Abstract: An optimal control strategy based on simple model, a
single phase unity power factor boost converter is presented with an
evaluation of first order differential equations. This paper presents an
evaluation of single phase boost converter having power factor
correction. The simple discrete model of boost converter is formed
and optimal control is obtained, digital PI is adopted to adjust control
error. The method of instantaneous current control is proposed in this
paper for its good tracking performance of dynamic response. The
simulation and experimental results verified our design.
Abstract: Adsorption of proteins onto a solid surface is believed to be the initial and controlling step in biofouling. A better knowledge of the fouling process can be obtained by controlling the formation of the first protein layer at a solid surface. A number of methods have been investigated to inhibit adsorption of proteins. In this study, the adsorption kinetics of
Abstract: Fishing has always been an essential component of
the Polynesians- life. Fishhooks, mostly in pearl shell, found during
archaeological excavations are the artifacts related to this activity the
most numerous. Thanks to them, we try to reconstruct the ancient
techniques of resources exploitation, inside the lagoons and offshore.
They can also be used as chronological and cultural indicators. The
shapes and dimensions of these artifacts allow comparisons and
classifications used in both functional approach and chrono-cultural
perspective. Hence it is very important for the ethno-archaeologists
to dispose of reliable methods and standardized measurement of
these artifacts. Such a reliable objective and standardized method
have been previously proposed. But this method cannot be envisaged
manually because of the very important time required to measure
each fishhook manually and the quantity of fishhooks to measure
(many hundreds). We propose in this paper a detailed acquisition
protocol of fishhooks and an automation of every step of this method.
We also provide some experimental results obtained on the fishhooks
coming from three archaeological excavations sites.
Abstract: Slag sample from copper smelting operation in a
water jacket furnace from DRC plant was used. The study intends to
determine the effect of cooling in the extraction of base metals. The
cooling methods investigated were water quenching, air cooling and
furnace cooling. The latter cooling ways were compared to the
original as received slag. It was observed that, the cooling rate of the
slag affected the leaching of base metals as it changed the phase
distribution in the slag and the base metals distribution within the
phases. It was also found that fast cooling of slag prevented
crystallization and produced an amorphous phase that encloses the
base metals. The amorphous slags from the slag dumps were more
leachable in acidic medium (HNO3) which leached 46%Cu, 95% Co,
85% Zn, 92% Pb and 79% Fe with no selectivity at pH0, than in
basic medium (NH4OH). The leachability was vice versa for the
modified slags by quenching in water which leached 89%Cu with a
high selectivity as metal extractions are less than 1% for Co, Zn, Pb
and Fe at ambient temperature and pH12. For the crystallized slags,
leaching of base metals increased with the increase of temperature
from ambient temperature to 60°C and decreased at the higher
temperature of 80°C due to the evaporation of the ammonia solution
used for basic leaching, the total amounts of base metals that were
leached in slow cooled slags were very low compared to the
quenched slag samples.
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: A multi-agent type robot for disaster response in calamity scene is proposed in this paper. The proposed grouped rescue robots can perform cooperative reconnaissance and surveillance to achieve a given rescue mission. The multi-agent rescue of dual set robot consists of one master set and three slave units. The research for this rescue robot system is going to detect at harmful environment where human is unreachable, such as the building is infected with virus or the factory has hazardous liquid in effluent. As a dual set robot, with Bluetooth and communication network, the master set can connect with slave units and send information back to computer by wireless and monitor. Therefore, rescuer can be informed the real-time information in a calamity area. Furthermore, each slave robot is able to obstacle avoidance by ultrasonic sensors, and encodes distance and location by compass. The master robot can integrate every devices information to increase the efficiency of prospected and research unknown area.
Abstract: Although the Vietnamese catfish farming has grown
at very high rates in recent years, the industry has also faced many
problems affecting its sustainability. This paper studies the
perceptions of catfish farmers regarding risk and risk management
strategies in their production activities. Specifically, the study aims
to measure the consequences, likelihoods, and levels of risks as well
as the efficacy of risk management in Vietnamese catfish farming.
Data for the study were collected through a sample of 261 catfish
farmers in the Mekong Delta, Vietnam using a questionnaire survey
in 2008. Results show that, in general, price and production risks
were perceived as the most important risks. Farm management and
technical measures were perceived more effective than other kinds of
risk management strategies in risk reduction. Although price risks
were rated as important risks, price risk management strategies were
not perceived as important measures for risk mitigation. The results
of the study are discussed to provide implications for various
industry stakeholders, including policy makers, processors, advisors,
and developers of new risk management strategies.
Abstract: Nowadays the devices of night vision are widely used both for military and civil applications. The variety of night vision applications require a variety of the night vision devices designs. A web-based architecture of a software system for design assessment before producing of night vision devices is developed. The proposed architecture of the web-based system is based on the application of a mathematical model for designing of night vision devices. An algorithm with two components – for iterative design and for intelligent design is developed and integrated into system architecture. The iterative component suggests compatible modules combinations to choose from. The intelligent component provides compatible combinations of modules satisfying given user requirements to device parameters. The proposed web-based architecture of a system for design assessment of night vision devices is tested via a prototype of the system. The testing showed the applicability of both iterative and intelligent components of algorithm.
Abstract: The overall service performance of I/O intensive
system depends mainly on workload on its storage system. In
heterogeneous storage environment where storage elements from
different vendors with different capacity and performance are put
together, workload should be distributed according to storage
capability. This paper addresses data placement issue in short video
sharing website. Workload contributed by a video is estimated by the
number of views and life time span of existing videos in same
category. Experiment was conducted on 42,000 video titles in six
weeks. Result showed that the proposed algorithm distributed
workload and maintained balance better than round robin and random
algorithms.
Abstract: Urban planning, in particular on protected landscape
areas, demands an increasing role of public participation within the
frame of the efficiency of sustainable planning process. The
development of urban planning actions in Protected Landscape areas,
as Sintra-Cascais Natural Park, should perform a methodological
process that is structured over distinct sequential stages, providing
the development of a continuous, interactive, integrated and
participative planning. From the start of Malveira da Serra and Janes
Plan process, several public participation actions were promoted, in
order to involve the local agents, stakeholders and the population in
the decision of specific local key issues and define the appropriate
priorities within the goals and strategies previously settled. As a
result, public participation encouraged an innovative process that
guarantees the efficiency of sustainable urban planning and promotes
a sustainable new way of living in community.
Abstract: German electricity European options on futures using
Lévy processes for the underlying asset are examined. Implied
volatility evolution, under each of the considered models, is
discussed after calibrating for the Merton jump diffusion (MJD),
variance gamma (VG), normal inverse Gaussian (NIG), Carr, Geman,
Madan and Yor (CGMY) and the Black and Scholes (B&S) model.
Implied volatility is examined for the entire sample period, revealing
some curious features about market evolution, where data fitting
performances of the five models are compared. It is shown that
variance gamma processes provide relatively better results and that
implied volatility shows significant differences through time, having
increasingly evolved. Volatility changes for changed uncertainty, or
else, increasing futures prices and there is evidence for the need to
account for seasonality when modelling both electricity spot/futures
prices and volatility.
Abstract: The fluid flow and the properties of the hydraulic
fluid inside a torque converter are the main topics of interest in this
research. The primary goal is to investigate the applicability of
various viscous fluids inside the torque converter. The Taguchi
optimization method is adopted to analyse the fluid flow in a torque
converter from a design perspective. Calculations are conducted in
maximizing the pressure since greater the pressure, greater the torque
developed. Using the values of the S/N ratios obtained, graphs are
plotted. Computational Fluid Dynamics (CFD) analysis is also
conducted.
Abstract: The image segmentation method described in this
paper has been developed as a pre-processing stage to be used in
methodologies and tools for video/image indexing and retrieval by
content. This method solves the problem of whole objects extraction
from background and it produces images of single complete objects
from videos or photos. The extracted images are used for calculating
the object visual features necessary for both indexing and retrieval
processes.
The segmentation algorithm is based on the cooperation among an
optical flow evaluation method, edge detection and region growing
procedures. The optical flow estimator belongs to the class of
differential methods. It permits to detect motions ranging from a
fraction of a pixel to a few pixels per frame, achieving good results in
presence of noise without the need of a filtering pre-processing stage
and includes a specialised model for moving object detection.
The first task of the presented method exploits the cues from
motion analysis for moving areas detection. Objects and background
are then refined using respectively edge detection and seeded region
growing procedures. All the tasks are iteratively performed until
objects and background are completely resolved.
The method has been applied to a variety of indoor and outdoor
scenes where objects of different type and shape are represented on
variously textured background.
Abstract: one of the significant factors for improving the
accuracy of Land Surface Temperature (LST) retrieval is the correct
understanding of the directional anisotropy for thermal radiance. In
this paper, the multiple scattering effect between heterogeneous
non-isothermal surfaces is described rigorously according to the
concept of configuration factor, based on which a directional thermal
radiance model is built, and the directional radiant character for urban
canopy is analyzed. The model is applied to a simple urban canopy
with row structure to simulate the change of Directional Brightness
Temperature (DBT). The results show that the DBT is aggrandized
because of the multiple scattering effects, whereas the change range of
DBT is smoothed. The temperature difference, spatial distribution,
emissivity of the components can all lead to the change of DBT. The
“hot spot" phenomenon occurs when the proportion of high
temperature component in the vision field came to a head. On the other
hand, the “cool spot" phenomena occur when low temperature
proportion came to the head. The “spot" effect disappears only when
the proportion of every component keeps invariability. The model
built in this paper can be used for the study of directional effect on
emissivity, the LST retrieval over urban areas and the adjacency effect
of thermal remote sensing pixels.
Abstract: In recent years, new product development became more and more competitive and globalized, and the designing phase is critical for the product success. The concept of modularity can provide the necessary foundation for organizations to design products that can respond rapidly to market needs. The paper describes data structures and algorithms of intelligent Web-based system for modular design taking into account modules compatibility relationship and given design requirements. The system intelligence is realized by developed algorithms for choice of modules reflecting all system restrictions and requirements. The proposed data structure and algorithms are illustrated by case study of personal computer configuration. The applicability of the proposed approach is tested through a prototype of Web-based system.
Abstract: This paper aims to present a framework for the
organizational knowledge management, which seeks to deploy a
standardized structure for the integrated management of knowledge is
a common language based on domains, processes and global
indicators inspired by the COBIT framework 5 (ISACA, 2012),
which supports the integration of three technologies, enterprise
information architecture (EIA), the business process modeling (BPM)
and service-oriented architecture (SOA). The Gomak Framework is a
management platform that seeks to integrate the information
technology infrastructure, the structure of applications, information
infrastructure, and business logic and business model to support a
sound strategy of organizational knowledge management, low
process-based approach and concurrent engineering. Concurrent
engineering (CE) is a systematic approach to integrated product
development that respond to customer expectations, involving all
perspectives in parallel, from the beginning of the product life cycle.
(European Space Agency, 2000).
Abstract: In this paper a Public Key Cryptosystem is proposed
using the number theoretic transforms (NTT) over a ring of integer
modulo a composite number. The key agreement is similar to
ElGamal public key algorithm. The security of the system is based on
solution of multivariate linear congruence equations and discrete
logarithm problem. In the proposed cryptosystem only fixed numbers
of multiplications are carried out (constant complexity) and hence the
encryption and decryption can be done easily. At the same time, it is
very difficult to attack the cryptosystem, since the cipher text is a
sequence of integers which are interrelated. The system provides
authentication also. Using Mathematica version 5.0 the proposed
algorithm is justified with a numerical example.
Abstract: Due to the growing dynamic and complexity within
the market environment production enterprises in particular are faced
with new logistic challenges. Moreover, it is here in this dynamic
environment that the Logistic Operating Curve Theory also reaches
its limits as a method for describing the correlations between the
logistic objectives. In order to convert this theory into a method for
dynamically monitoring productions this paper will introduce
methods for reliably and quickly identifying structural changes
relevant to logistics.
Abstract: Exposure to ambient air pollution has been linked to a
number of health outcomes, starting from modest transient changes in
the respiratory tract and impaired pulmonary function, continuing to
restrict activity/reduce performance and to the increase emergency
rooms visits, hospital admissions or mortality. The increase of
allergenic symptoms has been associated with air contaminants such
as ozone, particulate matter, fungal spores and pollen.
Considering the potential relevance of crossed effects of nonbiological
pollutants and airborne pollens and fungal spores on
allergy worsening, the aim of this work was to evaluate the influence
of non-biological pollutants (O3 and PM10) and meteorological
parameters on the concentrations of pollen and fungal spores using
multiple linear regressions.
The data considered in this study were collected in Oporto which
is the second largest Portuguese city, located in the North. Daily
mean of O3, PM10, pollen and fungal spore concentrations,
temperature, relative humidity, precipitation, wind velocity, pollen
and fungal spore concentrations, for 2003, 2004 and 2005 were
considered. Results showed that the 90th percentile of the adjusted
coefficient of determination, P90 (R2aj), of the multiple regressions
varied from 0.613 to 0.916 for pollen and from 0.275 to 0.512 for
fungal spores. O3 and PM10 showed to have some influence on the
biological pollutants. Among the meteorological parameters
analysed, temperature was the one that most influenced the pollen
and fungal spores airborne concentrations. Relative humidity also
showed to have some influence on the fungal spore dispersion.
Nevertheless, the models for each pollen and fungal spore were
different depending on the analysed period, which means that the
correlations identified as statistically significant can not be, even so,
consistent enough.
Abstract: In this paper, we use Generalized Hamiltonian systems approach to synchronize a modified sixth-order Chua's circuit, which generates hyperchaotic dynamics. Synchronization is obtained between the master and slave dynamics with the slave being given by an observer. We apply this approach to transmit private information (analog and binary), while the encoding remains potentially secure.