Abstract: In this paper, we present a quantum statistical
mechanical formulation from our recently analytical expressions for
partial-wave transition matrix of a three-particle system. We report
the quantum reactive cross sections for three-body scattering
processes 1+(2,3)→1+(2,3) as well as recombination
1+(2,3)→1+(3,1) between one atom and a weakly-bound dimer. The
analytical expressions of three-particle transition matrices and their
corresponding cross-sections were obtained from the threedimensional
Faddeev equations subjected to the rank-two non-local
separable potentials of the generalized Yamaguchi form. The
equilibrium quantum statistical mechanical properties such partition
function and equation of state as well as non-equilibrium quantum
statistical properties such as transport cross-sections and their
corresponding transport collision integrals were formulated
analytically. This leads to obtain the transport properties, such as
viscosity and diffusion coefficient of a moderate dense gas.
Abstract: The end of the line controls of the finished products in
the automotive industry is important. The control that has been
conducted with the manual methods for the sliding doors tracks is not
sufficient and faulty products cannot be identified. As a result, the
customer has the faulty products. In the scope of this study, the
design criteria of the PLC integrated modular end of line control unit
has been examined, designed and manufactured to make the control
of the 10 different track profile to 2 different vehicles with an
objective to minimize the salvage costs by obtaining more sensitive,
certain and accurate measurement results. In the study that started
with literature and patent review, the design inputs have been
specified, the technical concept has been developed, computer
supported mechanic design, control system and automation design,
design review and design improvement have been made. Laser
analog sensors at high sensitivity, probes and modular blocks have
been used in the unit. The measurement has been conducted in the
system and it is observed that measurement results are more sensitive
than the previous methods that we use.
Abstract: Current transformers are an integral part of power
system because it provides a proportional safe amount of current for
protection and measurement applications. However, when the power
system experiences an abnormal situation leading to huge current
flow, then this huge current is proportionally injected to the
protection and metering circuit. Since the protection and metering
equipment’s are designed to withstand only certain amount of current
with respect to time, these high currents pose a risk to man and
equipment. Therefore, during such instances, the CT saturation
characteristics have a huge influence on the safety of both man and
equipment and on the reliability of the protection and metering
system. This paper shows the effect of burden on the Accuracy Limiting
factor/ Instrument security factor of current transformers and the
change in saturation characteristics of the CT’s. The response of the
CT to varying levels of overcurrent at different connected burden will
be captured using the data acquisition software LabVIEW. Analysis
is done on the real time data gathered using LabVIEW. Variation of
current transformer saturation characteristics with changes in burden
will be discussed.
Abstract: In internet of things (IoT) system, the communication
scheme with reliability and low power is required to connect a
terminal. Cooperative communication can achieve reliability and
lower power than multiple-input multiple-output (MIMO) system.
Cooperative communication increases the reliability with low
power, but decreases a throughput. It has a weak point that the
communication throughput is decreased. In this paper, a novel scheme
is proposed to increase the communication throughput. The novel
scheme is a transmission structure that increases transmission rate.
A decoding scheme according to the novel transmission structure is
proposed. Simulation results show that the proposed scheme increases
the throughput without bit error rate (BER) performance degradation.
Abstract: Carefully scheduling the operations of pumps can be
resulted to significant energy savings. Schedules can be defined
either implicit, in terms of other elements of the network such as tank
levels, or explicit by specifying the time during which each pump is
on/off. In this study, two new explicit representations based on timecontrolled
triggers were analyzed, where the maximum number of
pump switches was established beforehand, and the schedule may
contain fewer switches than the maximum. The optimal operation of
pumping stations was determined using a Jumping Particle Swarm
Optimization (JPSO) algorithm to achieve the minimum energy cost.
The model integrates JPSO optimizer and EPANET hydraulic
network solver. The optimal pump operation schedule of VanZyl
water distribution system was determined using the proposed model
and compared with those from Genetic and Ant Colony algorithms.
The results indicate that the proposed model utilizing the JPSO
algorithm is a versatile management model for the operation of realworld
water distribution system.
Abstract: The system of ordinary nonlinear differential
equations describing sliding velocity during impact with friction for a
three-dimensional rigid-multibody system is developed. No analytical
solutions have been obtained before for this highly nonlinear system.
Hence, a power series solution is proposed. Since the validity of this
solution is limited to its convergence zone, a suitable time step is
chosen and at the end of it a new series solution is constructed. For a
case study, the trajectory of the sliding velocity using the proposed
method is built using 6 time steps, which coincides with a Runge-
Kutta solution using 38 time steps.
Abstract: This paper describes how to dimension the electric
components of a 48V hybrid system considering real customer use.
Furthermore, it provides information about savings in energy and
CO2 emissions by a customer-tailored 48V hybrid. Based on measured customer profiles, the electric units such as the
electric motor and the energy storage are dimensioned. Furthermore,
the CO2 reduction potential in real customer use is determined
compared to conventional vehicles. Finally, investigations are carried
out to specify the topology design and preliminary considerations in
order to hybridize a conventional vehicle with a 48V hybrid system.
The emission model results from an empiric approach also taking into
account the effects of engine dynamics on emissions. We analyzed
transient engine emissions during representative customer driving
profiles and created emission meta models. The investigation showed
a significant difference in emissions when simulating realistic
customer driving profiles using the created verified meta models
compared to static approaches which are commonly used for vehicle
simulation.
Abstract: A sliding door system is used in commercial vehicles
and passenger cars to allow a larger unobstructed access to the
interior for loading and unloading. The movement of a sliding door
on vehicle body is ensured by mechanisms and tracks having special
cross-section which is manufactured by roll forming and stretch
bending process. There are three tracks and three mechanisms which
are called upper, central and lower on a sliding door system. There
are static requirements as strength on different directions, rigidity for
mechanisms, door drop off, door sag; dynamic requirements as high
energy slam opening-closing and durability requirement to validate
these products. In addition, there is a kinematic requirement to find
out force values from door handle during manual operating. In this
study, finite element analysis and physical test results which are
realized for sliding door systems will be shared comparatively.
Abstract: Nitrification is essential to biological processes
designed to remove ammonia and/or total nitrogen. It removes excess
nitrogenous compound in wastewater which could be very toxic to
the aquatic fauna or cause serious imbalance of such aquatic
ecosystem. Efficient nitrification is linked to an in-depth knowledge
of the structure and dynamics of the nitrifying community structure
within the wastewater treatment systems. In this study, molecular
technique was employed for characterizing the microbial structure of
activated sludge [ammonia oxidizing bacteria (AOB) and nitrite
oxidizing bacteria (NOB)] in a municipal wastewater treatment with
intention of linking it to the plant efficiency. PCR based phylogenetic
analysis was also carried out. The average operating and
environmental parameters as well as specific nitrification rate of plant
was investigated during the study. During the investigation the average temperature was 23±1.5oC.
Other operational parameters such as mixed liquor suspended solids
and chemical oxygen demand inversely correlated with ammonia
removal. The dissolved oxygen level in the plant was constantly
lower than the optimum (between 0.24 and 1.267 mg/l) during this
study. The plant was treating wastewater with influent ammonia
concentration of 31.69 and 24.47 mg/L. The influent flow rates
(ML/Day) was 96.81 during period. The dominant nitrifiers include:
Nitrosomonas spp. Nitrobacter spp. and Nitrospira spp. The AOB
had correlation with nitrification efficiency and temperature. This
study shows that the specific ammonia oxidizing rate and the specific
nitrate formation rates can serve as good indicator of the plant overall
nitrification performance.
Abstract: This paper aims to study the heat transfer and fluid
flow characteristics of nanofluids used in spray cooling systems. The
effect of spray height, type of nanofluids and concentration of
nanofluids are numerically investigated. Five different nanofluids
such as AgH2O, Al2O3, CuO, SiO2 and TiO2 with volume fraction
range of 0.5% to 2.5% are used. The results revealed that the heat
transfer performance decreases as spray height increases. It is found
that TiO2 has the highest transfer coefficient among other nanofluids.
In dilute spray conditions, low concentration of nanofluids is
observed to be more effective in heat removal in a spray cooling
system.
Abstract: This paper is aimed to study combustion characteristics
of low NOx burner using petroleum cokes as fuel. The petroleum coke,
which is produced through the oil refining process, is an attractive fuel
in terms of its high heating value and low price. But petroleum coke is
a challenging fuel because of its low volatile content, high sulfur and
nitrogen content, which give rise to undesirable emission
characteristics and low ignitability. Therefore, the research and
development regarding the petroleum coke burner is needed for
applying this industrial system. In this study, combustion and emission
characteristics of petroleum cokes burner are experimentally
investigated in an industrial steam boiler. The low NOx burner is
designed to control fuel and air mixing to achieve staged combustion,
which, in turn reduces both flame temperature and oxygen. Air
distribution ratio of triple staged air is optimized experimentally. The
result showed that NOx concentration is lowest when overfire air is
used, and the burner function at a fuel rich condition. That is, the
burner is operated at the equivalence ratio of 1.67 and overall
equivalence ratio including overfire air is kept 0.87.
Abstract: Although there has been a growing interest in the
hybrid free-space optical link and radio frequency FSO/RF
communication system, the current literature is limited to results
obtained in moderate or cold environment. In this paper, using a soft
switching approach, we investigate the effect of weather
inhomogeneities on the strength of turbulence hence the channel
refractive index under Qatar harsh environment and their influence
on the hybrid FSO/RF availability. In this approach, either FSO/RF
or simultaneous or none of them can be active. Based on soft
switching approach and a finite state Markov Chain (FSMC) process,
we model the channel fading for the two links and derive a
mathematical expression for the outage probability of the hybrid
system. Then, we evaluate the behavior of the hybrid FSO/RF under
hazy and harsh weather. Results show that the FSO/RF soft switching
renders the system outage probability less than that of each link
individually. A soft switching algorithm is being implemented on
FPGAs using Raptor code interfaced to the two terminals of a
1Gbps/100 Mbps FSO/RF hybrid system, the first being implemented
in the region. Experimental results are compared to the above
simulation results.
Abstract: Water resource systems modeling has constantly been
a challenge through history for human beings. As the innovative
methodological development is evolving alongside computer sciences
on one hand, researches are likely to confront more complex and
larger water resources systems due to new challenges regarding
increased water demands, climate change and human interventions,
socio-economic concerns, and environment protection and
sustainability. In this research, an automatic calibration scheme has
been applied on the Gilan’s large-scale water resource model using
mathematical programming. The water resource model’s calibration
is developed in order to attune unknown water return flows from
demand sites in the complex Sefidroud irrigation network and other
related areas. The calibration procedure is validated by comparing
several gauged river outflows from the system in the past with model
results. The calibration results are pleasantly reasonable presenting a
rational insight of the system. Subsequently, the unknown optimized
parameters were used in a basin-scale linear optimization model with
the ability to evaluate the system’s performance against a reduced
inflow scenario in future. Results showed an acceptable match
between predicted and observed outflows from the system at selected
hydrometric stations. Moreover, an efficient operating policy was
determined for Sefidroud dam leading to a minimum water shortage
in the reduced inflow scenario.
Abstract: Ecological systems are exposed and are influenced by
various natural and anthropogenic disturbances. They produce
various effects and states seeking response symmetry to a state of
global phase coherence or stability and balance of their food webs.
This research project addresses the development of a computational
methodology for modeling plankton food webs. The use of
algorithms to establish connections, the generation of representative
fuzzy multigraphs and application of technical analysis of complex
networks provide a set of tools for defining, analyzing and evaluating
community structure of coastal aquatic ecosystems, beyond the
estimate of possible external impacts to the networks. Thus, this
study aims to develop computational systems and data models to
assess how these ecological networks are structurally and
functionally organized, to analyze the types and degree of
compartmentalization and synchronization between oscillatory and
interconnected elements network and the influence of disturbances on
the overall pattern of rhythmicity of the system.
Abstract: Communicating users' needs, goals and problems help
designers and developers overcome challenges faced by end users.
Personas are used to represent end users’ needs. In our research,
creating personas allowed the following questions to be answered:
Who are the potential user groups? What do they want to achieve by
using the service? What are the problems that users face? What
should the service provide to them? To develop realistic personas, we
conducted a focus group discussion with undergraduate and graduate
students and also interviewed a university librarian. The personas
were created to help evaluating the Institutional Repository that is
based on the DSpace system. The profiles helped to communicate
users' needs, abilities, tasks, and problems, and the task scenarios
used in the heuristic evaluation were based on these personas. Four
personas resulted of a focus group discussion with undergraduate and
graduate students and from interviewing a university librarian. We
then used these personas to create focused task-scenarios for a
heuristic evaluation on the system interface to ensure that it met
users' needs, goals, problems and desires. In this paper, we present
the process that we used to create the personas that led to devise the
task scenarios used in the heuristic evaluation as a follow up study of
the DSpace university repository.
Abstract: Fiber Reinforced Polymer (FRP) is a composite material with exceptional properties that are capable to replace conventional steel reinforcement in reinforced and pre-stressed concrete structures. However, the main obstacle for their wide use in pre-stressed concrete application is the anchorage system. Due to the weakness of FRP in the transverse direction, the pre-stressing capacity of FRP bars are limited. This paper investigates the modification of the conventional wedge anchorage system to be used for stressing of FRP bars in pre-stressed applications. Epoxy adhesive material with glass FRP (GFRP) bars and conventional steel wedge were used in this paper. The GFRP bars are encased with epoxy at the anchor zone and the wedge system was used in pull-out test. The results showed a loading capacity of 47.6 kN which is 69% of the bar ultimate capacity. Additionally, nylon wedge was made with the same dimensions of the steel wedge and tested for GFRP bars without epoxy layer. The nylon wedge showed a loading capacity of 19.7 kN which is only 28.5% of the ultimate bar capacity.
Abstract: This study was carried out for an underground subway station at Seoul Metro, Korea. The optimal set-points of the ventilation control system are determined every 3 hours, then, the ventilation controller adjusts the ventilation fan speed according to the optimal set-point changes. Compared to manual ventilation system which is operated irrespective of the OAQ, the IDP-based ventilation control system saves 3.7% of the energy consumption. Compared to the fixed set-point controller which is operated irrespective of the IAQ diurnal variation, the IDP-based controller shows better performance with a 2% decrease in energy consumption, maintaining the comfortable IAQ range inside the station.
Abstract: This paper introduces a method to optimal design of a
hybrid Wind/Photovoltaic/Fuel cell generation system for a typical
domestic load that is not located near the electricity grid. In this
configuration the combination of a battery, an electrolyser, and a
hydrogen storage tank are used as the energy storage system. The aim
of this design is minimization of overall cost of generation scheme
over 20 years of operation. The Matlab/Simulink is applied for
choosing the appropriate structure and the optimization of system
sizing. A teaching learning based optimization is used to optimize the
cost function. An overall power management strategy is designed for
the proposed system to manage power flows among the different
energy sources and the storage unit in the system. The results have
been analyzed in terms of technical and economic. The simulation
results indicate that the proposed hybrid system would be a feasible
solution for stand-alone applications at remote locations.
Abstract: The primary objective of this work was to study the
effect of resin chemistry, pH and molarity of binding and elution
buffer on aggregate removal using Cation Exchange Chromatography
and find the optimum conditions which can give efficient aggregate
removal with minimum loss of yield. Four different resins were used
for carrying out the experiments: Fractogel EMD SO3
-(S), Fractogel EMD COO-(M), Capto SP ImpRes and S Ceramic HyperD. Runs
were carried out on the AKTA Avant system. Design of Experiments
(DOE) was used for analysis using the JMP software. The
dependence of the yield obtained using different resins on the
operating conditions was studied. Success has been achieved in
obtaining yield greater than 90% using Capto SP ImpRes and
Fractogel EMD COO-(M) resins. It has also been found that a change
in the operating conditions generally has different effects on the
yields obtained using different resins.
Abstract: The access to relevant information that is adapted to
user’s needs, preferences and environment is a challenge in many
applications running. That causes an appearance of context-aware
systems. To facilitate the development of this class of applications, it
is necessary that these applications share a common context
metamodel. In this article, we will present our context metamodel
that is defined using the OMG Meta Object facility (MOF).This
metamodel is based on the analysis and synthesis of context concepts
proposed in literature.