Abstract: The radius-of-curvature (ROC) defines the degree of
curvature along the centerline of a roadway whereby a travelling
vehicle must follow. Roadway designs must encompass ROC in
mitigating the cost of earthwork associated with construction while
also allowing vehicles to travel at maximum allowable design speeds.
Thus, a road will tend to follow natural topography where possible,
but curvature must also be optimized to permit fast, but safe vehicle
speeds. The more severe the curvature of the road, the slower the
permissible vehicle speed. For route planning, whether for urban
settings, emergency operations, or even parcel delivery, ROC is a
necessary attribute of road arcs for computing travel time.
It is extremely rare for a geo-spatial database to contain ROC. This
paper will present a procedure and mathematical algorithm to
calculate and assign ROC to a segment pair and/or polyline.
Abstract: The Beshar River is one of the most important aquatic ecosystems in the upstream of the Karun watershed in south of Iran which is affected by point and non point pollutant sources . This study was done in order to evaluate the effects of pollutants activities on the water quality of the Beshar river and its aquatic ecosystems. This river is approximately 190 km in length and situated at the geographical positions of 51° 20´ to 51° 48´ E and 30° 18´ to 30° 52´ N it is one of the most important aquatic ecosystems of Kohkiloye and Boyerahmad province in south-west Iran. In this research project, five study stations were selected to examine water pollution in the Beshar River systems. Human activity is now one of the most important factors affecting on hydrology and water quality of the Beshar river. Humans use large amounts of resources to sustain various standards of living, although measures of sustainability are highly variable depending on how sustainability is defined. The Beshar river ecosystems are particularly sensitive and vulnerable to human activities. Therefore, to determine the impact of human activities on the Beshar River, the most important water quality parameters such as pH, dissolve oxygen (DO), Biological Oxygen Demand (BOD5), Total Dissolve Solids (TDS), Nitrates (NO3-N) and Phosphates (PO4) were estimated at the five stations. As the results show, the most important pollution index parameters such as BOD5, NO3 and PO4 increase and DO and pH decrease according to human activities (P
Abstract: Nano fibers produced by electrospinning are of industrial and scientific attention due to their special characteristics such as long length, small diameter and high surface area. Applications of electrospun structures in nanotechnology are included tissue scaffolds, fibers for drug delivery, composite reinforcement, chemical sensing, enzyme immobilization, membrane-based filtration, protective clothing, catalysis, solar cells, electronic devices and others. Many polymer and ceramic precursor nano fibers have been successfully electrospun with diameters in the range from 1 nm to several microns. The process is complex so that fiber diameter is influenced by various material, design and operating parameters. The objective of this work is to apply genetic algorithm on the parameters of electrospinning which have the most significant effect on the nano fiber diameter to determine the optimum parameter values before doing experimental set up. Effective factors including initial polymer concentration, initial jet radius, electrical potential, relaxation time, initial elongation, viscosity and distance between nozzle and collector are considered to determine finest diameter which is selected by user.
Abstract: In the present study, computational fluid dynamics
(CFD) simulation has been executed to investigate the transition
boundaries of different flow patterns for moderately viscous oil-water
(viscosity ratio 107, density ratio 0.89 and interfacial tension of 0.032
N/m.) two-phase flow through a horizontal pipeline with internal
diameter and length of 0.025 m and 7.16 m respectively. Volume of
Fluid (VOF) approach including effect of surface tension has been
employed to predict the flow pattern. Geometry and meshing of the
present problem has been drawn using GAMBIT and ANSYS
FLUENT has been used for simulation. A total of 47037 quadrilateral
elements are chosen for the geometry of horizontal pipeline. The
computation has been performed by assuming unsteady flow,
immiscible liquid pair, constant liquid properties, co-axial flow and a
T-junction as entry section. The simulation correctly predicts the
transition boundaries of wavy stratified to stratified mixed flow.
Other transition boundaries are yet to be simulated. Simulated data
has been validated with our own experimental results.
Abstract: Mycophenolic acid (MPA) is a secondary metabolite
produced by Penicillium brevicompactum, which has antibiotic and
immunosuppressive properties. In this study, the first, mycophenolic
acid was produced in a fermentation process by Penicillium
brevicompactum MUCL 19011 in shake flask using a base medium.
The maximum MPA production, product yield and productivity of
process were 1.379 g/L, 18.6 mg/g glucose and 4.9 mg/L. h,
respectively. Also the glucose consumption, biomass and MPA
production profiles were investigated during batch cultivation.
Obtained results showed that MPA production starts approximately
after 180 hours and reaches to a maximum at 280 h. In the next step,
the effects of some various concentrations of enzymatically
hydrolyzed casein on MPA production were evaluated. Maximum
MPA production, product yield and productivity as 3.63 g/L, 49
mg/g glucose and 12.96 mg/L.h, respectively were obtained with
using 30 g/L enzymatically hydrolyzed casein in culture medium.
These values show an enhanced MPA production, product yield and
process productivity pr as 116.8%, 132.8% and 163.2%, respectively.
Abstract: Unmanned Aerial Vehicles (UAVs) have gained tremendous importance, in both Military and Civil, during first decade of this century. In a UAV, onboard computer (autopilot) autonomously controls the flight and navigation of the aircraft. Based on the aircraft role and flight envelope, basic to complex and sophisticated controllers are used to stabilize the aircraft flight parameters. These controllers constitute the autopilot system for UAVs. The autopilot systems, most commonly, provide lateral and longitudinal control through Proportional-Integral-Derivative (PID) controllers or Phase-lead or Lag Compensators. Various techniques are commonly used to ‘tune’ gains of these controllers. Some techniques used are, in-flight step-by-step tuning, software-in-loop or hardware-in-loop tuning methods. Subsequently, numerous in-flight tests are required to actually ‘fine-tune’ these gains. However, an optimization-based tuning of these PID controllers or compensators, as presented in this paper, can greatly minimize the requirement of in-flight ‘tuning’ and substantially reduce the risks and cost involved in flight-testing.
Abstract: The migration of a deformable drop in simple shear
flow at finite Reynolds numbers is investigated numerically by
solving the full Navier-Stokes equations using a finite
difference/front tracking method. The objectives of this study are to
examine the effectiveness of the present approach to predict the
migration of a drop in a shear flow and to investigate the behavior of
the drop migration with different drop sizes and non-unity viscosity
ratios. It is shown that the drop deformation depends strongly on the
capillary number, so that; the proper non-dimensional number for the
interfacial tension is the capillary number. The rate of migration
increased with increasing the drop radius. In other words, the
required time for drop migration to the centreline decreases. As the
viscosity ratio increases, the drop rotates more slowly and the
lubrication force becomes stronger. The increased lubrication force
makes it easier for the drop to migrate to the centre of the channel.
The migration velocity of the drop vanishes as the drop reaches the
centreline under viscosity ratio of one and non-unity viscosity ratios.
To validate the present calculations, some typical results are
compared with available experimental and theoretical data.
Abstract: This paper discusses a new heavy tailed distribution based data hiding into discrete cosine transform (DCT) coefficients of image, which provides statistical security as well as robustness against steganalysis attacks. Unlike other data hiding algorithms, the proposed technique does not introduce much effect in the stegoimage-s DCT coefficient probability plots, thus making the presence of hidden data statistically undetectable. In addition the proposed method does not compromise on hiding capacity. When compared to the generic block DCT based data-hiding scheme, our method found more robust against a variety of image manipulating attacks such as filtering, blurring, JPEG compression etc.
Abstract: The performance of ground to deep space optical
communication systems is degraded by distortion of the beam as it
propagates through the turbulent atmosphere. Turbulence causes
fluctuations in the intensity of the received signal which ultimately
affects the acquisition time required to acquire and locate the spaceborne
target using narrow laser beam. In this paper, performance of
free-space optical (FSO) communication system in atmospheric
turbulence has been analyzed in terms of acquisition time for
coherent and non-coherent modulation schemes. Numerical results
presented in graphical and tabular forms show that the acquisition
time increases with the increase in turbulence level. This is true for
both schemes. The BPSK has lowest acquisition time among all
schemes. In non-coherent schemes, M-PPM performs better than the
other schemes. With the increase in M, acquisition time becomes
lower, but at the cost of increase in system complexity.
Abstract: Dissolved gas analysis has been accepted as a sensitive, informative and reliable technique for incipient faults detection in power transformers and is widely used. In the last few years this method, which has been recommended by IEEE Power & Energy society, has been applied for fault detection in load tap changers. Regarding the critical role of load tap changers in electrical network and essential of catastrophic failures prevention, it is necessary to choose "condition based preventative maintenance strategy" which leads to reduction in costs, the number of unnecessary visits as well as the probability of interruptions and also increment in equipment reliability. In current work, considering the condition based preventative maintenance strategy, condition assessment of an Elin tap changer was carried out using dissolved gas analysis.
Abstract: Voice Over IP (VoIP) is a technology that could pass
the voice traffic and data packet form over an IP network. Network
can be used for intranet or Internet. Phone calls using VoIP has
advantages in terms of cheaper cost of PSTN phone to more than
half, because the cost is calculated by the cost of the global nature of
the Internet. Session Initiation Protocol (SIP) is a signaling protocol
at the application layer which serves to establish, modify, and
terminate a multimedia session involving one or more users. This SIP
signaling has SIP message in text form that is used for session
management by the SIP components, such as User Agent, Registrar,
Redirect Server, and Proxy Server. To build a SIP communication is
required SIP Express Router (SER) to be able to receive SIP
messages, for handling the basic functions of SIP messages.
Problems occur when the NAT through which affects the voice
communication will be blocked starting from the sound that is not
sent or one side of the sound are sent (half duplex). How that could
be used to penetrate NAT is to use a given mediaproxy random RTP
port to penetrate NAT.
Abstract: This paper describes a rapid prototyping (RP)
technology for forming a hydroxyapatite (HA) bone scaffold model.
The HA powder and a silica sol are mixed into bioceramic slurry form
under a suitable viscosity. The HA particles are embedded in the
solidified silica matrix to form green parts via a wide range of process
parameters after processing by selective laser sintering (SLS). The
results indicate that the proposed process was possible to fabricate
multilayers and hollow shell structure with brittle property but
sufficient integrity for handling prior to post-processing. The
fabricated bone scaffold models had a surface finish of 25
Abstract: In this paper, we study statistical multiplexing of VBR
video in ATM networks. ATM promises to provide high speed realtime
multi-point to central video transmission for telemedicine
applications in rural hospitals and in emergency medical services.
Video coders are known to produce variable bit rate (VBR) signals
and the effects of aggregating these VBR signals need to be
determined in order to design a telemedicine network infrastructure
capable of carrying these signals. We first model the VBR video
signal and simulate it using a generic continuous-data autoregressive
(AR) scheme. We carry out the queueing analysis by the Fluid
Approximation Model (FAM) and the Markov Modulated Poisson
Process (MMPP). The study has shown a trade off: multiplexing
VBR signals reduces burstiness and improves resource utilization,
however, the buffer size needs to be increased with an associated
economic cost. We also show that the MMPP model and the Fluid
Approximation model fit best, respectively, the cell region and the
burst region. Therefore, a hybrid MMPP and FAM completely
characterizes the overall performance of the ATM statistical
multiplexer. The ramifications of this technology are clear: speed,
reliability (lower loss rate and jitter), and increased capacity in video
transmission for telemedicine. With migration to full IP-based
networks still a long way to achieving both high speed and high
quality of service, the proposed ATM architecture will remain of
significant use for telemedicine.
Abstract: We present a hardware oriented method for real-time
measurements of object-s position in video. The targeted application
area is light spots used as references for robotic navigation. Different
algorithms for dynamic thresholding are explored in combination
with component labeling and Center Of Gravity (COG) for highest
possible precision versus Signal-to-Noise Ratio (SNR). This method
was developed with a low hardware cost in focus having only one
convolution operation required for preprocessing of data.
Abstract: This paper deals with infinite time horizon fuzzy Economic Order Quantity (EOQ) models for deteriorating items with
stock dependent demand rate and nonlinear holding costs by taking deterioration rate θ0 as a triangular fuzzy number (θ0 −δ 1, θ0, θ0 +δ 2), where 1 2 0 0
Abstract: Accurate software cost estimates are critical to both
developers and customers. They can be used for generating request
for proposals, contract negotiations, scheduling, monitoring and
control. The exact relationship between the attributes of the effort
estimation is difficult to establish. A neural network is good at
discovering relationships and pattern in the data. So, in this paper a
comparative analysis among existing Halstead Model, Walston-Felix
Model, Bailey-Basili Model, Doty Model and Neural Network
Based Model is performed. Neural Network has outperformed the
other considered models. Hence, we proposed Neural Network
system as a soft computing approach to model the effort estimation
of the software systems.
Abstract: Particle swarm optimization (PSO) technique is applied to design the water distribution pipeline network. A simulation-optimization model is formulated with the objective of minimizing cost and is applied to a benchmark water distribution system optimization problem. The benchmark problem taken for the application of PSO technique to optimize the pipe size of the water distribution network is New York City water supply system problem. The results from the analysis infer that PSO is a potential alternative optimization technique when compared to other heuristic techniques for optimal sizing of water distribution systems.
Abstract: Because of the requirement for low sulfur content of
fuel oils, it is necessary to develop alternative methods for desulfurization of heavy fuel oil. Due to the disadvantages of HDS
technologies such as costs, safety and green environment, new
methods have been developed. Among these methods is ultrasoundassisted
oxidative desulfurization. Using ultrasound-assisted
oxidative desulfurization, compounds such as benzothiophene and
dibenzothiophene can be oxidized. As an alternative method is sulfur
elimination of heavy fuel oil by using of activated carbon in a packed column in batch condition. The removal of sulfur compounds in this
case to reach about 99%. The most important property of activated carbon is ability of it for adsorption, which is due to high surface area
and pore volume of it.
Abstract: Many advanced Routing protocols for wireless sensor networks have been implemented for the effective routing of data. Energy awareness is an essential design issue and almost all of these routing protocols are considered as energy efficient and its ultimate objective is to maximize the whole network lifetime. However, the introductions of video and imaging sensors have posed additional challenges. Transmission of video and imaging data requires both energy and QoS aware routing in order to ensure efficient usage of the sensors and effective access to the gathered measurements. In this paper, the performance of the energy-aware QoS routing Protocol are analyzed in different performance metrics like average lifetime of a node, average delay per packet and network throughput. The parameters considered in this study are end-to-end delay, real time data generation/capture rates, packet drop probability and buffer size. The network throughput for realtime and non-realtime data was also has been analyzed. The simulation has been done in NS2 simulation environment and the simulation results were analyzed with respect to different metrics.
Abstract: A computer cluster is a group of tightly coupled
computers that work together closely so that in many respects they
can be viewed as though they are a single computer. The components
of a cluster are commonly, but not always, connected to each other
through fast local area networks. Clusters are usually deployed to
improve performance and/or availability over that provided by a
single computer, while typically being much more cost-effective than
single computers of comparable speed or availability. This paper
proposed the way to implement the Beowulf Cluster in order to
achieve high performance as well as high availability.