Abstract: This paper describes an automated event detection and location system for water distribution pipelines which is based upon low-cost sensor technology and signature analysis by an Artificial
Neural Network (ANN). The development of a low cost failure sensor which measures the opacity or cloudiness of the local water
flow has been designed, developed and validated, and an ANN based system is then described which uses time series data produced by
sensors to construct an empirical model for time series prediction and
classification of events. These two components have been installed,
tested and verified in an experimental site in a UK water distribution
system. Verification of the system has been achieved from a series of
simulated burst trials which have provided real data sets. It is concluded that the system has potential in water distribution network
management.
Abstract: A design of communication area for infrared
electronic-toll-collection systems to provide an extended
communication interval in the vehicle traveling direction and
regular boundary between contiguous traffic lanes is proposed.
By utilizing two typical low-cost commercial infrared LEDs with
different half-intensity angles Φ1/2 = 22◦ and 10◦, the radiation
pattern of the emitter is designed to properly adjust the spatial
distribution of the signal power. The aforementioned purpose
can be achieved with an LED array in a three-piece structure
with appropriate mounting angles. With this emitter, the influence
of the mounting parameters, including the mounting height and
mounting angles of the on-board unit and road-side unit, on the
system performance in terms of the received signal strength and
communication area are investigated. The results reveal that, for
our emitter proposed in this paper, the ideal ”long-and-narrow”
characteristic of the communication area is very little affected by
these mounting parameters. An optimum mounting configuration is
also suggested.
Abstract: A total of 33,680 nuclear power plants (NPPs) workers were monitored and recorded from 1990 to 2007. According to the record, the average individual radiation dose has been decreasing continually from it 3.20 mSv/man in 1990 to 1.12 mSv/man at the end of 2007. After the International Commission on Radiological Protection (ICRP) 60 recommendation was generalized in South Korea, no nuclear power plant workers received above 20 mSv radiation, and the numbers of relatively highly exposed workers have been decreasing continuously. The age distribution of radiation workers in nuclear power plants was composed of mainly 20-30- year-olds (83%) for 1990 ~ 1994 and 30-40-year-olds (75%) for 2003 ~ 2007. The difference in individual average dose by age was not significant. Most (77%) of NPP radiation exposures from 1990 to 2007 occurred mostly during the refueling period. With regard to exposure type, the majority of exposures were external exposures, representing 95% of the total exposures, while internal exposures represented only 5%. External effective dose was affected mainly by gamma radiation exposure, with an insignificant amount of neutron exposure. As for internal effective dose, tritium (3H) in the pressurized heavy water reactor (PHWR) was the biggest cause of exposure.
Abstract: This paper describes new computer vision algorithms
that have been developed to track moving objects as part of a
long-term study into the design of (semi-)autonomous vehicles. We
present the results of a study to exploit variable kernels for tracking in
video sequences. The basis of our work is the mean shift
object-tracking algorithm; for a moving target, it is usual to define a
rectangular target window in an initial frame, and then process the data
within that window to separate the tracked object from the background
by the mean shift segmentation algorithm. Rather than use the
standard, Epanechnikov kernel, we have used a kernel weighted by the
Chamfer distance transform to improve the accuracy of target
representation and localization, minimising the distance between the
two distributions in RGB color space using the Bhattacharyya
coefficient. Experimental results show the improved tracking
capability and versatility of the algorithm in comparison with results
using the standard kernel. These algorithms are incorporated as part of
a robot test-bed architecture which has been used to demonstrate their
effectiveness.
Abstract: The purpose of this study was to investigate the
response of the newly released Gafchromic HD-V2 film for alpha
particle of 5.5 MeV. Gafchromic HD-V2 was exposed to alpha
particles of energy 5 MeV from 241Am for different durations. Then
the films were scanned with a flatbed scanner. The dose response
curve up to 2200 Gy has been achieved. The film’s reproducibility
and sensitivity were evaluated. The results obtained show that the net
optical density increases almost exponentially with the increase in the
exposure time, and it becomes saturated after prolonged exposure
times. The red channel shows the highest sensitivity, with a value of
4 x 10-3 Gy-1 at netOD of 0.4. The inter-film reproducibility was
measured and the relative uncertainty found was 1.7 %, 2.1 % and 2.3
% for grey, red and green channels, respectively.
Abstract: This paper describes vibration analysis using the finite
element method for a small earphone, especially for the diaphragm
shape with a low-rigidity. The viscoelastic diaphragm is supported by
multiple nonlinear concentrated springs with linear hysteresis
damping. The restoring forces of the nonlinear springs have cubic
nonlinearity. The finite elements for the nonlinear springs with
hysteresis are expressed and are connected to the diaphragm that is
modeled by linear solid finite elements in consideration of a complex
modulus of elasticity. Further, the discretized equations in physical
coordinates are transformed into the nonlinear ordinary coupled
equations using normal coordinates corresponding to the linear natural
modes. We computed the nonlinear stationary and non-stationary
responses due to the internal resonance between modes with large
amplitude in the nonlinear springs and elastic modes in the diaphragm.
The non-stationary motions are confirmed as the chaos due to the
maximum Lyapunov exponents with a positive number. From the time
histories of the deformation distribution in the chaotic vibration, we
identified nonlinear modal couplings.
Abstract: Health problems linked to urban growth are current
major concerns of developing countries. In 2002 and 2005, an
interdisciplinary program “Populations et Espaces ├á Risques
SANitaires" (PERSAN) was set up under the patronage of the
Development and Research Institute. Centered on health in
Cameroon-s urban environment, the program mainly sought to (i)
identify diarrhoea risk factors in Yaoundé, (ii) to measure their
prevalence and apprehend their spatial distribution. The crosssectional
epidemiological study that was carried out revealed a
diarrheic prevalence of 14.4% (437 cases of diarrhoea on the 3,034
children examined). Also, among risk factors studied, household
refuse management methods used by city dwellers were statistically
associated to these diarrhoeas. Moreover, it happened that levels of
diarrhoeal attacks varied consistently from one neighbourhood to
another because of the discrepancy urbanization process of the
Yaoundé metropolis.
Abstract: This paper presents a review on published literature
and experimental works on local sands for possible use as proppant,
specifically those from Terengganu coastal area. This includes
examination on characteristics of sand samples and selection of
experiments for proppant testing. Sand samples from identified areas
were tested according to particle size distribution, density, roundness
and sphericity, turbidity and mineralogy. Results from sand samples
were compared against proppant specifications set by API RP 56 and
selected commercial proppants. The present study found that the size
distribution, sphericity, turbidity and bulk density of Terengganu
sands are at par with some of commercial proppants. Nevertheless,
Terengganu sand samples do not completely surpass the required
roundness for use as proppant.
Abstract: Malaysia is aggressive in promoting the usage of ICT
to its mass population through the support by the government
policies and programs targeting the general population. However,
with the uneven distribution of the basic telecommunication
infrastructure between the urban and rural area, cost for being
“interconnected" that is considered high among the poorer rural
population and the lack of local contents that suit the rural population
needs or lifestyles, it is still a challenge for Malaysia to achieve its
Vision 2020 Agenda moving the nation towards an information
society by the year 2020. Among the existing programs that have
been carried out by the government to encourage the usage of ICT by
the rural population is “Kedaikom", a community telecenter with the
general aim is to engage the community to get exposed and to use the
ICT, encouraging the diffusion of the ICT technology to the rural
population. The research investigated by using a questionnaire
survey of how Kedaikom, as a community telecenter could play a
role in encouraging the rural or underserved community to use the
ICT. The result from the survey has proven that the community
telecenter could bridge the digital divide between the underserved
rural population and the well-accessed urban population in Malaysia.
More of the rural population, especially from the younger generation
and those with higher educational background are using the
community telecenter to be connected to the ICT.
Abstract: This paper reports on investigations into capacity of a
Multiple Input Multiple Output (MIMO) wireless communication
system employing a uniform linear array (ULA) at the transmitter and
either a uniform linear array (ULA) or a uniform circular array (UCA)
antenna at the receiver. The transmitter is assumed to be surrounded by
scattering objects while the receiver is postulated to be free from
scattering objects. The Laplacian distribution of angle of arrival
(AOA) of a signal reaching the receiver is postulated. Calculations of
the MIMO system capacity are performed for two cases without and
with the channel estimation errors. For estimating the MIMO channel,
the scaled least square (SLS) and minimum mean square error
(MMSE) methods are considered.
Abstract: For the first time since 1940 and presentation of
theodorson-s theory, distribution of thrust, torque and efficiency
along the blade of a counter rotating propeller axial fan was studied
with a novel method in this research. A constant chord, constant
pitch symmetric fan was investigated with Reynolds Stress
Turbulence method in this project and H.E.S. method was utilized to
obtain distribution profiles from C.F.D. tests outcome. C.F.D. test
results were validated by estimation from Playlic-s analytical method.
Final results proved ability of H.E.S. method to obtain distribution
profiles from C.F.D test results and demonstrated interesting facts
about effects of solidity and differences between distributions in front
and rear section.
Abstract: Operational risk has become one of the most discussed topics in the financial industry in the recent years. The reasons for this attention can be attributed to higher investments in information systems and technology, the increasing wave of mergers and acquisitions and emergence of new financial instruments. In addition, the New Basel Capital Accord (known as Basel II) demands a capital requirement for operational risk and further motivates financial institutions to more precisely measure and manage this type of risk. The aim of this paper is to shed light on main characteristics of operational risk management and common applied methods: scenario analysis, key risk indicators, risk control self assessment and loss distribution approach.
Abstract: In reality, the process observations are away from the assumption that are normal distributed. The observations could be skew distributions which should use an asymmetric chart rather than symmetric chart. Consequently, this research aim to study the robustness of the asymmetric Tukey’s control chart for skew and non-skew distributions as Lognormal and Laplace distributions. Furthermore, the performances in detecting of a change in parameter of asymmetric and symmetric Tukey’s control charts are compared by Average ARL (AARL). The results found that the asymmetric performs better than symmetric Tukey’s control chart for both cases of skew and non-skew process observation.
Abstract: The design of methods of the 20 K large dimension cold shield used for infrared radiation demarcating in space environment simulation test were introduced in this paper. The cold shield were cooled by five G-M cryocoolers , and the dimension of the cold shield is the largest in our country.Cold shield installation and distribution and compensator for contraction on cooling were introduced detailedly. The temperature distribution and cool-down time of cold shield surface were also calculated and analysed in this paper. The design of cold shield resolves the difficulty of compensator for contraction on cooling successfully. Test results show that the actual technical performance indicators of cold shield met and exceeded the design requirements.
Abstract: The paper presents an applied study of a multivariate AR(p) process fitted to daily data from U.S. commodity futures markets with the use of Bayesian statistics. In the first part a detailed description of the methods used is given. In the second part two BVAR models are chosen one with assumption of lognormal, the second with normal distribution of prices conditioned on the parameters. For a comparison two simple benchmark models are chosen that are commonly used in todays Financial Mathematics. The article compares the quality of predictions of all the models, tries to find an adequate rate of forgetting of information and questions the validity of Efficient Market Hypothesis in the semi-strong form.
Abstract: In this study, the two dimensional heat conduction
problem for the dry friction clutch disc is modeled mathematically
analysis and is solved numerically using finite element method, to
determine the temperature field when band contacts occurs between
the rubbing surfaces during the operation of an automotive clutch.
Temperature calculation have been made for contact area of different
band width and the results obtained compared with these attained
when complete contact occurs. Furthermore, the effects of slipping
time and sliding velocity function are investigated as well. Both
single and repeated engagements made at regular interval are
considered.
Abstract: A new class of percolation model in complex networks,
in which nodes are characterized by hidden variables reflecting the
properties of nodes and the occupied probability of each link is
determined by the hidden variables of the end nodes, is studied
in this paper. By the mean field theory, the analytical expressions
for the phase of percolation transition is deduced. It is determined
by the distribution of the hidden variables for the nodes and the
occupied probability between pairs of them. Moreover, the analytical
expressions obtained are checked by means of numerical simulations
on a particular model. Besides, the general model can be applied
to describe and control practical diffusion models, such as disease
diffusion model, scientists cooperation networks, and so on.
Abstract: Hierarchical Mobile IPv6 (HMIPv6) was designed to
support IP micro-mobility management in the Next Generation
Networks (NGN) framework. The main design behind this protocol is
the usage of Mobility Anchor Point (MAP) located at any level router
of network to support hierarchical mobility management. However,
the distance MAP selection in HMIPv6 causes MAP overloaded and
increase frequent binding update as the network grows. Therefore, to
address the issue in designing MAP selection scheme, we propose a
dynamic load control mechanism integrates with a speed detection
mechanism (DMS-DLC). From the experimental results we obtain
that the proposed scheme gives better distribution in MAP load and
increase handover speed.
Abstract: This paper presents the influence of preloading on a)
the contact tractions, b) slip levels and c) stresses at the dovetail
blade-disc interface of an aero-engine through a three-dimensional
(3D) finite element (FE) modeling and analysis. The preloading is
applied by an interference fit at the dovetail interface and the bulk
loading is applied through the rotational speed of rotor. Preloading at
the dovetail interface reduces the peak contact pressure developed
due to bulk loading up to 35%, and reduces the peak contact pressure
and stress difference between top and bottom contact edges.
Increasing the level of preloading reduces the cyclic stress amplitude
at the interface up to certain values of preload and as a consequence,
an improvement in fatigue life could be expected. Fretting damage,
due to vibration and wind milling effect during engine ground
condition, can be minimized by preloading the dovetail interface.
Abstract: Nowadays, the rapid development of multimedia
and internet allows for wide distribution of digital media data.
It becomes much easier to edit, modify and duplicate digital
information Besides that, digital documents are also easy to
copy and distribute, therefore it will be faced by many
threatens. It-s a big security and privacy issue with the large
flood of information and the development of the digital
format, it become necessary to find appropriate protection
because of the significance, accuracy and sensitivity of the
information. Nowadays protection system classified with more
specific as hiding information, encryption information, and
combination between hiding and encryption to increase information
security, the strength of the information hiding science is due to the
non-existence of standard algorithms to be used in hiding secret
messages. Also there is randomness in hiding methods such as
combining several media (covers) with different methods to pass a
secret message. In addition, there are no formal methods to be
followed to discover the hidden data. For this reason, the task of this
research becomes difficult. In this paper, a new system of information
hiding is presented. The proposed system aim to hidden information
(data file) in any execution file (EXE) and to detect the hidden file
and we will see implementation of steganography system which
embeds information in an execution file. (EXE) files have been
investigated. The system tries to find a solution to the size of the
cover file and making it undetectable by anti-virus software. The
system includes two main functions; first is the hiding of the
information in a Portable Executable File (EXE), through the
execution of four process (specify the cover file, specify the
information file, encryption of the information, and hiding the
information) and the second function is the extraction of the hiding
information through three process (specify the steno file, extract the
information, and decryption of the information). The system has
achieved the main goals, such as make the relation of the size of the
cover file and the size of information independent and the result file
does not make any conflict with anti-virus software.