Abstract: Power system stabilizers (PSS) are now routinely used in the industry to damp out power system oscillations. In this paper, particle swarm optimization (PSO) technique is applied to design a robust power system stabilizer (PSS). The design problem of the proposed controller is formulated as an optimization problem and PSO is employed to search for optimal controller parameters. By minimizing the time-domain based objective function, in which the deviation in the oscillatory rotor speed of the generator is involved; stability performance of the system is improved. The non-linear simulation results are presented under wide range of operating conditions; disturbances at different locations as well as for various fault clearing sequences to show the effectiveness and robustness of the proposed controller and their ability to provide efficient damping of low frequency oscillations. Further, all the simulations results are compared with a conventionally designed power system stabilizer to show the superiority of the proposed design approach.
Abstract: Aim of this work was to compare the efficacy of two
loading methods of proteins onto polymeric nanocarriers: adsorption
and encapsulation methods. Preliminary studies of protein loading
were done using Bovine Serum Albumin (BSA) as model protein.
Nanocarriers were prepared starting from polylactic co-glycolic acid
(PLGA) polymer; production methods used are two different variants
of emulsion evaporation method. Nanoparticles obtained were
analyzed in terms of dimensions by Dynamic Light Scattering and
Loading Efficiency of BSA by Bradford Assay. Loaded
nanoparticles were then submitted to in-vitro protein dissolution test
in order to study the effect of the delivery system on the release rate
of the protein.
Abstract: The MFCAV Riemann solver is practically used in many Lagrangian or ALE methods due to its merit of sharp shock profiles and rarefaction corners, though very often with numerical oscillations. By viewing it as a modification of the WWAM Riemann solver, we apply the MFCAV Riemann solver to the Lagrangian method recently developed by Maire. P. H et. al.. The numerical experiments show that the application is successful in that the shock profiles and rarefaction corners are sharpened compared with results obtained using other Riemann solvers. Though there are still numerical oscillations, they are within the range of the MFCAV applied in onther Lagrangian methods.
Abstract: The purpose of my research proposal is to
demonstrate that there is a relationship between EEG and
endometrial cancer.
The above relationship is based on an Aristotelian Syllogism;
since it is known that the 14-3-3 protein is related to the electrical
activity of the brain via control of the flow of Na+ and K+ ions and
since it is also known that many types of cancer are associated with
14-3-3 protein, it is possible that there is a relationship between EEG
and cancer. This research will be carried out by well-defined
diagnostic indicators, obtained via the EEG, using signal processing
procedures and pattern recognition tools such as neural networks in
order to recognize the endometrial cancer type. The current research
shall compare the findings from EEG and hysteroscopy performed on
women of a wide age range. Moreover, this practice could be
expanded to other types of cancer. The implementation of this
methodology will be completed with the creation of an ontology.
This ontology shall define the concepts existing in this research-s
domain and the relationships between them. It will represent the
types of relationships between hysteroscopy and EEG findings.
Abstract: In recent years Operational Transconductance Amplifier based high frequency integrated circuits, filters and systems have been widely investigated. The usefulness of OTAs over conventional OP-Amps in the design of both first order and second order active filters are well documented. This paper discusses some of the tunability issues using the Matlab/Simulink® software which are previously unreported for any commercial OTA. Using the simulation results two first order voltage controlled all pass filters with phase tuning capability are proposed.
Abstract: Improving the performance of the QCL through block diagram as well as mathematical models is the main scope of this paper. In order to enhance the performance of the underlined device, the mathematical model parameters are used in a reliable manner in such a way that the optimum behavior was achieved. These parameters play the central role in specifying the optical characteristics of the considered laser source. Moreover, it is important to have a large amount of radiated power, where increasing the amount of radiated power represents the main hopping process that can be predicted from the behavior of quantum laser devices. It was found that there is a good agreement between the calculated values from our mathematical model and those obtained with VisSim and experimental results. These demonstrate the strength of mplementation of both mathematical and block diagram models.
Abstract: Organizations face challenges supporting knowledge
workers due to their particular requirements for an environment
supportive of their self-guided learning activities which are important
to increase their productivity and to develop creative solutions to
non-routine problems. Face-to-face knowledge sharing remains
crucial in spite of a large number of knowledge management
instruments that aim at supporting a more impersonal transfer of
knowledge. This paper first describes the main criteria for a
conceptual and technical solution targeted at flexible management of
office space that aims at assigning those knowledge workers to the
same room that are most likely to thrive when being brought together
thus enhancing their knowledge work productivity. The paper
reflects on lessons learned from the implementation and operation of
such a solution in a project-focused organization and derives several
implications for future extensions that target to foster problem
solving, informal learning and personal development.
Abstract: The Institute of Product Development is dealing
with the development, design and dimensioning of micro components
and systems as a member of the Collaborative Research
Centre 499 “Design, Production and Quality Assurance of
Molded micro components made of Metallic and Ceramic Materials".
Because of technological restrictions in the miniaturization
of conventional manufacturing techniques, shape and
material deviations cannot be scaled down in the same proportion
as the micro parts, rendering components with relatively
wide tolerance fields. Systems that include such components
should be designed with this particularity in mind, often requiring
large clearance. On the end, the output of such systems
results variable and prone to dynamical instability. To save
production time and resources, every study of these effects
should happen early in the product development process and
base on computer simulation to avoid costly prototypes. A
suitable method is proposed here and exemplary applied to a
micro technology demonstrator developed by the CRC499. It
consists of a one stage planetary gear train in a sun-planet-ring
configuration, with input through the sun gear and output
through the carrier. The simulation procedure relies on ordinary
Multi Body Simulation methods and subsequently adds
other techniques to further investigate details of the system-s
behavior and to predict its response. The selection of the relevant
parameters and output functions followed the engineering
standards for regular sized gear trains. The first step is to
quantify the variability and to reveal the most critical points of
the system, performed through a whole-mechanism Sensitivity
Analysis. Due to the lack of previous knowledge about the system-s
behavior, different DOE methods involving small and
large amount of experiments were selected to perform the SA.
In this particular case the parameter space can be divided into
two well defined groups, one of them containing the gear-s profile
information and the other the components- spatial location.
This has been exploited to explore the different DOE techniques
more promptly. A reduced set of parameters is derived for
further investigation and to feed the final optimization process,
whether as optimization parameters or as external perturbation
collective. The 10 most relevant perturbation factors and 4 to 6
prospective variable parameters are considered in a new, simplified
model. All of the parameters are affected by the mentioned
production variability. The objective functions of interest
are based on scalar output-s variability measures, so the
problem becomes an optimization under robustness and reliability constrains. The study shows an initial step on the development
path of a method to design and optimize complex micro
mechanisms composed of wide tolerated elements accounting
for the robustness and reliability of the systems- output.
Abstract: Utilization of various sensors has made it possible to
extend capabilities of industrial robots. Among these are vision
sensors that are used for providing visual information to assist robot
controllers. This paper presents a method of integrating a vision
system and a simulation program with an industrial robot. The vision
system is employed to detect a target object and compute its location
in the robot environment. Then, the target object-s information is sent
to the robot controller via parallel communication port. The robot
controller uses the extracted object information and the simulation
program to control the robot arm for approaching, grasping and
relocating the object. This paper presents technical details of system
components and describes the methodology used for this integration.
It also provides a case study to prove the validity of the methodology
developed.
Abstract: In this study, the density dependent nonlinear reactiondiffusion
equation, which arises in the insect dispersal models, is
solved using the combined application of differential quadrature
method(DQM) and implicit Euler method. The polynomial based
DQM is used to discretize the spatial derivatives of the problem. The
resulting time-dependent nonlinear system of ordinary differential
equations(ODE-s) is solved by using implicit Euler method. The
computations are carried out for a Cauchy problem defined by a onedimensional
density dependent nonlinear reaction-diffusion equation
which has an exact solution. The DQM solution is found to be in a
very good agreement with the exact solution in terms of maximum
absolute error. The DQM solution exhibits superior accuracy at large
time levels tending to steady-state. Furthermore, using an implicit
method in the solution procedure leads to stable solutions and larger
time steps could be used.
Abstract: The literature has argued that firms based in industrial districts enjoy advantages for creating internal knowledge and absorbing external knowledge as a consequence of to the knowledge flows and spillovers that exist in the district. However, empirical evidence to show how belonging to an industrial district affects the business processes of creation and absorption of knowledge is scarce and, moreover, empirical research has not taken into account the influence of variations in the flows of knowledge circulating in each cluster. This study aims to extend empirical evidence on the effect that the stock of shared competencies in industrial districts has on the business processes of creation and absorption of knowledge, through data from an initial study on 952 firms and 35 industrial districts in Spain.
Abstract: This paper presents a research conducted to investigate the effect of mixing process on polypropylene (PP) modified bitumen mixed with well graded aggregate to form modified bituminous concrete mix. Two mode of mixing, namely dry and wet with different concentration of polymer polypropylene was used with 80/100 pen bitumen, to evaluate the bituminous concrete mix properties. Three percentages of polymer varying from 1-3% by the weight of bitumen was used in this study. Three mixes namely control mix, wet mix and dry mix were prepared. Optimum binder content was calculated considering Marshall Stability, flow, air voids and Marshall Quotient at different bitumen content varying from 4% - 6.5% for control, dry and wet mix. Engineering properties thus obtained at the calculated optimum bitumen content revealed that wet mixing process is advantageous in comparison to dry mixing as it increases the stiffness of the mixture with the increase in polymer content in bitumen. Stiffness value for wet mix increases with the increase in polymer content which is beneficial in terms of rutting. 1% PP dry mix also shows enhanced stiffness, with the air void content limited to 4%.The flow behaviour of dry mix doesn't indicate any major difference with the increase in polymer content revealing that polymer acting as an aggregate only without affecting the viscosity of the binder in the mix. Polypropylene (PP) when interacted with 80 pen base bitumen enhances its performance characteristics which were brought about by altered rheological properties of the modified bitumen. The decrease in flow with the increase in binder content reflects the increase in viscosity of binder which induces the plastic flow in the mix. Workability index indicates that wet mix were easy to compact up to desired void ratio in comparison to dry mix samples.
Abstract: "Bazaar" is a Persian word from the language of Iranians of 2500 years ago which has entered the languages of other countries. “Bazaar", the trading or marketing place with the architectural principles and concerns, was formed in Iran because of the long experience of marketing. This has become a valuable inheritance of Islamic ideological civilization and Iranian advanced architecture and a model of Islamic-marketing places with spectacular elements and parts, and the place for economical, social and cultural exchanges. “Bazaars" are found in cities of Iran and many Islamic countries in west of Asia and north of Africa. With the stable structure and function as a symbol of social values, this place has become the economic center and the illustration of stable architecture and advanced principles. “Bazaars" as the heart of Iranian cities economy with several major and minor rows of shops, in closed and open areas, along a fixed line or branches with beautiful arcs, patios, and frameworks are among the main national inheritance of Iran and one of the important Iranian architectural treasures because of its Iranian nobility.
Abstract: The purpose of this work was to study the effect of the
irrigation using waste water with various electric conductivities (T(0,92ds/m), EC3 (3ds/m) and EC6 (6ds/m) on three varieties of
quinoa cultivated in a field south of Morocco. The follow up of the evolution of the chemical and agronomic parameters throughout the
culture made it possible to determine the responses to the saline stress in arid conditions. Results showed that the salinity caused the
depression of plant-s height, and reduced the fresh and dry weight in
the different parts of the three varieties plants. The increase of the irrigation water EC didn-t affect the yield for the varieties. Thus,
quinoa resisted to salinity and proved a behavior of a facultative halophyte crop. In fact, the cultivation of this using treated wastewater is feasible especially in arid areas for a sustainable use of
water resources.
Abstract: This paper starts with a critical view of beautiful female images in the mass media being frequently generated by a stereotypical Korean concept of beauty. Several female beauty myths have evolved in Korea during the present decade. Nearly all of them have formed due to a deeply-ingrained androcentric ideology which objectifies women. Mass media causes the public to hold a distorted concept about female beauty. There is a huge gap between women in reality and representative women in the mass media. It is essential to have an unbiased perception of female images presented in the mass media. Due to cosmetic advertisements projecting contemporary images of female beauty to promote products, cosmetics images will be examined in regard to female beauty myths portrayed by the mass media. This paper will analyze features of female beauty myths in Korea and their intrinsic characteristics.
Abstract: The advancement in wireless technology with the wide
use of mobile devices have drawn the attention of the research and
technological communities towards wireless environments, such as
Wireless Local Area Networks (WLANs), Wireless Wide Area
Networks (WWANs), and mobile systems and ad-hoc networks.
Unfortunately, wired and wireless networks are expressively different
in terms of link reliability, bandwidth, and time of propagation delay
and by adapting new solutions for these enhanced
telecommunications, superior quality, efficiency, and opportunities
will be provided where wireless communications were otherwise
unfeasible. Some researchers define 4G as a significant improvement
of 3G, where current cellular network’s issues will be solved and data
transfer will play a more significant role. For others, 4G unifies
cellular and wireless local area networks, and introduces new routing
techniques, efficient solutions for sharing dedicated frequency bands,
and an increased mobility and bandwidth capacity. This paper
discusses the possible solutions and enhancements probabilities that
proposed to improve the performance of Transmission Control
Protocol (TCP) over different wireless networks and also the paper
investigated each approach in term of advantages and disadvantages.
Abstract: The effect of phosphorus supplementation of ammoniated rice straw was studied. The in vitro experiment was carried out following the first stage of Tilley and Terry method. The treatments consisting of four diets were A = 50% ammoniated rice straw + 50% concentrate (control), B = A + 0.2% Phosphor (P) supplement, C = A + 0.4% Phosphor (P) supplement, and D = A + 0.6% Phosphor (P) supplement of dry matter. Completely randomized design was used as the experimental design with differences among treatment means were examined using Duncan multiple range test. Variables measured were total bacterial and cellulolytic bacterial population, cellulolytic enzyme activity, ammonia (NH3) and volatile fatty acid (VFA) concentrations, as fermentability indicators and synthesized microbial protein, as well as degradability indicators including dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF) and cellulose. The results indicated that fermentability and degradability of diets consisting ammoniated rice straw with P supplementation were significantly higher than the control diet (P< 0.05). It is concluded that P supplementation is important to improve fermentability and degradability of rations containing ammoniated RS and concentrate. In terms of the most effective level of P supplementation occurred at a supplementation rate of 0.4% of dry matter.
Abstract: This paper focuses on reducing the power consumption
of wireless sensor networks. Therefore, a communication protocol
named LEACH (Low-Energy Adaptive Clustering Hierarchy) is modified.
We extend LEACHs stochastic cluster-head selection algorithm
by a modifying the probability of each node to become cluster-head
based on its required energy to transmit to the sink. We present
an efficient energy aware routing algorithm for the wireless sensor
networks. Our contribution consists in rotation selection of clusterheads
considering the remoteness of the nodes to the sink, and then,
the network nodes residual energy. This choice allows a best distribution
of the transmission energy in the network. The cluster-heads
selection algorithm is completely decentralized. Simulation results
show that the energy is significantly reduced compared with the
previous clustering based routing algorithm for the sensor networks.
Abstract: The practice of burying the solid waste under the ground is one of the waste disposal methods and dumping is known as an ultimate method in the fastest-growing cities like Rasht city in Iran. Some municipalities select the solid waste landfills without feasibility studies, programming, design and management plans. Therefore, several social and environmental impacts are created by these sites. In this study, the suitability of solid waste landfill in Rasht city, capital of Gilan Province is reviewed using Regional Screening Method (RSM), Geographic Information System (GIS) and Analytical Hierarchy Process (AHP). The results indicated that according to the suitability maps, the value of study site is midsuitable to suitable based on RSM and mid-suitable based on AHP.
Abstract: This paper features the proposed modeling and design
of a Robust Decentralized Periodic Output Feedback (RDPOF)
control technique for the active vibration control of smart flexible
multimodel Euler-Bernoulli cantilever beams for a multivariable
(MIMO) case by retaining the first 6 vibratory modes. The beam
structure is modeled in state space form using the concept of
piezoelectric theory, the Euler-Bernoulli beam theory and the Finite
Element Method (FEM) technique by dividing the beam into 4 finite
elements and placing the piezoelectric sensor / actuator at two finite
element locations (positions 2 and 4) as collocated pairs, i.e., as
surface mounted sensor / actuator, thus giving rise to a multivariable
model of the smart structure plant with two inputs and two outputs.
Five such multivariable models are obtained by varying the
dimensions (aspect ratios) of the aluminum beam, thus giving rise to
a multimodel of the smart structure system. Using model order
reduction technique, the reduced order model of the higher order
system is obtained based on dominant eigen value retention and the
method of Davison. RDPOF controllers are designed for the above 5
multivariable-multimodel plant. The closed loop responses with the
RDPOF feedback gain and the magnitudes of the control input are
observed and the performance of the proposed multimodel smart
structure system with the controller is evaluated for vibration control.