Abstract: After the terrorist attack on September 11, 2001 in
U.S., the container security issue got high attention, especially by U.S.
government, which deployed a lot of measures to promote or improve
security systems. U.S. government not only enhances its national
security system, but allies with other countries against the potential
terrorist attacks in the future. For example CSI (Container Security
Initiative), it encourages foreign ports outside U.S. to become CSI
ports as a part of U.S. anti-terrorism network. Although promotion of
the security could partly reach the goal of anti-terrorism, that will
influence the efficiency of container supply chain, which is the main
concern when implementing the inspection measurements. This paper
proposes a quick estimation methodology for an inspection service
rate by a berth allocation heuristic such that the inspection activities
will not affect the original container supply chain. Theoretical and
simulation results show this approach is effective.
Abstract: Laboratory classes in Electrical Engineering are often hampered by safety issues, as students have to work on high voltage lines. One solution is to make use of virtual laboratory simulations, to help students understand the concepts taught in their coursework. In this context, we have conceived and implemented virtual lab experiments in connection with the study of earthing arrangements. In this work, software was developed, which aid student in understanding the working of a residual current device (RCD) in a TT earthing system. Various parameters, such as the earthing resistances, leakage currents and harmonics were included for a TT system with RCD connection.
Abstract: This work describes a CACSD tool for automatic design of robust controllers for hydraulic turbines. The tool calculates the optimal controller using the MATLAB hinfopt function and it
serves as a practical and effective solution for the laborious task of
designing a different controller for each type of turbine and generator, and different parameters and conditions of the plant. Results of the simulation of a generating unit subject to parameters
variation show the accuracy and efficiency of the obtained robust
controllers.
Abstract: The economic and stable operation was affected
seriously by coal quality disturbance for power plants. Based on model
analysis, influence of the disturbance can be considered as gain change
of control system. Power capability coefficient of coal was
constructed to inhibit it. Accuracy of the coefficient was verified by
operating data. Then coal quality disturbance free system based on
gain scheduling was designed for coordinated control system.
Simulation showed that, the strategy improved control quality
obviously, and inhibited the coal quality disturbance.
Abstract: This paper examines long-range dependence or longmemory
of financial time series on the exchange rate data by the
fractional Brownian motion (fBm). The principle of spectral density
function in Section 2 is used to find the range of Hurst parameter (H)
of the fBm. If 0< H
Abstract: The use of sewage sludge and effluents from
wastewater treatment plants for irrigation of agricultural lands is on
the rise particularly in peri-urban areas of developing countries.
The reuse of nutrients and organic matter in treated wastewater
and sewage sludge via land application is a desirable goal. However,
trace or heavy metals present in sludge pose the risk of human or
phytotoxicity from land application. Long-term use of sewage
sludge, heavy metals can accumulate to phytotoxic levels and results
in reduced plants growth and/or enhanced metal concentrations in
plants, which consumed by animals then enter the food chain. In this
research, the amount of heavy metals was measured in plants
irrigated with wastewater and sludge application. For this purpose,
three pilots were made in a Shush treatment plant in south of Tehran.
Three plants species, spinach, lettuce and radish were selected and
planted in the pilots.First pilot was irrigated just with wastewater of
treatment plant and second pilot was irrigated with wastewater and
sludge application .Third pilot was irrigated with simulated heavy
metals solution equal 50 years of irrigation. The results indicate that
the average of amount of heavy metals Pb, Cd in three plant species
in first pilot were lower than permissible limits .In second pilot,
Cadmium accumulations are high in three species plants and more
than the standard limits. Concentration of Cd , Pb have exceed their
permitted limits in plants in third pilot . It was concluded that the use
of wastewater and sludge application in agricultural lands enriched
soils with heavy metals to concentrations that may pose potential
environmental and health risks in the long-term.
Abstract: Linear convolutive filters are fast in calculation and in application, and thus, often used for real-time processing of continuous data streams. In the case of transient signals, a filter has not only to detect the presence of a specific waveform, but to estimate its arrival time as well. In this study, a measure is presented which indicates the performance of detectors in achieving both of these tasks simultaneously. Furthermore, a new sub-class of linear filters within the class of filters which minimize the quadratic response is proposed. The proposed filters are more flexible than the existing ones, like the adaptive matched filter or the minimum power distortionless response beamformer, and prove to be superior with respect to that measure in certain settings. Simulations of a real-time scenario confirm the advantage of these filters as well as the usefulness of the performance measure.
Abstract: The aim of this study was to evaluate the effect of preexercise glycerol hyperhydration on endurance performance in a heat chamber designed to simulate the World Championship Distance (WCD) duathlon (10km run, 40km ride, 5 km run). Duathlons are often performed in hot and humid conditions and as a result hydration is a major issue. Glycerol enhances the body’s capacity for fluid retention by inducing hyperhydration, which is theorized to improve thermoregulatory and cardiovascular responses, and thereby improve performance. Six well-trained athletes completed the testing protocol in a heat chamber at the La Trobe University Exercise Physiology Laboratory. Each testing session was approximately 4.5 hours in duration (2 hours of pre-exercise glycerol hyper-hydration followed by approximately 2.5 hours of exercise). The results showed an increased water retention pre-exercise and an improved overall performance of 2.04% was achieved by subjects ingesting the glycerol solution.
Abstract: The objective of this contribution is to study the
performances in terms of bit error rate, of space-time code algorithms
applied to MIMO communication in tunnels. Indeed, the channel
characteristics in a tunnel are quite different than those of urban or
indoor environment, due to the guiding effect of the tunnel.
Therefore, MIMO channel matrices have been measured in a straight
tunnel, in a frequency band around 3GHz. Correlation between array
elements and properties of the MIMO matrices are first studied as a
function of the distance between the transmitter and the receiver.
Then, owing to a software tool simulating the link, predicted values
of bit error rate are given for VLAST, OSTBC and QSTBC
algorithms applied to a MIMO configuration with 2 or 4 array
elements. Results are interpreted from the analysis of the channel
properties.
Abstract: FACTS devices are used to control the power flow, to
increase the transmission capacity and to optimize the stability of the
power system. One of the most widely used FACTS devices is
Unified Power Flow Controller (UPFC). The controller used in the
control mechanism has a significantly effects on controlling of the
power flow and enhancing the system stability of UPFC. According
to this, the capability of UPFC is observed by using different control
mechanisms based on P, PI, PID and fuzzy logic controllers (FLC) in
this study. FLC was developed by taking consideration of Takagi-
Sugeno inference system in the decision process and Sugeno-s
weighted average method in the defuzzification process. Case studies
with different operating conditions are applied to prove the ability of
UPFC on controlling the power flow and the effectiveness of
controllers on the performance of UPFC. PSCAD/EMTDC program
is used to create the FLC and to simulate UPFC model.
Abstract: In Secondary Surveillance Radar (SSR) systems, it is
more difficult to locate and recognise aircrafts in the neighbourhood of civil airports since aerial traffic becomes greater. Here, we propose to apply a recent Blind Source Separation (BSS) algorithm based
on Time-Frequency Analysis, in order to separate messages sent by different aircrafts and falling in the same radar beam in reception. The above source separation method involves joint-diagonalization
of a set of smoothed version of spatial Wigner-Ville distributions.
The technique makes use of the difference in the t-f signatures of the nonstationary sources to be separated. Consequently, as the SSR sources emit different messages at different frequencies, the above fitted to this new application. We applied the technique in simulation to separate SSR replies. Results are provided at the end
of the paper.
Abstract: There is a world-wide need for the development of sustainable management strategies to control pest infestation and the development of phosphine (PH3) resistance in lesser grain borer (Rhyzopertha dominica). Computer simulation models can provide a relatively fast, safe and inexpensive way to weigh the merits of various management options. However, the usefulness of simulation models relies on the accurate estimation of important model parameters, such as mortality. Concentration and time of exposure are both important in determining mortality in response to a toxic agent. Recent research indicated the existence of two resistance phenotypes in R. dominica in Australia, weak and strong, and revealed that the presence of resistance alleles at two loci confers strong resistance, thus motivating the construction of a two-locus model of resistance. Experimental data sets on purified pest strains, each corresponding to a single genotype of our two-locus model, were also available. Hence it became possible to explicitly include mortalities of the different genotypes in the model. In this paper we described how we used two generalized linear models (GLM), probit and logistic models, to fit the available experimental data sets. We used a direct algebraic approach generalized inverse matrix technique, rather than the traditional maximum likelihood estimation, to estimate the model parameters. The results show that both probit and logistic models fit the data sets well but the former is much better in terms of small least squares (numerical) errors. Meanwhile, the generalized inverse matrix technique achieved similar accuracy results to those from the maximum likelihood estimation, but is less time consuming and computationally demanding.
Abstract: In this paper, the difference between the Alternating
Direction Method (ADM) and the Non-Splitting Method (NSM) is
investigated, while both methods applied to the simulations for 2-D
multimaterial radiation diffusion issues. Although the ADM have the
same accuracy orders with the NSM on the uniform meshes, the
accuracy of ADM will decrease on the distorted meshes or the
boundary of domain. Numerical experiments are carried out to
confirm the theoretical predication.
Abstract: Numerical study is performed to investigate the
temperature distribution in an annular diffuser fitted with helical tape
hub. Different pitches (Y = 20 mm, and Y = 30 mm) for the helical
tape are studied with different heights (H = 20 mm, 22 mm, and 24
mm) to be compared. The geometry of the annular diffuser and the
inlet condition for both hub arrangements are kept constant. The
result obtains that using helical tape insert with different pitches and
different heights will force the temperature to distribute in a helical
direction; however the use of helical tape hub with height (H = 22
mm) for both pitches enhance the temperature distribution in a good
manner.
Abstract: The scroll pump belongs to the category of positive
displacement pump can be used for continuous pumping of gases at
low pressure apart from general vacuum application. The shape of
volume occupied by the gas moves and deforms continuously as the
spiral orbits. To capture flow features in such domain where mesh
deformation varies with time in a complicated manner, mesh less
solver was found to be very useful. Least Squares Kinetic Upwind
Method (LSKUM) is a kinetic theory based mesh free Euler solver
working on arbitrary distribution of points. Here upwind is enforced
in molecular level based on kinetic flux vector splitting scheme
(KFVS). In the present study we extended the LSKUM to moving
node viscous flow application. This new code LSKUM-NS-MN for
moving node viscous flow is validated for standard airfoil pitching
test case. Simulation performed for flow through scroll pump using
LSKUM-NS-MN code agrees well with the experimental pumping
speed data.
Abstract: For today-s and future wireless communications applications,
more and more data traffic has to be transmitted with
growing speed and quality demands. The analog front-end of any
mobile device has to cope with very hard specifications regardless
which transmission standard has to be supported. State-of-the-art
analog front-end implementations are reaching the limit of technical
feasibility. For that reason, alternative front-end architectures could
support a continuing development of mobile communications e.g.,
six-port-based front-ends [1], [2].
In this article we propose an analog front-end with high intermediate
frequency and which utilizes additive mixing instead
of multiplicative mixing. The system architecture is presented and
several spurious effects as well as their influence on the system
dimensioning are discussed. Furthermore, several issues concerning
the technical feasibility are provided and some simulation results
are discussed which show the principle functionality of the proposed
superposition heterodyne receiver.
Abstract: The VoIP networks as alternative method to traditional PSTN system has been implemented in a wide variety of structures
with multiple protocols, codecs, software and hardware–based
distributions. The use of cryptographic techniques let the users to have a secure communication, but the calculate throughput as well as the QoS parameters are affected according to the used algorithm. This
paper analyzes the VoIP throughput and the QoS parameters with
different commercial encryption methods. The measurement–based
approach uses lab scenarios to simulate LAN and WAN
environments. Security mechanisms such as TLS, SIAX2, SRTP,
IPSEC and ZRTP are analyzed with μ-LAW and GSM codecs.
Abstract: The use of Quantum dots is a promising emerging
Technology for implementing digital system at the nano level. It is
effecient for attractive features such as faster speed , smaller size and
low power consumption than transistor technology. In this paper,
various Combinational and sequential logical structures - HALF
ADDER, SR Latch and Flip-Flop, D Flip-Flop preceding NAND,
NOR, XOR,XNOR are discussed based on QCA design, with
comparatively less number of cells and area. By applying these
layouts, the hardware requirements for a QCA design can be reduced.
These structures are designed and simulated using QCA Designer
Tool. By taking full advantage of the unique features of this
technology, we are able to create complete circuits on a single layer
of QCA. Such Devices are expected to function with ultra low
power Consumption and very high speeds.
Abstract: In this paper, for the understanding of the phytoplankton dynamics in marine ecosystem, a susceptible and an infected class of phytoplankton population is considered in spatiotemporal domain.
Here, the susceptible phytoplankton is growing logistically and the
growth of infected phytoplankton is due to the instantaneous Holling
type-II infection response function. The dynamics are studied in terms of the local and global stabilities for the system and further
explore the possibility of Hopf -bifurcation, taking the half saturation period as (i.e., ) the bifurcation parameter in temporal domain.
It is also observe that the reaction diffusion system exhibits spatiotemporal
chaos and pattern formation in phytoplankton dynamics,
which is particularly important role play for the spatially extended phytoplankton system. Also the effect of the diffusion coefficient
on the spatial system for both one and two dimensional case is obtained. Furthermore, we explore the higher-order stability analysis
of the spatial phytoplankton system for both linear and no-linear system. Finally, few numerical simulations are carried out for pattern
formation.
Abstract: The InAlGaN alloy has only recently began receiving
serious attention into its growth and application. High quality InGaN
films have led to the development of light emitting diodes (LEDs) and
blue laser diodes (LDs). The quaternary InAlGaN however, represents
a more versatile material since the bandgap and lattice constant can be
independently varied. We report an ultraviolet (UV) quaternary
InAlGaN multi-quantum wells (MQWs) LD study by using the
simulation program of Integrated System Engineering (ISE TCAD).
Advanced physical models of semiconductor properties were used in
order to obtain an optimized structure. The device performance which
is affected by piezoelectric and thermal effects was studied via
drift-diffusion model for carrier transport, optical gain and loss. The
optical performance of the UV LD with different numbers of quantum
wells was numerically investigated. The main peak of the emission
wavelength for double quantum wells (DQWs) was shifted from 358
to 355.8 nm when the forward current was increased. Preliminary
simulated results indicated that better output performance and lower
threshold current could be obtained when the quantum number is four,
with output power of 130 mW and threshold current of 140 mA.