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ISSN: 2308-1007
Published by NAUN
Year 2008
All papers of the journal were peer reviewed by two
independent reviewers. Acceptance was granted when both
reviewers' recommendations were positive.
Main
Page
Paper
Title, Authors, Abstract (Issue 1, Volume 2, 2008) |
Pages |
Environmental Awareness at the
Protected Area of Brilhante, Brazil
Martin S. Lassen, Thomas Panagopoulos
Abstract: Human occupation in rural
tropical watersheds has been contributing to a
steady degradation of water and other natural
resources. Agricultural expansion, deforestation and
a lack of sound sanitary equipments to treat
wastewater are conditions that threaten the
environmental quality of the Environmental
Protection Area of Brilhante (APA Brilhante),
located in Santa Catarina, South Brazil. The area,
being largely covered by native Atlantic Forest,
holds a number of natural springs, important for the
overall quality conservation and distribution of
water in rural parts of the municipality. In APA
Brilhante land use is permitted, but must be done in
accordance with the principles of sustainability. To
understand the socio-environmental conditions, the
possible threats to water quality and to highlight
the potential for alternative land uses, a field
survey was done based on interviewing families that
all lived inside or near the protected area. Results
show that degradation of soil and water combined
with pollution are the main concerns for the
population. If no alternative land use practices are
applied, the environmental conditions will continue
to degrade. Thus intelligent management, based on
socio-environmental understanding, education and
effective stakeholder collaboration is needed to
protect the landscape and secure the environmental
benefits that people can derive from working with
nature. The population requests information on how
to conserve water, soil and vegetation to protect
nature and continue farming for food production. For
this reason the study concludes that the Brilhante
community possesses great potential for the
adaptation of suitable land use practices. This will
help APA Brilhante to become a good example of
sustainable management for similar protected areas.
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1-8 |
Influence of Nitrogen and
Potassium on Yield, Fruit Quality and Mineral
Composition of Kiwifruit
Cecilia Pacheco, Fatima Calouro, Sara Vieira,
Francisco Santos, Nuno Neves, Fatima Curado, Justina
Franco, Sandra Rodrigues, Dulce Antunes
Abstract: Fertilization is one of the
main factors affecting the yield and quality of
kiwifruit (Actinidia deliciosa). Therefore, suitable
cultural practices, including fertilization, should
be studied in order to guarantee high production
levels and the maintenance of fruit quality. On the
other hand, physiological disorders during fruit
storage are common, leading to important losses of
marketable yield and can be strongly affected by the
mineral composition of fruits. This study lasted for
3 years (2004 to 2006) and experimental data was
obtained from a fertilizer trial arranged into
completely randomized blocks, with three
replications, installed in an orchard located in the
Portuguese Region of Bairrada (central Portugal).
This experiment was established in order to evaluate
the influence of nitrogen and potassium
fertilization on the yield and fruit quality of
kiwifruit cv. Hayward. Three levels of nitrogen (30,
60 and 90 kg ha-1N) and four levels of potassium (0,
45, 90 and 135 kg ha-1 K2O) were used, arranged into
12 experimental treatments. Since 2004, nitrogen and
potassium were applied annually. The total yield of
each plot was evaluated and fruits were graded into
six categories according to the weight and
deformations: fruits < 65g, [65 -75g], [75 -85g],
[85 -105g], ?105g and deformed fruits. After
harvest, fruits were stored in normal atmosphere at
0?C and 90-95% hygrometry conditions. After 50 days
of storage, one sample of each experimental
treatment consisting of 10 fruits from [85-105g]
size was taken to assess some quality parameters
namely, firmness of the pulp, titratable acidity,
and soluble solids content, at harvest. Other sample
of 16 fruits of each marketable fruit size
([65-75g], [75-85g], [85-105g] and ?105 g) was taken
from each plot and analysed for its mineral
composition (N, P, K, Ca, Mg, S, Na, Fe, Mn, Zn, Cu,
and B).The present paper reports experimental
results of a study with the main propose of
establishing the effect of nitrogen and potassium
fertilization on yield, fruit quality and fruit
mineral composition of Actinidia deliciosa ‘Hayward’
at 50 days after storage, corresponding to the
experimental period 2004 to 2006. Results showed a
significant mean effect of interaction NxK
fertilization on fruit yield. The annual mean
application of 60 kg ha-1 N, with the highest rate
of potassium, 135 kg ha-1 K2O, led to the highest
level of marketable fruit yield (19.1 tonnes ha-1).
The acidity and soluble solids contents of fruits
were not affected by nitrogen and potassium content
supply. However, both nutrients decreased the flesh
firmness. The interaction NxK fertilization
influenced fruit calcium concentration. The lowest
level of calcium was observed with 90 kg ha-1 N
associated with 90 kg ha-1 or 135 kg ha-1 K2O. Both
N/Ca and K/Ca ratios increased with nitrogen and
potassium supply.
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9-15 |
Ozone Layer Formation through
Corona Discharge utilizing Natural Phenomena
Jimit R. Sanghvi
Abstract: Here it has been tried to
explain the mechanism of ozone formation, which
would travel into the stratosphere where the odd
numbered oxygen particles(O3) has a longer lifetime,
thus basically serving to the formation, even though
gradually, of the ozone layer in the upper
atmosphere. An indepth analysis has been provided on
the basis of the current state of perception of
various atmospheric characteristics and phenomena
that can result or that can obstruct the formation
of ozone particles. A theory has been developed and
discussed for generation of climatic conditions to
induce various phenomena like thunderstorms,
lightning, etc.. The results of this phenomena is
been tried to explain with greater detail. Static
atmospheric conditions are discussed to try to
analyse the effects on the resultant theory of ozone
generation thus reducing or even curbing the global
warming by compensation of the depletion of ozone.
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16-24 |
Assessment of Development and
Regeneration Urban Projects: Cultural and
Operational Implications in Metropolization Context
Roberto De Lotto
Abstract: It has been worldwide
demonstrated that metropolization phenomenon is
changing in an indelible way the structure, the
shape, the livability and the environment of
contemporary cities. This phenomenon can not be
circumscribed in a specific national context but it
involves the urban sphere of the entire planet.
Moreover, the suburban growth and the connected
sprawl, have quite everywhere the same shape and
present the same problems: the most critical concern
the environmental issue, considered in an extensive
meaning, that involves both natural and anthropic
elements.
Considering the ecological approach the paper
explores cultural and operational implications of
assessment methodologies able to control and address
new developments to sustainability.
First the Metropolization phenomenon is analyzed
throughout general data and specific thematic
studies, considering the reasons of the birth and
diffusion of the suburban model and the related
critics; than the level of complexity that
integrated assessment principles involve is
connected to European Community proposals and to
ethical concepts capable to guide aware plans.
Finally a case study is presented with reference to
the Italian context and in particular to the city of
Pavia in which a research, developed by the author,
about renewal plans of urban dismissed area,
permitted to define a set of integrated criteria
that can support planners and designers in finding
sub-optimal revitalization solutions.
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25-34 |
Corrosion Analysis and Models
for some Composites Behavior in Saline Media
Alina Barbulescu, Lucica Orac
Abstract: Corrosion is one of the main
causes of metals degradation, which consists of
superficial and structural changes. It causes
damages and economic loss and can be prevented
mainly by choosing the materials with the best
properties for the working conditions.
When a material is introduced in an aqueous medium,
an electrochemical attack is produced. It can be
combined with other effects, as, for example, that
of cavitation.
In this context, we present the results of our
corrosion experiments on some composites materials
(simple and oil - impregnated) introduced in saline
water and in a cavitation field produced by
ultrasounds, in an experimental set - up especially
build for this purpose.
Also, mathematical models of absolute mass loss in
time and on surface for each material are given and
comparisons with other copper – base alloys are
done.
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35-44 |
Exergy Analysis Framework for
Underground Transportation Systems
Cornelia A. Bulucea, Daniel C. Cismaru, Doru A.
Nicola, Constantin Brandusa, Gheorghe Manolea,
Gabriela M. Cismaru
Abstract: The environmental problems
are mainly consequences from a too strong belief in
traditional engineering and economic growth as the
solution. An important human step against ignorance
should be to understand that the real world
processes involving energy and matter need to be
linked to the environmental engineering education,
design and operation. Energy systems involving
coversion chain processes are highly irreversible
and, consequently, they could have low exergy
efficiencies. This study aimed at examining an
underground railway train as a system where
different energy forms occur, so that the successive
energy conversion chain is emphasized and the energy
and exergy efficiencies, respectively, are compared.
Also, because at low speed the mechanical brake
can’t be avoid, among the environment issues, from
viewpoint of exergy efficiency, a special aspect is
represented by an abnormal but frequent situation of
train operation, concerning the unequal charge of
the traction induction motors. In this application
there are presented numerical simulations and
experimental data related to unequally charged
motors regime. The exergy analysis can help improve
and optimize the underground transportation system
design and operation, but also represents an
environmental engineering education example.
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45-55 |
Molecular Design, Synthesis and
Analysis of New Hydrophobic Seafoams with Augmented
Uptake Capacity
Rasha A. Azzam, Tarek M. Madkour
Abstract: The development of new
urethane seafoams to be used in the clean-up of oil
spills is the subject of this study. PU prepolymer
blends that are hydrophobic in nature are excellent
candidates for this technology. The hydrophobicity
of the prepolymer ensured maximum encapsulation of
the oil droplets within the foam cells during the
foaming of the polyurethane materials, which will
allow the sea area to be restored to its original
state without harming its surrounding habitat or
inhabitants. The advantage of the liquid state of
the prepolymer blends is to only solidify and foam
upon getting in contact with water, which will
facilitate its application using fire hoses mounted
on fireboats. In order to test the best materials
for this type of application, hundreds of organic
substrate candidates were tested using molecular
modeling techniques in order to evaluate their
miscibility with hydrocarbon oil. Elected organic
structures based on their higher miscibility with
oil will be synthesized in the laboratory and used
as the building blocks for the polyurethane
prepolymers. The more hydrophobic the prepolymer,
the more encapsulation of the oil droplets within
the foam cells during the foaming process is
expected to be. The organic substrate candidates of
various R groups, various diols of different types
and lengths, and various hard block sequence length
distribution have been modeled in order to evaluate
their miscibility with hydrocarbon oil. Prepolymer
structures of optimum miscibility with oil and
immiscibility with water identified as possible
chemical designs and prototypes for this type of
application were synthesized in the lab and
analyzed. The prepolymers were all analyzed using
FTIR and NMR spectroscopic techniques in order to
validate the results of the modeling investigation.
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56-65 |
Sustainable Urban Model through
Fuzzy Logic Weights
M. Roscia, D. Zaninelli, Gh. Lazaroiu
Abstract: The scope of this work is to
assign, by fuzzy logic, the weights to the different
indicators that can be taken in consideration in an
environmental impact, so to obtain a significant
homogeneity and objectivity. In this paper is
illustrated the calculation of the assigned weights
that uses a procedure based on fuzzy logic and to
define a model that allows us to estimate the
sustainability of a city. The environmental
indicator choice process for studying a specific
context results from a fundamental analysis of the
objectives, with the consideration that a good
indicator must be specific, sensitive, practical and
pertinent to the case under study and carefully
defined. The sustainable indicators are
characterized by a low degree of aggregation and a
high amount of information.
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66-72 |
Achieved Energy Assessment and
Modeling of Railway Transportation Systems with
Three Levels Converters
Daniel C. Cismaru, Doru A. Nicola, Cornelia A.
Bulucea, Gheorghe Manolea, Gabriela M. Cismaru
Abstract: This paper emphasizes a
number of sustainability-based concepts, such
achieved energy and exergy efficiency, related as
tools in order to describe, analyse and optimize
energy conversion in electric railway transportation
systems. For the sustainable railway vehicles, the
achieved energy assessment provides a basis for
exergy efficiency increasing, reducing both energy
losses and environmental damage. Further on,
achieved energy and exergy analysis more broadly can
help in optimizing designs and modeling decisions.
In this goal, the paper describes the mathematical
models and structural diagrams of the traction
induction motors, useful movement, three levels
voltage-source inverter and line-side converter used
on the locomotive fed from AC line. The overall
structural diagram construction for the principle
schemes corresponding to modern locomotives is also
presented. At the end are shown the simulated
waveforms of the three levels converters and the
running diagrams of a high speed train.
|
73-82 |
Input-Output-based Life Cycle
Energy Inventories and Modeling in Electric Trains
with Traction Induction Motors Fed from DC Line
Doru A. Nicola, Cornelia A. Bulucea, Daniel C.
Cismaru, Gheorghe Manolea, Gabriela M. Cismaru
Abstract: In this paper life-cycle
energy inventories and modeling of electric trains
with traction induction motors fed from d.c. line on
basis of input-output data study are presented. The
data– Life Cycle Analysis (LCA) relationship is
investigated, and the importance and role of data in
LCA is reviewed. There are taken into account the
electric trains with traction induction motors fed
from d.c. line, not simply in terms of technico-economical
growth, but also as achievements of the Sustainable
Development. The paper presents data regarding the
materials and energies in a lateral wall
manufacturing process and assess an exergetic
analysis on basis of mathematical models and
structural diagrams of the traction induction motor,
the voltage-source inverter and line-side converter
used on the trains fed from d.c. line. The overall
structural diagram construction for the principle
schemes corresponding to modern electric trains fed
from d.c. line is also presented. Through its
rational and meaningful approach, the Life Cycle
Energy Analysis, and particularly an Energy
Inventory will help improve and optimize the design,
manufacture, operation and final equipments
deconstruction of a transportation system.
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83-92 |
Morpho-Anatomical and
Physiological Effects of the Industrial Polluting
Agents from Moldavian Industrial Areas – Romania, on
Populus Tremula L
Maria Magdalena Zamfirache, Lacramioara Ivanescu,
Zenovia Olteanu, Ramona Crina Gales
Abstract: We have studied one specie
of wooden angiosperms from the areas next to the
industrial platforms in Borzesti (Bacau country) and
in Bicaz and Tasca (Neamt country). In the first
case, the noxious substances are mainly gaseous (sulphur
dioxide, chlorine, ammoniac), but also solid (carbon
black, soot); in the other two cases, the noxious
substances are mainly solid ones (lime or cement
powders prone to sedimentation). Our investigations
have focused on observations concerning the Populus
tremula L. specie, Salicaceae family, in various
phenophases, the state of the leaves surfaces and
physiological changes of the leaves under the
influence of the above-mentioned atmosphere
pollutants.
The polluting agents involved favor the installation
of a specific micro flora on the leaves (fungi and
algae), micro flora that affects their general
functions. The necrosis and the inducted foliar
chlorosis by polluting agents represent the clear
materialization of some profound physiological
modifications which disturb the photo-assimilating
structures, the medium content of water, dry
substance and assimilator pigments. In agreement
with the results of the experiences performed by
various researchers, using various concentrations of
several noxious substances on herbal and ligneous
species, whatever the type of noxious substance may
be, the cyto-histological changes in the leaves are
almost the same, phenotypising as chlorotic and
necrotic spots; in the later case, the structure of
all leaves is severely altered, which leads to the
degradation of the photo-assimilating structures,
and ultimately to the death of the entire plant.
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93-100 |
Intelligent Vehicle for
Passengers Transport - VISCET
Gheorghe Damian, Dumitru Tapu, Gheorghe Manolea,
Ileana Prejbeanu
Abstract: The publication presents the
results in a research grant [9] on the specific
equipment regarding the communication systems
specific to the rail intelligent vehicles. It is
presented the computing equipment designed in order
to provide a wide range of communication ways
between both equipment in the same car but also
between different coaches in the same convoy or
adjacent convoys.
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101-109 |
Paper
Title, Authors, Abstract (Issue 2, Volume 2, 2008) |
Pages |
Promoting Sustainability,
Heritage, and the Creative Economy τhrough Design
Annaliese Bischoff
Abstract: Through the use of design
studios conceptual design assistance was provided to
officials in a town in western Massachusetts to
promote sustainable design, heritage tourism, and
creative economy. This paper will highlight the
design process used and its resulting successes.
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111-120 |
Testing the Efficiency of the
European Carbon Futures Market using Event-Study
Methodology
Paul G. Miclaus, Radu Lupu, Sorin A. Dumitrescu,
Ana Bobirca
Abstract: The European Emissions
Trading Scheme (EU ETS) forms the centerpiece of EU
climate change policy. Within the new trading
system, the right to emit a particular amount of CO2
becomes a tradable commodity - called EU Allowances.
We test the AR(1)- GARCH(1,1) model on these young
markets and analyze the impact of National
Allocation Plans announcements on carbon prices, by
applying an event study methodology using daily
carbon futures returns. We find that markets are not
efficient as far as the correlation test is
concerned; nonetheless, the event study proves that,
even if past returns reacted to VER announcements,
the expectation building has been functioning
correctly since investors were able to predict the
market dynamics.
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121-128 |
Daylight, Solar Gains and
Overheating Studies in a Glazed Office Building
Hasim Altan, Ian Ward, Jitka Mohelnikova,
Frantisek Vajkay
Abstract: The Glazed envelopes
represent a possibility to use solar radiation for
reduction of energy consumption in buildings, which
is very important especially in regions with
temperate climatic conditions. Then again, glazed
facades are potential sources of unwanted
overheating and glare effects that cause indoor
discomfort and result in necessity for ventilation
and cooling services which again increase energy
consumption in buildings. The paper discusses the
analysis of an overheating issues occurred in a
naturally ventilated office building in Sheffield,
England. The building is designed with a south
facing fully glazed facade where solar energy is
utilized to provide cooling within the building. In
this study, indoor thermal conditions have been
measured in order to determine the overheating
periods during warm spring and summer months and the
findings of thermal discomfort levels are examined
on each floor level including open plan floor
spaces. The overheating periods are determined in a
duration where indoor air temperatures reach to 27?C
or above for more than two consecutive hours between
9am and 6pm, and the results of the analysis are
presented with a series of overheating studies. The
paper also reports the findings of monitoring
carried out for indoor environment in such an office
building with glazed facades during their summer
performance in temperate climatic conditions and
presents a comparison study with computer simulation
results, and discusses the further solutions
suggested for optimization of indoor comfort on the
basis of the investigations.
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129-138 |
Paper
Title, Authors, Abstract (Issue 3, Volume 2, 2008) |
Pages |
Energy Renovation of Office
Buildings in Greece – Potentials based on Case
Studies
Chris J. Koinakis, John K. Sakelaris
Abstract: The energy renovation and
the potentials of the energy savings in two office
buildings in Greece are examined in this paper,
within the frames of a renovation project for some
existing office buildings of the public sector. For
this reason energy audits and simulations were
performed. Significant energy savings were achieved
in both cases. The most effective measures proved to
be the energy efficient windows, the solar shading
and the natural ventilation strategies, the increase
of the insulation of the roof and the external
shell, the installation of highly efficient HVAC
systems and the upgrading of the artificial
lighting. The energy savings could decrease the
problems of the increased ventilation that proved to
be necessary in the lounge areas and also could
decrease the problems of high internal gains due to
the new extensive IT equipment. There are potentials
for adequate and flexible energy management if a
central master plan is implemented for a targeted
office building stock of the public sector in
Greece.
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139-148 |
Retrieving Integrated Water
Vapor Using AMSU-B Channels over Arctic Region
Mu Qiao, Jungang Miao
Abstract: In this paper we analyze the
influence of ice surface emissivity variation on
water vapor retrieval accuracy in Arctic region
using AMSU-B channels. The data of ice surface
emissivity in Arctic is agree with the result of
SEPOR-POLEX campaign, and six types of surfaces
including open water, nilas, pancake ice, flat
first-year ice, ridged first-year ice, multi-year
ice are analyzed respectively. Miao’s method and
improved version of Selbach are used to retrieve
Integrated Water Vapor (IWV) over each type of
surface respectively. Analyzing the IWV retrieved
with the two methods mentioned above, several
results can be obtained. First, the uncertainty of
retrieved IWV results from emissivity variance is
calculated over each kind of surface. Second,
retrieval algorithms over nilas and pancake need new
coefficients independently for their emissivities
are relatively larger than that of other surfaces.
Third, the IWV retrieved with improved version of
Selbach has less average bias but larger variance
than that with Miao’s method over five kinds of
surfaces except pancake ice.
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149-156 |
Channel Frequency Optimization
of Spaceborne Millimeter-Wave Radiometer for
Integrated Water Vapor Retrieval in Arctic Region
Haibo Zhao, Jungang Miao
Abstract: Water vapor information is
very important to understanding global climate
change, especially in the climatologically sensitive
polar region. In 1998, Miao proposed a method to
retrieve Integrated Water Vapor (IWV) content using
SSM/T2 channels over the ice covered polar region.
It has been proved to be effective in both Antarctic
and partial Arctic region by subsequent studies.
Unfortunately, with currently available millimeter
radiometer channel combinations, the retrievable IWV
content can not exceed 6kg/m2 using Method of Miao.
In this paper a new group of channel frequencies
around 183GHz are established for a future AMSU-B-like
radiometer, which is optimized for larger
retrievable IWV range in Arctic region. Results show
the retrievable IWV range has been expanded. The
atmosphere profiles being used in the optimization
process are in situ radiosonde data from IGRA,
suggesting the optimized channel combination is not
only workable in theory but also can be put into
practice for IWV retrieval in Arctic region.
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157-170 |
Paper
Title, Authors, Abstract (Issue 4, Volume 2, 2008) |
Pages |
Reclassifying Forest Type to a
New Forest Class based on Vegetation and Lithology
Characteristics using Geographic Information System
at Southern Johore, Malaysia
I. Mohd Hasmadi, S. Alias Mohd, K. Norizah
Abstract: Recently forest resources
management with regard to precision forestry concept
has been highlighted by forest managers, in order to
fulfill the demand on quality and reliable
information about forest area. According to the
Malaysian National Forestry Act 1984, forest is
classified into several types by general
classification which is based on vegetation types
broadly into dipterocarp forest, peat swamp forest
and mangrove forest. In applying precision forestry
approach, details classification and information are
required to render more accurate about managed
forest. Therefore, this study was carried out to
reclassify forest type to a new forest class based
on vegetation and lithology characteristic using GIS
technique. Ten new classes were successfully
generated and mapped by fusing layer of forest
vegetation types and lithology layer in Southern
Johore, namely Dipterocarp-Igneous, Dipterocarp-Sediment,
Dipterocarp-Alluvial, Peat-Igneous, Peat-Sediment,
Peat-Alluvial, Mangrove-Igneous, Mangrove-Sediment,
Mangrove-Alluvial and Limestone forest. In this
study, Syzygium spp. (19.83 %) was found in
abundance in two new forest classes; Dipterocarp-Igneous
and Dipterocarp-Sediment forest in Hulu Sedili
Permanent Forest Reserve (PFR). Beside that,
Elateriospermum tapos (9.92 %) and family of
Lauraceae (7.22 %) were found to be the most
dominant species in the Dipterocarp-Sediment forest,
while Macaranga spp. (11.21 %) and Elateriospermum
tapos (11.02 %) found dominant in Dipterocarp-Igneous
forest. From the sample plot, Dipterocarpaceae
family constituted only 3.09 % whereas the non-Dipterocarpaceae
family was 96.91 %. Hence, this study indicated that
there is variation in species dominancy at different
lithology of the same forest vegetation site.
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171-178 |
Comparison Study on Moving and
Transportation Performance of Transportation Modes
Wei Shi, Douwe Stapersma, Hugo T. Grimmelius
Abstract: The performance of a
transportation mode is introduced as the moving
(mechanical) performance and the transportation
performance, in this paper represented by the
mechanical index and the energy index. The paper
gives a mathematical deduction of the relationship
between the mechanical index and the energy index.
In the mechanical point of view, the range of the
mechanical index of different transportation modes
is calculated. On the basis of a non-dimensional ,
in both full load and typical load conditions, a
comparison of energy indexes of different
transportation modes is presented. Then the fuel
consumption and exhaust emissions of different
transportation modes are compared by means of a “ton
payload and distance specific factor” versus
“Square-Froude number” diagram. Furthermore, the
results of a case study demonstrate that low speed
operational strategies could improve the mechanical
efficiency and the energy efficiency of ships but
both the fuel consumption and emission would
deteriorate while sailing in part load condition or
with fluctuating speed.
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179-190 |
Constant Voltage Operation of
Self Excited Induction Generator using Optimization
Tools
Shelly Vadhera, K. S. Sandhu
Abstract: In this paper MATLAB/ TOOLS
such as Genetic Algorithm (GA), Pattern Search (PS)
and Quasi-Newton optimization tools have been used
to predict the behavior of self excited induction
generator (SEIG). GA is used to predict the value of
excitation capacitance to maintain the rated
terminal voltage for any value of load on the
machine terminals. Further analysis is extended to
predict the behavior of this generator with voltage
fluctuations across the load.
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191-198 |
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