Abstract: The perfect operation of common Active Filters is depended on accuracy of identification system distortion. Also, using a suitable method in current injection and reactive power compensation, leads to increased filter performance. Due to this fact, this paper presents a method based on predictive current control theory in shunt active filter applications. The harmonics of the load current is identified by using o–d–q reference frame on load current and eliminating the DC part of d–q components. Then, the rest of these components deliver to predictive current controller as a Threephase reference current by using Park inverse transformation. System is modeled in discreet time domain. The proposed method has been tested using MATLAB model for a nonlinear load (with Total Harmonic Distortion=20%). The simulation results indicate that the proposed filter leads to flowing a sinusoidal current (THD=0.15%) through the source. In addition, the results show that the filter tracks the reference current accurately.
Abstract: Earthmoving operations are a major part of many
construction projects. Because of the complexity and fast-changing
environment of such operations, the planning and estimating are
crucial on both planning and operational levels. This paper presents
the framework ofa microscopic discrete-event simulation system for
modeling earthmoving operations and conducting productivity
estimations on an operational level.A prototype has been developed
to demonstrate the applicability of the proposed framework, and this
simulation system is presented via a case study based on an actual
earthmoving project. The case study shows that the proposed
simulation model is capable of evaluating alternative operating
strategies and resource utilization at a very detailed level.
Abstract: This paper and its companion (Part 2) deal with
modeling and optimization of two NP-hard problems in production
planning of flexible manufacturing system (FMS), part type selection
problem and loading problem. The part type selection problem and
the loading problem are strongly related and heavily influence the
system-s efficiency and productivity. The complexity of the problems
is harder when flexibilities of operations such as the possibility of
operation processed on alternative machines with alternative tools are
considered. These problems have been modeled and solved
simultaneously by using real coded genetic algorithms (RCGA)
which uses an array of real numbers as chromosome representation.
These real numbers can be converted into part type sequence and
machines that are used to process the part types. This first part of the
papers focuses on the modeling of the problems and discussing how
the novel chromosome representation can be applied to solve the
problems. The second part will discuss the effectiveness of the
RCGA to solve various test bed problems.
Abstract: Back-to-back static synchronous compensator (BtBSTATCOM) consists of two back-to-back voltage-source converters (VSC) with a common DC link in a substation. This configuration extends the capabilities of conventional STATCOM that bidirectional active power transfer from one bus to another is possible. In this paper, VSCs are designed in quasi multi-pulse form in which GTOs are triggered only once per cycle in PSCAD/EMTDC. The design details of VSCs as well as gate switching circuits and controllers are fully represented. Regulation modes of BtBSTATCOM are verified and tested on a multi-machine power system through different simulation cases. The results presented in the form of typical time responses show that practical PI controllers are almost robust and stable in case of start-up, set-point change, and line faults.
Abstract: The paper presents an optimization study based on
genetic algorithms (GA-s) for a radio-frequency applicator used in
heating dielectric band products. The weakly coupled electro-thermal
problem is analyzed using 2D-FEM. The design variables in the
optimization process are: the voltage of a supplementary “guard"
electrode and six geometric parameters of the applicator. Two
objective functions are used: temperature uniformity and total active
power absorbed by the dielectric. Both mono-objective and multiobjective
formulations are implemented in GA optimization.
Abstract: Heart disease (HD) is a major cause of morbidity and mortality in the modern society. Medical diagnosis is an important but complicated task that should be performed accurately and efficiently and its automation would be very useful. All doctors are unfortunately not equally skilled in every sub specialty and they are in many places a scarce resource. A system for automated medical diagnosis would enhance medical care and reduce costs. In this paper, a new approach based on coactive neuro-fuzzy inference system (CANFIS) was presented for prediction of heart disease. The proposed CANFIS model combined the neural network adaptive capabilities and the fuzzy logic qualitative approach which is then integrated with genetic algorithm to diagnose the presence of the disease. The performances of the CANFIS model were evaluated in terms of training performances and classification accuracies and the results showed that the proposed CANFIS model has great potential in predicting the heart disease.
Abstract: Rotation or tilt present in an image capture by digital
means can be detected and corrected using Artificial Neural Network
(ANN) for application with a Face Recognition System (FRS). Principal
Component Analysis (PCA) features of faces at different angles
are used to train an ANN which detects the rotation for an input image
and corrected using a set of operations implemented using another
system based on ANN. The work also deals with the recognition
of human faces with features from the foreheads, eyes, nose and
mouths as decision support entities of the system configured using
a Generalized Feed Forward Artificial Neural Network (GFFANN).
These features are combined to provide a reinforced decision for
verification of a person-s identity despite illumination variations. The
complete system performing facial image rotation detection, correction
and recognition using re-enforced decision support provides a
success rate in the higher 90s.
Abstract: Owing to extensive use of hydrogen in refining or
petrochemical units, it is essential to manage hydrogen network in
order to make the most efficient utilization of hydrogen. On the other
hand, hydrogen is an important byproduct not properly used through
petrochemical complexes and mostly sent to the fuel system. A few
works have been reported in literature to improve hydrogen network
for petrochemical complexes. In this study a comprehensive analysis
is carried out on petrochemical units using a modified automated
targeting technique which is applied to determine the minimum
hydrogen consumption. Having applied the modified targeting
method in two petrochemical cases, the results showed a significant
reduction in required fresh hydrogen.
Abstract: Human amniotic membrane (HAM) is a useful
biological material for the reconstruction of damaged ocular surface.
The processing and preservation of HAM is critical to prevent the
patients undergoing amniotic membrane transplant (AMT) from cross
infections. For HAM preparation human placenta is obtained after an
elective cesarean delivery. Before collection, the donor is screened
for seronegativity of HCV, Hbs Ag, HIV and Syphilis. After
collection, placenta is washed in balanced salt solution (BSS) in
sterile environment. Amniotic membrane is then separated from the
placenta as well as chorion while keeping the preparation in BSS.
Scrapping of HAM is then carried out manually until all the debris is
removed and clear transparent membrane is acquired. Nitrocellulose
membrane filters are then placed on the stromal side of HAM, cut
around the edges with little membrane folded towards other side
making it easy to separate during surgery. HAM is finally stored in
solution of glycerine and Dulbecco-s Modified Eagle Medium
(DMEM) in 1:1 ratio containing antibiotics. The capped borosil vials
containing HAM are kept at -80°C until use. This vial is thawed to
room temperature and opened under sterile operation theatre
conditions at the time of surgery.
Abstract: Partial Discharge measurement is a very important
means of assessing the integrity of insulation systems in a High
Voltage apparatus. In compressed gas insulation systems, floating
particles can initiate partial discharge activities which adversely
affect the working of insulation. Partial Discharges below the
inception voltage also plays a crucial in damaging the integrity of
insulation over a period of time. This paper discusses the effect of
loose and fixed Copper and Nichrome wire particles on the PD
characteristics in SF6-N2 (10:90) gas mixtures at a pressure of
0.4MPa. The Partial Discharge statistical parameters and their
correlation to the observed results are discussed.
Abstract: In the present paper, the three-dimensional
temperature field of tool is determined during the machining and
compared with experimental work on C45 workpiece using carbide
cutting tool inserts. During the metal cutting operations, high
temperature is generated in the tool cutting edge which influence on
the rate of tool wear. Temperature is most important characteristic of
machining processes; since many parameters such as cutting speed,
surface quality and cutting forces depend on the temperature and high
temperatures can cause high mechanical stresses which lead to early
tool wear and reduce tool life. Therefore, considerable attention is
paid to determine tool temperatures. The experiments are carried out
for dry and orthogonal machining condition. The results show that
the increase of tool temperature depends on depth of cut and
especially cutting speed in high range of cutting conditions.
Abstract: Shot boundary detection is a fundamental step for the organization of large video data. In this paper, we propose a new method for video gradual shots detection and classification, using advantages of fractal analysis and AIS-based classifier. Proposed features are “vertical intercept" and “fractal dimension" of each frame of videos which are computed using Fourier transform coefficients. We also used a classifier based on Clonal Selection Algorithm. We have carried out our solution and assessed it according to the TRECVID2006 benchmark dataset.
Abstract: Classes on creativity, innovation, and entrepreneurship
are becoming quite popular at universities throughout the world.
However, it is not easy for business students to get involved to
innovative activities, especially patent application. The present study
investigated how to enhance business students- intention to participate
in innovative activities and which incentives universities should
consider. A 22-item research scale was used, and confirmatory factor
analysis was conducted to verify its reliability and validity. Multiple
regression and discriminant analyses were also conducted. The results
demonstrate the effect of growth-need strength on innovative behavior
and indicate that the theory of planned behavior can explain and
predict business students- intention to participate in innovative
activities. Additionally, the results suggest that applying our proposed
model in practice would effectively strengthen business students-
intentions to engage in innovative activities.
Abstract: Lean manufacturing is a production philosophy made
popular by Toyota Motor Corporation (TMC). It is globally known as
the Toyota Production System (TPS) and has the ultimate aim of
reducing cost by thoroughly eliminating wastes or muda. TPS
embraces the Just-in-time (JIT) manufacturing; achieving cost
reduction through lead time reduction. JIT manufacturing can be
achieved by implementing Pull system in the production.
Furthermore, TPS aims to improve productivity and creating
continuous flow in the production by arranging the machines and
processes in cellular configurations. This is called as Cellular
Manufacturing Systems (CMS). This paper studies on integrating the
CMS with the Pull system to establish a Big Island-Pull system
production for High Mix Low Volume (HMLV) products in an
automotive component industry. The paper will use the build-in JIT
system steps adapted from TMC to create the Pull system production
and also create a shojinka line which, according to takt time, has the
flexibility to adapt to demand changes simply by adding and taking
out manpower. This will lead to optimization in production.
Abstract: Wireless Sensor Network (WSN) comprises of sensor
nodes which are designed to sense the environment, transmit sensed
data back to the base station via multi-hop routing to reconstruct
physical phenomena. Since physical phenomena exists significant
overlaps between temporal redundancy and spatial redundancy, it is
necessary to use Redundancy Suppression Algorithms (RSA) for sensor
node to lower energy consumption by reducing the transmission
of redundancy. A conventional algorithm of RSAs is threshold-based
RSA, which sets threshold to suppress redundant data. Although
many temporal and spatial RSAs are proposed, temporal-spatial RSA
are seldom to be proposed because it is difficult to determine when
to utilize temporal or spatial RSAs. In this paper, we proposed a
novel temporal-spatial redundancy suppression algorithm, Codebookbase
Redundancy Suppression Mechanism (CRSM). CRSM adopts
vector quantization to generate a codebook, which is easily used to
implement temporal-spatial RSA. CRSM not only achieves power
saving and reliability for WSN, but also provides the predictability
of network lifetime. Simulation result shows that the network lifetime
of CRSM outperforms at least 23% of that of other RSAs.
Abstract: Recently research on human wayfinding has focused
mainly on mental representations rather than processes of
wayfinding. The objective of this paper is to demonstrate the
rationality behind applying multi-agent simulation paradigm to the
modeling of rescuer team wayfinding in order to develop
computational theory of perceptual wayfinding in crisis situations
using image schemata and affordances, which explains how people
find a specific destination in an unfamiliar building such as a
hospital. The hypothesis of this paper is that successful navigation is
possible if the agents are able to make the correct decision through
well-defined cues in critical cases, so the design of the building
signage is evaluated through the multi-agent-based simulation. In
addition, a special case of wayfinding in a building, finding one-s
way through three hospitals, is used to demonstrate the model.
Thereby, total rescue time for rescue operation during building fire is
computed. This paper discuses the computed rescue time for various
signage localization and provides experimental result for
optimization of building signage design. Therefore the most
appropriate signage design resulted in the shortest total rescue time in
various situations.
Abstract: This paper addresses a stock-cutting problem with rotation of items and without the guillotine cutting constraint. In order to solve the large-scale problem effectively and efficiently, we propose a simple but fast heuristic algorithm. It is shown that this heuristic outperforms the latest published algorithms for large-scale problem instances.
Abstract: The objective of this study was to investigate hydrogen production from alcohol wastewater by anaerobic sequencing batch reactor (ASBR) under thermophillic operation. The ASBR unit used in this study had a liquid holding volume of 4 L and was operated at 6 cycles per day. The seed sludge taken from an upflow anaerobic sludge blanket unit treating the same wastewater was boiled at 95 °C for 15 min before being fed to the ASBR unit. The ASBR system was operated at different COD loading rates at a thermophillic temperature (55 °C), and controlled pH of 5.5. When the system was operated under optimum conditions (providing maximum hydrogen production performance) at a feed COD of 60 000 mg/l, and a COD loading rate of 68 kg/m3 d, the produced gas contained 43 % H2 content in the produced gas. Moreover, the hydrogen yield and the specific hydrogen production rate (SHPR) were 130 ml H2/g COD removed and 2100 ml H2/l d, respectively.
Abstract: this study was carried out to investigate the changes in
quality parameters of rye bread packaged in different polymer films
during convection air-flow thermal treatment process. Whole loafs of
bread were placed in polymer pouches, which were sealed in reduced
pressure air ambiance, bread was thermally treated in
at temperature +(130; 140; and 150) ± 5 ºC within 40min, as long as
the core temperature of the samples have reached accordingly
+80±1 ºC. For bread packaging pouches were used: anti-fog
Mylar®OL12AF and thermo resistant combined polymer material.
Main quality parameters was analysed using standard methods:
temperature in bread core, bread crumb and crust firmness value,
starch granules volume and microflora. In the current research it was
proved, that polymer films significantly influence rye bread quality
parameters changes during thermal treatment. Thermo resistant
combined polymer material film could be recommendable for
packaged rye bread pasteurization, for maximal bread quality
parameter keeping.
Abstract: The automatic transmission (AT) is one of the most
important components of many automobile transmission systems. The
shift quality has a significant influence on the ride comfort of the
vehicle. During the AT shift process, the joint elements such as the
clutch and bands engage or disengage, linking sets of gears to create a
fixed gear ratio. Since these ratios differ between gears in a fixed gear
ratio transmission, the motion of the vehicle could change suddenly
during the shift process if the joint elements are engaged or disengaged
inappropriately, additionally impacting the entire transmission system
and increasing the temperature of connect elements.The objective was
to establish a system model for an AT powertrain using
Matlab/Simulink. This paper further analyses the effect of varying
hydraulic pressure and the associated impact on shift quality during
both engagment and disengagement of the joint elements, proving that
shift quality improvements could be achieved with appropriate
hydraulic pressure control.