Abstract: In a recent year usage of VoIP subscription has increased tremendously as compare to Public Switching Telephone System(PSTN). A VoIP subscriber would like to know the exact tariffs of the calls made using VoIP. As the usage increases, the rate of fraud is also increases, causing users complain about excess billing. This in turn hampers the growth of VoIP .This paper describe the common frauds and attack on VoIP based system and make an attempt to solve the billing attack by creating secured channel between caller and callee.
Abstract: All the available algorithms for blind estimation namely constant modulus algorithm (CMA), Decision-Directed Algorithm (DDA/DFE) suffer from the problem of convergence to local minima. Also, if the channel drifts considerably, any DDA looses track of the channel. So, their usage is limited in varying channel conditions. The primary limitation in such cases is the requirement of certain overhead bits in the transmit framework which leads to wasteful use of the bandwidth. Also such arrangements fail to use channel state information (CSI) which is an important aid in improving the quality of reception. In this work, the main objective is to reduce the overhead imposed by the pilot symbols, which in effect reduces the system throughput. Also we formulate an arrangement based on certain dynamic Artificial Neural Network (ANN) topologies which not only contributes towards the lowering of the overhead but also facilitates the use of the CSI. A 2×2 Multiple Input Multiple Output (MIMO) system is simulated and the performance variation with different channel estimation schemes are evaluated. A new semi blind approach based on dynamic ANN is proposed for channel tracking in varying channel conditions and the performance is compared with perfectly known CSI and least square (LS) based estimation.
Abstract: In this paper we present high performance
dynamically allocated multi-queue (DAMQ) buffer schemes for fault
tolerance systems on chip applications that require an interconnection
network. Two virtual channels shared the same buffer space. Fault
tolerant mechanisms for interconnection networks are becoming a
critical design issue for large massively parallel computers. It is also
important to high performance SoCs as the system complexity keeps
increasing rapidly. On the message switching layer, we make
improvement to boost system performance when there are faults
involved in the components communication. The proposed scheme is
when a node or a physical channel is deemed as faulty, the previous
hop node will terminate the buffer occupancy of messages destined
to the failed link. The buffer usage decisions are made at switching
layer without interactions with higher abstract layer, thus buffer
space will be released to messages destined to other healthy nodes
quickly. Therefore, the buffer space will be efficiently used in case
fault occurs at some nodes.
Abstract: In order to enhance the usability of the human computer interface (HCI) on the touchscreen, this study explored the optimal tactile depth and effect of visual cues on the user-s tendency to touch the touchscreen icons. The experimental program was designed on the touchscreen in this study. Results indicated that the ratio of the icon size to the tactile depth was 1:0.106. There were significant effects of experienced users and novices on the tactile feedback depth (p < 0.01). In addition, the results proved that the visual cues provided a feedback that helped to guide the user-s touch icons accurately and increased the capture efficiency for a tactile recognition field. This tactile recognition field was 18.6 mm in length. There was consistency between the experienced users and novices under the visual cue effects. Finally, the study developed an applied design with touch feedback for touchscreen icons.
Abstract: In this study, the dispersed model is used to predict
gas phase concentration, liquid drop concentration. The venturi
scrubber efficiency is calculated by gas phase concentration. The
modified model has been validated with available experimental data
of Johnstone, Field and Tasler for a range of throat gas velocities,
liquid to gas ratios and particle diameters and is used to study the
effect of some design parameters on collection efficiency.
Abstract: Accounts of language acquisition differ significantly in their treatment of the role of prediction in language learning. In particular, nativist accounts posit that probabilistic learning about words and word sequences has little to do with how children come to use language. The accuracy of this claim was examined by testing whether distributional probabilities and frequency contributed to how well 3-4 year olds repeat simple word chunks. Corresponding chunks were the same length, expressed similar content, and were all grammatically acceptable, yet the results of the study showed marked differences in performance when overall distributional frequency varied. It was found that a distributional model of language predicted the empirical findings better than a number of other models, replicating earlier findings and showing that children attend to distributional probabilities in an adult corpus. This suggested that language is more prediction-and-error based, rather than on abstract rules which nativist camps suggest.
Abstract: The biological activity of A. pullulans isolates against
species of the genus Fusarium, bacteria of the genus Azotobacter and
pseudomonads colonizing wheat kernels was evaluated. A field
experiment was carried out in 2009-2011, in north-eastern Poland.
Winter wheat (cv. Bogatka) plants were sprayed with a cell
suspension of A. pullulans at a density of 106 - 108 per cm3 water at
the stem elongation stage and the heading stage. Untreated plants
served as control. The abundance of epiphytic yeasts, bacteria of the
genus Azotobacter, pseudomonads and Fusarium pathogens on wheat
grain was estimated at harvest and after six months’ storage. The
average size of yeast communities was significantly greater on wheat
kernels treated with a cell suspension of A. pullulans, compared with
control samples. In 2010-2011, biological control reduced the
abundance of some species of the genus Fusarium.
Abstract: The Kowsar dam supply water for different usages
such as drinking, industrial, agricultural and aquaculture farms
usages and located next to the city of Dehdashat in Kohgiluye and
Boyerahmad province in southern Iran. There are some towns and
villages on the Kowsar dam watersheds, which Dehdasht and Choram
are the most important and populated cities in this area. The study
was undertaken to assess the status of water quality in the urban areas
of the Kowsar dam. A total of 28 water samples were collected from
6 stations on surface water and 1 station from groundwater on the
watershed of the Kowsar dam. All the samples were analyzed for Ni
concentration using standard procedures. The results were compared
with other national and international standards. Among the analyzed
samples, as the maximum value of Nickel (0.01 mg/L) was observed
on the station 2 at the autumn 2010, all the samples analyzed were
within the maximum admissible limits by the United States
Environmental Protection Agency, EU, WHO and the Iranian. In
general results of the present study have shown that a Ni mean value
of station No. 2 with 0.006 mg/L is higher than the other stations. Ni
level of all samples and stations have had normal values and this is an
indication of pollution potential and hazards because of human
activity and waste water of towns in the areas, which can effect on
human health implications in future. This research, therefore,
recommends the government and other responsible authorities to take
suitable improving measures in the Kowsar dam watersheds.
Abstract: Bicycle usage for exercise, recreation, and commuting
to work in Australia shows that pedal cycling is the fourth most
popular activity with 10.6% increase in participants between 2001
and 2007. As with other means of transport, accident and injury
becomes common although mandatory bicycle helmet wearing has
been introduced. The research aims to develop a face surrogate made
of sandwich of rigid foam and rubber sheets to represent human
facial bone under blunt impact. The facial surrogate will serve as an
important test device for further development of facial-impact
protection for cyclist. A test procedure was developed to simulate the
energy of impact and record data to evaluate the effect of impact on
facial bones. Drop tests were performed to establish a suitable
combination of materials. It was found that the sandwich structure of
rigid extruded-polystyrene foam (density of 40 kg/m3 with a pattern
of 6-mm-holes), Neoprene rubber sponge, and Abrasaflex rubber
backing, had impact characteristics comparable to that of human
facial bone. In particular, the foam thickness of 30 mm and 25 mm
was found suitable to represent human zygoma (cheekbone) and
maxilla (upper-jaw bone), respectively.
Abstract: In the present Jordan hotels scenario, service quality is
a vital competitive policy to keep customer support and build great
base. Hotels are trying to win customer loyalty by providing enhanced
quality services. This paper attempts to examine the impact of tourism
service quality dimension in the Jordanian five star hotels. A total of
322 surveys were administrated to tourists who were staying at three
branches Marriott hotel in Jordan. The results show that dimensions of
service quality such as empathy, reliability, responsiveness and
tangibility significantly predict customer loyalty. Specifically, among
the dimension of tourism service quality, the most significant predictor
of customer loyalty is tangibility. This paper implies that five star
hotels in Jordan should also come forward and try their best to present
better tourism service quality to win back their customers- loyalty.
Abstract: Recent quasi-experimental evaluation of the Canadian Active Labour Market Policies (ALMP) by Human Resources and Skills Development Canada (HRSDC) has provided an opportunity to examine alternative methods to estimating the incremental effects of Employment Benefits and Support Measures (EBSMs) on program participants. The focus of this paper is to assess the efficiency and robustness of inverse probability weighting (IPW) relative to kernel matching (KM) in the estimation of program effects. To accomplish this objective, the authors compare pairs of 1,080 estimates, along with their associated standard errors, to assess which type of estimate is generally more efficient and robust. In the interest of practicality, the authorsalso document the computationaltime it took to produce the IPW and KM estimates, respectively.
Abstract: In the analysis of structures, the nonlinear effects due to large displacement, large rotation and materially-nonlinear are very important and must be considered for the reliable analysis. The non-linear fmite element analysis has potential as usable and reliable means for analyzing of civil structures with the availability of computer technology. In this research the large displacements and materially nonlinear behavior of shear wall is presented with developing of fmite element code using the standard Galerkin weighted residual formulation. Two-dimensional plane stress model was carried out to present the shear wall response. Total Lagangian formulation, which is computationally more effective, is used in the formulation of stiffness matrices and the Newton-Raphson method is applied for the solution of nonlinear transient equations. The details of the program formulation are highlighted and the results of the analyses are presented, along with a comparison of the response of the structure with Ansys software results. The presented model in this paper can be developed for nonlinear analysis of civil engineering structures with different material behavior and complicated geometry.
Abstract: The development of many measurement and inspection systems of products based on real-time image processing can not be carried out totally in a laboratory due to the size or the temperature of the manufactured products. Those systems must be developed in successive phases. Firstly, the system is installed in the production line with only an operational service to acquire images of the products and other complementary signals. Next, a recording service of the image and signals must be developed and integrated in the system. Only after a large set of images of products is available, the development of the real-time image processing algorithms for measurement or inspection of the products can be accomplished under realistic conditions. Finally, the recording service is turned off or eliminated and the system operates only with the real-time services for the acquisition and processing of the images. This article presents a systematic performance evaluation of the image compression algorithms currently available to implement a real-time recording service. The results allow establishing a trade off between the reduction or compression of the image size and the CPU time required to get that compression level.
Abstract: Human computer interaction has progressed
considerably from the traditional modes of interaction. Vision based
interfaces are a revolutionary technology, allowing interaction
through human actions, gestures. Researchers have developed
numerous accurate techniques, however, with an exception to few
these techniques are not evaluated using standard HCI techniques. In
this paper we present a comprehensive framework to address this
issue. Our evaluation of a computer vision application shows that in
addition to the accuracy, it is vital to address human factors
Abstract: The three steps of the standard one-way nested grid
for a regional scale of the third generation WAve Model Cycle 4
(WAMC4) is scrutinized. The model application is enabled to solve
the energy balance equation on a coarse resolution grid in order to
produce boundary conditions for a smaller area by the nested grid
technique. In the present study, the model takes a full advantage of the
fine resolution of wind fields in space and time produced by the available
U.S. Navy Global Atmospheric Prediction System (NOGAPS)
model with 1 degree resolution. The nested grid application of the
model is developed in order to gradually increase the resolution from
the open ocean towards the South China Sea (SCS) and the Gulf of
Thailand (GoT) respectively. The model results were compared with
buoy observations at Ko Chang, Rayong and Huahin locations which
were obtained from the Seawatch project. In addition, the results were
also compared with Satun based weather station which was provided
from Department of Meteorology, Thailand. The data collected from
this station presented the significant wave height (Hs) reached 12.85
m. The results indicated that the tendency of the Hs from the model
in the spherical coordinate propagation with deep water condition in
the fine grid domain agreed well with the Hs from the observations.
Abstract: Since the 1940s, many promising telepresence
research results have been obtained. However, telepresence
technology still has not reached industrial usage. As human
intelligence is necessary for successful execution of most manual
assembly tasks, the ability of the human is hindered in some cases,
such as the assembly of heavy parts of small/medium lots or
prototypes. In such a case of manual assembly, the help of industrial
robots is mandatory. The telepresence technology can be considered
as a solution for performing assembly tasks, where the human
intelligence and haptic sense are needed to identify and minimize the
errors during an assembly process and a robot is needed to carry
heavy parts. In this paper, preliminary steps to integrate the
telepresence technology into industrial robot systems are introduced.
The system described here combines both, the human haptic sense
and the industrial robot capability to perform a manual assembly task
remotely using a force feedback joystick. Mapping between the
joystick-s Degrees of Freedom (DOF) and the robot-s ones are
introduced. Simulation and experimental results are shown and future
work is discussed.
Abstract: The effect of shearing date on behaviors and performances of 20 pregnant Rahmani ewes was evaluated in four groups (5each). Ewes were shorn at 70, 100 and 130 days of pregnancy in the first three groups respectively, while the fourth group was maintained unshorn as a control. Some behavioral and physiological data related to ewes in addition, blood cortisol level were recorded. Results revealed a significant increase in the frequencies of comfort and eating behaviors, respiratory rate, pulse rate, lamb birth weight and blood cortisol level in early and mid pregnancy shorn ewes. Also, a slight increase in pregnancy period was observed for those ewes. On the other hand, social behaviors, and core temperature were not affected by shearing. These results conclude that prenatal shearing (early and mid-pregnancy) of ewes increases the frequencies of comfort and eating behaviors, and improves the survival rates of lambs by increasing their birth weights.
Abstract: The aim of this paper is to develop a new two dimensional time accurate Euler solver for shock tube applications. The solver was developed to study the performance of a newly built short-duration hypersonic test facility at Universiti Tenaga Nasional “UNITEN" in Malaysia. The facility has been designed, built, and commissioned for different values of diaphragm pressure ratios in order to get wide range of Mach number. The developed solver uses second order accurate cell-vertex finite volume spatial discretization and forth order accurate Runge-Kutta temporal integration and it is designed to simulate the flow process for similar driver/driven gases (e.g. air-air as working fluids). The solver is validated against analytical solution and experimental measurements in the high speed flow test facility. Further investigations were made on the flow process inside the shock tube by using the solver. The shock wave motion, reflection and interaction were investigated and their influence on the performance of the shock tube was determined. The results provide very good estimates for both shock speed and shock pressure obtained after diaphragm rupture. Also detailed information on the gasdynamic processes over the full length of the facility is available. The agreements obtained have been reasonable.
Abstract: Formative usability evaluation aims at finding
usability problems during the development process. The earlier these
problems are identified, the less expensive to fix they are. This paper
presents some preliminary results from a formative usability testing
of the 1st prototype developed for the ARiSE (Augmented Reality in
School Environments) project.
Abstract: In this paper, removal of chromium(VI) from aqueous
solution has been researched using reverse osmosis. The influence of
transmembrane pressure and feed concentration on permeate flux,
water recovery, permeate concentration, and salt rejection was
studied. The results showed that according to the variation of
transmembrane pressure and feed concentration, the permeate flux
and salt rejection were in the range 19.17 to 58.75 l/m2.min and
99.51 to 99.8 %, respectively. The highest permeate flux, 58.75
l/m2.min, and water recovery, 42.47 %, were obtained in the highest
pressure and the lowest feed concentration. On the other hand, the
lowest permeate concentration, 0.01 mg/l, and the highest salt
rejection, 99.8 %, were obtained in the highest pressure and the
lowest feed concentration.