Abstract: Due to the recovering global economy, enterprises are
increasingly focusing on logistics. Investing in logistic measures for
a production generates a large potential for achieving a good starting
point within a competitive field. Unlike during the global economic
crisis, enterprises are now challenged with investing available capital
to maximize profits. In order to be able to create an informed and
quantifiably comprehensible basis for a decision, enterprises need an
adequate model for logistically and monetarily evaluating measures
in production. The Collaborate Research Centre 489 (SFB 489) at the
Institute for Production Systems (IFA) developed a Logistic
Information System which provides support in making decisions and
is designed specifically for the forging industry. The aim of a project
that has been applied for is to now transfer this process in order to
develop a universal approach to logistically and monetarily evaluate
measures in production.
Abstract: Industrial radiography is a famous technique for the identification and evaluation of discontinuities, or defects, such as cracks, porosity and foreign inclusions found in welded joints. Although this technique has been well developed, improving both the inspection process and operating time, it does suffer from several drawbacks. The poor quality of radiographic images is due to the physical nature of radiography as well as small size of the defects and their poor orientation relatively to the size and thickness of the evaluated parts. Digital image processing techniques allow the interpretation of the image to be automated, avoiding the presence of human operators making the inspection system more reliable, reproducible and faster. This paper describes our attempt to develop and implement digital image processing algorithms for the purpose of automatic defect detection in radiographic images. Because of the complex nature of the considered images, and in order that the detected defect region represents the most accurately possible the real defect, the choice of global and local preprocessing and segmentation methods must be appropriated.
Abstract: Fixed-point simulation results are used for the
performance measure of inverting matrices by Cholesky
decomposition. The fixed-point Cholesky decomposition algorithm
is implemented using a fixed-point reconfigurable processing
element. The reconfigurable processing element provides all
mathematical operations required by Cholesky decomposition. The
fixed-point word length analysis is based on simulations using
different condition numbers and different matrix sizes. Simulation
results show that 16 bits word length gives sufficient performance
for small matrices with low condition number. Larger matrices and
higher condition numbers require more dynamic range for a fixedpoint
implementation.
Abstract: Emergence of smartphones brings to live the concept
of converged devices with the availability of web amenities. Such
trend also challenges the mobile devices manufactures and service
providers in many aspects, such as security on mobile phones,
complex and long time design flow, as well as higher development
cost. Among these aspects, security on mobile phones is getting more
and more attention. Microkernel based virtualization technology will
play a critical role in addressing these challenges and meeting mobile
market needs and preferences, since virtualization provides essential
isolation for security reasons and it allows multiple operating systems
to run on one processor accelerating development and cutting development
cost. However, virtualization benefits do not come for free.
As an additional software layer, it adds some inevitable virtualization
overhead to the system, which may decrease the system performance.
In this paper we evaluate and analyze the virtualization performance
cost of L4 microkernel based virtualization on a competitive mobile
phone by comparing the L4Linux, a para-virtualized Linux on top of
L4 microkernel, with the native Linux performance using lmbench
and a set of typical mobile phone applications.
Abstract: This paper presents a computational methodology
based on matrix operations for a computer based solution to the
problem of performance analysis of software reliability models
(SRMs). A set of seven comparison criteria have been formulated to
rank various non-homogenous Poisson process software reliability
models proposed during the past 30 years to estimate software
reliability measures such as the number of remaining faults, software
failure rate, and software reliability. Selection of optimal SRM for
use in a particular case has been an area of interest for researchers in
the field of software reliability. Tools and techniques for software
reliability model selection found in the literature cannot be used with
high level of confidence as they use a limited number of model
selection criteria. A real data set of middle size software project from
published papers has been used for demonstration of matrix method.
The result of this study will be a ranking of SRMs based on the
Permanent value of the criteria matrix formed for each model based
on the comparison criteria. The software reliability model with
highest value of the Permanent is ranked at number – 1 and so on.
Abstract: Most routing protocols (DSR, AODV etc.) that have
been designed for wireless adhoc networks incorporate the broadcasting
operation in their route discovery scheme. Probabilistic broadcasting
techniques have been developed to optimize the broadcast operation
which is otherwise very expensive in terms of the redundancy
and the traffic it generates. In this paper we have explored percolation
theory to gain a different perspective on probabilistic broadcasting
schemes which have been actively researched in the recent years.
This theory has helped us estimate the value of broadcast probability
in a wireless adhoc network as a function of the size of the network.
We also show that, operating at those optimal values of broadcast
probability there is at least 25-30% reduction in packet regeneration
during successful broadcasting.
Abstract: In this paper, a new approach based on the extent of
friendship between the nodes is proposed which makes the nodes to
co-operate in an ad hoc environment. The extended DSR protocol is
tested under different scenarios by varying the number of malicious
nodes and node moving speed. It is also tested varying the number of
nodes in simulation used. The result indicates the achieved
throughput by extended DSR is greater than the standard DSR and
indicates the percentage of malicious drops over total drops are less
in the case of extended DSR than the standard DSR.
Abstract: The response surface methodology (RSM) is a
collection of mathematical and statistical techniques useful in the
modeling and analysis of problems in which the dependent variable
receives the influence of several independent variables, in order to
determine which are the conditions under which should operate these
variables to optimize a production process. The RSM estimated a
regression model of first order, and sets the search direction using the
method of maximum / minimum slope up / down MMS U/D.
However, this method selects the step size intuitively, which can
affect the efficiency of the RSM. This paper assesses how the step
size affects the efficiency of this methodology. The numerical
examples are carried out through Monte Carlo experiments,
evaluating three response variables: efficiency gain function, the
optimum distance and the number of iterations. The results in the
simulation experiments showed that in response variables efficiency
and gain function at the optimum distance were not affected by the
step size, while the number of iterations is found that the efficiency if
it is affected by the size of the step and function type of test used.
Abstract: The present work compares the performance of three
turbulence modeling approach (based on the two-equation k -ε
model) in predicting erosive wear in multi-size dense slurry flow
through rotating channel. All three turbulence models include
rotation modification to the production term in the turbulent kineticenergy
equation. The two-phase flow field obtained numerically
using Galerkin finite element methodology relates the local flow
velocity and concentration to the wear rate via a suitable wear model.
The wear models for both sliding wear and impact wear mechanisms
account for the particle size dependence. Results of predicted wear
rates using the three turbulence models are compared for a large
number of cases spanning such operating parameters as rotation rate,
solids concentration, flow rate, particle size distribution and so forth.
The root-mean-square error between FE-generated data and the
correlation between maximum wear rate and the operating
parameters is found less than 2.5% for all the three models.
Abstract: Transaction management is one of the most crucial requirements for enterprise application development which often require concurrent access to distributed data shared amongst multiple application / nodes. Transactions guarantee the consistency of data records when multiple users or processes perform concurrent operations. Existing Fault Tolerance Infrastructure for Mobile Agents (FTIMA) provides a fault tolerant behavior in distributed transactions and uses multi-agent system for distributed transaction and processing. In the existing FTIMA architecture, data flows through the network and contains personal, private or confidential information. In banking transactions a minor change in the transaction can cause a great loss to the user. In this paper we have modified FTIMA architecture to ensure that the user request reaches the destination server securely and without any change. We have used triple DES for encryption/ decryption and MD5 algorithm for validity of message.
Abstract: The challenge for software development house in
Bangladesh is to find a path of using minimum process rather than CMMI or ISO type gigantic practice and process area. The small and medium size organization in Bangladesh wants to ensure minimum
basic Software Process Improvement (SPI) in day to day operational
activities. Perhaps, the basic practices will ensure to realize their company's improvement goals. This paper focuses on the key issues in basic software practices for small and medium size software
organizations, who are unable to effort the CMMI, ISO, ITIL etc. compliance certifications. This research also suggests a basic software process practices model for Bangladesh and it will show the mapping of our suggestions with international best practice. In this IT
competitive world for software process improvement, Small and medium size software companies that require collaboration and
strengthening to transform their current perspective into inseparable global IT scenario. This research performed some investigations and analysis on some projects- life cycle, current good practice, effective approach, reality and pain area of practitioners, etc. We did some
reasoning, root cause analysis, comparative analysis of various
approach, method, practice and justifications of CMMI and real life. We did avoid reinventing the wheel, where our focus is for minimal
practice, which will ensure a dignified satisfaction between
organizations and software customer.
Abstract: The world-s largest Pre-stressed Concrete Cylinder
Pipe (PCCP) water supply project had a series of pipe failures which
occurred between 1999 and 2001. This has led the Man-Made River
Authority (MMRA), the authority in charge of the implementation
and operation of the project, to setup a rehabilitation plan for the
conveyance system while maintaining the uninterrupted flow of
water to consumers. At the same time, MMRA recognized the need
for a long term management tool that would facilitate repair and
maintenance decisions and enable taking the appropriate preventive
measures through continuous monitoring and estimation of the
remaining life of each pipe. This management tool is known as the
Pipe Risk Management System (PRMS) and now in operation at
MMRA. Both the rehabilitation plan and the PRMS require the
availability of complete and accurate pipe construction and
manufacturing data
This paper describes a systematic approach of data collection,
analysis, evaluation and correction for the construction and
manufacturing data files of phase I pipes which are the platform for
the PRMS database and any other related decision support system.
Abstract: Whole genome duplication (WGD) increased the
number of yeast Saccharomyces cerevisiae chromosomes from 8 to
16. In spite of retention the number of chromosomes in the genome
of this organism after WGD to date, chromosomal rearrangement
events have caused an evolutionary distance between current genome
and its ancestor. Studies under evolutionary-based approaches on
eukaryotic genomes have shown that the rearrangement distance is an
approximable problem. In the case of S. cerevisiae, we describe that
rearrangement distance is accessible by using dedoubled adjacency
graph drawn for 55 large paired chromosomal regions originated
from WGD. Then, we provide a program extracted from a C program
database to draw a dedoubled genome adjacency graph for S.
cerevisiae. From a bioinformatical perspective, using the duplicated
blocks of current genome in S. cerevisiae, we infer that genomic
organization of eukaryotes has the potential to provide valuable
detailed information about their ancestrygenome.
Abstract: Power cables are vulnerable to failure due to aging or
defects that occur with the passage of time under continuous
operation and loading stresses. PD detection and characterization
provide information on the location, nature, form and extent of the
degradation. As a result, PD monitoring has become an important
part of condition based maintenance (CBM) program among power
utilities. Online partial discharge (PD) localization of defect sources
in power cable system is possible using the time of flight method.
The information regarding the time difference between the main and
reflected pulses and cable length can help in locating the partial
discharge source along the cable length. However, if the length of
the cable is not known and the defect source is located at the extreme
ends of the cable or in the middle of the cable, then double ended
measurement is required to indicate the location of PD source. Use of
multiple sensors can also help in discriminating the cable PD or local/
external PD. This paper presents the experience and results from
online partial discharge measurements conducted in the laboratory
and the challenges in partial discharge source localization.
Abstract: Due to growing environmental concerns of the cement
industry, alternative cement technologies have become an area of
increasing interest. It is now believed that new binders are
indispensable for enhanced environmental and durability
performance. Self-compacting Geopolymer concrete is an innovative
method and improved way of concreting operation that does not
require vibration for placing it and is produced by complete
elimination of ordinary Portland cement.
This paper documents the assessment of the compressive strength
and workability characteristics of low-calcium fly ash based selfcompacting
geopolymer concrete. The essential workability
properties of the freshly prepared Self-compacting Geopolymer
concrete such as filling ability, passing ability and segregation
resistance were evaluated by using Slump flow, V-funnel, L-box and
J-ring test methods. The fundamental requirements of high
flowability and segregation resistance as specified by guidelines on
Self Compacting Concrete by EFNARC were satisfied. In addition,
compressive strength was determined and the test results are included
here. This paper also reports the effect of extra water, curing time and
curing temperature on the compressive strength of self-compacting
geopolymer concrete. The test results show that extra water in the
concrete mix plays a significant role. Also, longer curing time and
curing the concrete specimens at higher temperatures will result in
higher compressive strength.
Abstract: The Non-Rotating Adjustable Stabilizer / Directional
Solution (NAS/DS) is the imitation of a mechanical process or an
object by a directional drilling operation that causes a respond
mathematically and graphically to data and decision to choose the
best conditions compared to the previous mode.
The NAS/DS Auto Guide rotary steerable tool is undergoing final
field trials. The point-the-bit tool can use any bit, work at any
rotating speed, work with any MWD/LWD system, and there is no
pressure drop through the tool. It is a fully closed-loop system that
automatically maintains a specified curvature rate.
The Non–Rotating Adjustable stabilizer (NAS) can be controls
curvature rate by exactly positioning and run with the optimum bit,
use the most effective weight (WOB) and rotary speed (RPM) and
apply all of the available hydraulic energy to the bit. The directional
simulator allowed to specify the size of the curvature rate
performance errors of the NAS tool and the magnitude of the random
errors in the survey measurements called the Directional Solution
(DS).
The combination of these technologies (NAS/DS) will provide
smoother bore holes, reduced drilling time, reduced drilling cost and
incredible targeting precision. This simulator controls curvature rate
by precisely adjusting the radial extension of stabilizer blades on a
near bit Non-Rotating Stabilizer and control process corrects for the
secondary effects caused by formation characteristics, bit and tool
wear, and manufacturing tolerances.
Abstract: Protective relays are components of a protection system
in a power system domain that provides decision making element for
correct protection and fault clearing operations. Failure of the
protection devices may reduce the integrity and reliability of the power
system protection that will impact the overall performance of the
power system. Hence it is imperative for power utilities to assess the
reliability of protective relays to assure it will perform its intended
function without failure. This paper will discuss the application of
reliability analysis using statistical method called Life Data Analysis
in Tenaga Nasional Berhad (TNB), a government linked power utility
company in Malaysia, namely Transmission Division, to assess and
evaluate the reliability of numerical overcurrent protective relays from
two different manufacturers.
Abstract: In this paper we present a soft timing phase estimation (STPE) method for wireless mobile receivers operating in low signal to noise ratios (SNRs). Discrete Polyphase Matched (DPM) filters, a Log-maximum a posterior probability (MAP) and/or a Soft-output Viterbi algorithm (SOVA) are combined to derive a new timing recovery (TR) scheme. We apply this scheme to wireless cellular communication system model that comprises of a raised cosine filter (RCF), a bit-interleaved turbo-coded multi-level modulation (BITMM) scheme and the channel is assumed to be memory-less. Furthermore, no clock signals are transmitted to the receiver contrary to the classical data aided (DA) models. This new model ensures that both the bandwidth and power of the communication system is conserved. However, the computational complexity of ideal turbo synchronization is increased by 50%. Several simulation tests on bit error rate (BER) and block error rate (BLER) versus low SNR reveal that the proposed iterative soft timing recovery (ISTR) scheme outperforms the conventional schemes.
Abstract: Green Lean Total Quality Management (TQM)
System is a system comprises of Environmental Management System
(EMS) practices which is integrated to TQM with Lean
Manufacturing (LM) principles. The ultimate goal of this system is to
focus on achieving total customer satisfaction and environmental care by removing eight wastes available in any process in an
organization. A survey questionnaire was developed and distributed to 30 highly active automotive vendors in Malaysia and analyzed by
SPSS v.17. It was found out that some vendors have been practicing TQM and LM while some have started to implement EMS. This
study is only focusing on highly active companies that have been involved in MAJAICO Program and Proton Vendor Development
Program. This is the first study conducted to know the current status of TQM, LM and EMS practices in highly active automotive companies in Malaysia. It was found out that EMS has been
practiced by 16 companies out of 30. Within these 16 companies the
approach is more holistic and green. This is a preliminary study that combined 4 awards practices, ISO/TS16949, Toyota Production
System SAEJ4000, MAJAICO Lean Production System and EMS.
Abstract: Next generation networks with the idea of convergence of service and control layer in existing networks (fixed, mobile and data) and with the intention of providing services in an integrated network, has opened new horizon for telecom operators. On the other hand, economic problems have caused operators to look for new source of income including consider new services, subscription of more users and their promotion in using morenetwork resources and easy participation of service providers or 3rd party operators in utilizing networks. With this requirement, an architecture based on next generation objectives for service layer is necessary. In this paper, a new architecture based on IMS model explains participation of 3rd party operators in creation and implementation of services on an integrated telecom network.