thermal relaxation time on the microchannel hydrodynamics and thermal behaviors are investigated using the hyperbolic heat
conduction models. It is found that as increases the slip in the hydrodynamic and thermal boundary condition increases. This slip in
the hydrodynamic boundary condition increases as increases. Also, the slip in the thermal boundary condition increases as
decreases especially the early stage of time.
Abstract: This paper presents an analytical solution to get a reliable estimation of the hydrodynamic pressure on gravity dams induced by vertical component earthquake when solving the fluid and dam interaction problem. Presented analytical technique is presented for calculation of earthquake-induced hydrodynamic pressure in the reservoir of gravity dams allowing for water compressibility and wave absorption at the reservoir bottom. This new analytical solution can take into account the effect of bottom material on seismic response of gravity dams. It is concluded that because the vertical component of ground motion causes significant hydrodynamic forces in the horizontal direction on a vertical upstream face, responses to the vertical component of ground motion are of special importance in analysis of concrete gravity dams subjected to earthquakes.