Abstract: In this paper, a new method is proposed to find the fuzzy optimal solution of fuzzy assignment problems by representing all the parameters as triangular fuzzy numbers. The advantages of the pro-posed method are also discussed. To illustrate the proposed method a fuzzy assignment problem is solved by using the proposed method and the obtained results are discussed. The proposed method is easy to understand and to apply for finding the fuzzy optimal solution of fuzzy assignment problems occurring in real life situations.
Abstract: Spray chilling using air-mist nozzles has received
much attention in the food processing industry because of the
benefits it has shown over forced air convection. These benefits
include an increase in the heat transfer coefficient and a reduction in
the water loss by the product during cooling. However, few studies
have simulated the heat transfer and aerodynamics phenomena of the
air-mist chilling process for optimal operating conditions. The study
provides insight into the optimal conditions for spray impaction, heat
transfer efficiency and control of surface flooding. A computational
fluid dynamics model using a two-phase flow composed of water
droplets injected with air is developed to simulate the air-mist
chilling of food products. The model takes into consideration
droplet-to-surface interaction, water-film accumulation and surface
runoff. The results of this study lead to a better understanding of the
heat transfer enhancement, water conservation, and to a clear
direction for the optimal design of air-mist chilling systems that can
be used in commercial applications in the food and meat processing
industries.
Abstract: Four phenylurea herbicides (isoproturon, chlortoluron, diuron and linuron) were dissolved in different water matrices in order to study their chemical degradation by using UV radiation, ozone and some advanced oxidation processes (UV/H2O2, O3/H2O2, Fenton reagent and the photo- Fenton system). The waters used were: ultra-pure water, a commercial mineral water, a groundwater and a surface water taken from a reservoir. Elimination levels were established for each herbicide and for several global quality parameters, and a kinetic study was performed in order to determine basic kinetic parameters of each reaction between the target phenylureas and these oxidizing systems.
Abstract: A major goal of any enterprise is to create a ratings
system of customer satisfaction, goods and services. It is obvious that
the company cannot change what is not measured. In order to get a
clearer picture of the preferences of the major consumer groups, this
stage should be based on extensive research, including a variety of
interviews and surveys. It is necessary to know the key benefits,
which determine customer satisfaction in the market segment, of the
properties of certain goods and services. It is important to estimate
the terms of these preferences from the viewpoint of the client. This
article discusses the importance of customer satisfaction, and ways of
assessing it.
Abstract: Heat pipes are two-phase heat transfer devices with
high effective thermal conductivity. Due to the high heat transport
capacity, heat exchanger with heat pipes has become much smaller
than traditional heat exchangers in handling high heat fluxes. With
the working fluid in a heat pipe, heat can be absorbed on the
evaporator region and transported to the condenser region where the
vapour condenses releasing the heat to the cooling media. Heat pipe
technology has found increasing applications in enhancing the
thermal performance of heat exchangers in microelectranics, energy
saving in HVAC systems for operating rooms,surgery centers, hotels,
cleanrooms etc, temperature regulation systems for the human body
and other industrial sectors. Development activity in heat pipe and
thermosyphon technology in asia in recent years is surveyed. Some
new results obtained in Australia and other countries are also
included.
Abstract: New regulations and standards for noise emission increasingly compel the automotive firms to make some improvements about decreasing the engine noise. Nowadays, the perforated reactive mufflers which have an effective damping capability are specifically used for this purpose. New designs should be analyzed with respect to both acoustics and back pressure. In this study, a reactive perforated muffler is investigated numerically and experimentally. For an acoustical analysis, the transmission loss which is independent of sound source of the present cross flow, the perforated muffler was analyzed by COMSOL. To be able to validate the numerical results, transmission loss was measured experimentally. Back pressure was obtained based on the flow field analysis and was also compared with experimental results. Numerical results have an approximate error of 20% compared to experimental results.
Abstract: The aim of the present study was to investigate the
chemical and biological properties of local cowpea seed protein
cultivated in Gizan region. The results showed that the cowpea and
its products contain high level of protein (22.9-77.6%), high
carbohydrates (9.4-64.3%) and low fats (0.1-0.3%). The trypsin and
chymotrypsin activities were found to be 32.2 and 15.2 units,
respectively. These activities were not affected in both defatted and
protein concentrate whereas they were significantly reduced in
isolated protein and cooked samples. The phytate content of cooked
and concentrated cowpea samples varied from 0.25% -0.32%,
respectively. Tannin content was found to be 0.4% and 0.23% for
cooked and raw samples, respectively. The in vitro protein
digestibility was very high in cowpea seeds (75.04-78.76%). The
biological evaluation using rats showed that the group fed with
animal feed containing casein gain more weight than those fed with
that containing cowpea. However, the group fed with cooked cowpea
gain more weight than those fed with uncooked cowpea. On the
other hand, in vivo digestion showed high value (98.33%) among the
group consumed casein compared to other groups those consumed
cowpea contains feed. This could be attributed to low antinutritional
factors in casein contains feed compared to those of cowpea contains
feed because cooking significantly increased the digestion rate
(80.8% to 83.5%) of cowpea contains feed. Furthermore, the
biological evaluation was high (91.67%) of casein containing feed
compared to that of cowpea containing feed (80.83%-87.5%). The
net protein utilization (NPU) was higher (89.67%) in the group fed
with casein containing feed than that of cowpea containing feed
(56.33%-69.67%).
Abstract: The State of Rio de Janeiro, Brazil, will hold two important events in the nearby future. In 2014 it will have the final game of the Football World Cup, and in 2016 it will be holding the Olympic Games. Therefore, the public transportation system (mainly buses) is of a major concern to the Rio de Janeiro State authorities-. The main objective of this work is to compare the quality of service of the bus companies operating in the cities of ItaperunaandCampos, both cities situated in the state of Rio de Janeiro, Brazil. The outcome of thiscomparison, based on the opinion of the bus users, has shownthemdispleased with the quality of the service provided by the bus companies operating in both cities. It is urgent the need to find possible practical alternatives to minimize the consequences of the main problems detected in this work. With these practical alternatives available, we will be able to offer to the Rio de Janeiro State authorities- suggestions about possible solutions to the main problems identified in this survey, as well as the time of implantation and costs of these solutions.
Abstract: The flow field over a flat roof model building has been numerically investigated in order to determine threedimensional CFD guidelines for the calculation of the turbulent flow over a structure immersed in an atmospheric boundary layer. To this purpose, a complete validation campaign has been performed through a systematic comparison of numerical simulations with wind tunnel experimental data. Wind tunnel measurements and numerical predictions have been compared for five different vertical positions, respectively from the upstream leading edge to the downstream bottom edge of the analyzed model. Flow field characteristics in the neighborhood of the building model have been numerically investigated, allowing a quantification of the capabilities of the CFD code to predict the flow separation and the extension of the recirculation regions. The proposed calculations have allowed the development of a preliminary procedure to be used as guidance in selecting the appropriate grid configuration and corresponding turbulence model for the prediction of the flow field over a three-dimensional roof architecture dominated by flow separation.
Abstract: All climate models agree that the temperature in
Greece will increase in the range of 1° to 2°C by the year 2030 and
mean sea level in Mediterranean is expected to rise at the rate of 5
cm/decade. The aim of the present paper is the estimation of the
coastline displacement driven by the climate change and sea level
rise. In order to achieve that, all known statistical and non-statistical
computational methods are employed on some Greek coastal areas.
Furthermore, Kalman filtering techniques are for the first time
introduced, formulated and tested. Based on all the above, shoreline
change signals and noises are computed and an inter-comparison
between the different methods can be deduced to help evaluating
which method is most promising as far as the retrieve of shoreline
change rate is concerned.
Abstract: Principally, plants grown in soilless culture may be
attacked by the same pests and diseases as cultivated traditionally in
soil. The most destructive phytopathogens are fungi, such as
Phythium, Phytophthora and Fusarium, followed by viruses, bacteria
and nematodes. We investigated effect of carbon nanotube filters on
disease management of soilless culture. Tomato seedlings transplant
in plastic pots filled with a soilless media of vermiculite. The crop
irrigated and fertilized using a hydroponic nutrient solution. We used
carbon nanotube filters for nutrient solution disinfection. Our results
show that carbon nanotube filtration significantly reduces pathogens
on tomato plants. Fungal elimination (Fusarium oxysporum and
Pythium spp.) was usually successful at about 96 to 99.9% all over
the cultural season. It is seem that in tomato soilless culture,
nanofiltration constitutes a reliable method that allows control of the
development of diseases caused by pathogenic fungi
Abstract: This paper describes a novel approach for deriving
modules from protein-protein interaction networks, which combines
functional information with topological properties of the network.
This approach is based on weighted clustering coefficient, which
uses weights representing the functional similarities between the
proteins. These weights are calculated according to the semantic
similarity between the proteins, which is based on their Gene
Ontology terms. We recently proposed an algorithm for identification
of functional modules, called SWEMODE (Semantic WEights for
MODule Elucidation), that identifies dense sub-graphs containing
functionally similar proteins. The rational underlying this approach is
that each module can be reduced to a set of triangles (protein triplets
connected to each other). Here, we propose considering semantic
similarity weights of all triangle-forming edges between proteins. We
also apply varying semantic similarity thresholds between
neighbours of each node that are not neighbours to each other (and
hereby do not form a triangle), to derive new potential triangles to
include in module-defining procedure. The results show an
improvement of pure topological approach, in terms of number of
predicted modules that match known complexes.
Abstract: The winding hot-spot temperature is one of the most
critical parameters that affect the useful life of the power
transformers. The winding hot-spot temperature can be calculated as
function of the top-oil temperature that can estimated by using the
ambient temperature and transformer loading measured data. This
paper proposes the estimation of the top-oil temperature by using a
method based on Least Squares Support Vector Machines approach.
The estimated top-oil temperature is compared with measured data of
a power transformer in operation. The results are also compared with
methods based on the IEEE Standard C57.91-1995/2000 and
Artificial Neural Networks. It is shown that the Least Squares
Support Vector Machines approach presents better performance than
the methods based in the IEEE Standard C57.91-1995/2000 and
artificial neural networks.
Abstract: In this paper, the innovative intelligent fuzzy weighted
input estimation method (FWIEM) can be applied to the inverse heat
transfer conduction problem (IHCP) to estimate the unknown
time-varying heat flux efficiently as presented. The feasibility of this
method can be verified by adopting the temperature measurement
experiment. We would like to focus attention on the heat flux
estimation to three kinds of samples (Copper, Iron and Steel/AISI 304)
with the same 3mm thickness. The temperature measurements are then
regarded as the inputs into the FWIEM to estimate the heat flux. The
experiment results show that the proposed algorithm can estimate the
unknown time-varying heat flux on-line.
Abstract: This paper discusses the investigation of a wearable
textile monopole antenna on specific absorption rate (SAR) for bodycentric
wireless communication applications at 2.45 GHz. The
antenna is characterized on a realistic 8 x 8 x 8 mm3 resolution
truncated Hugo body model in CST Microwave Studio software. The
result exhibited that the simulated SAR values were reduced
significantly by 83.5% as the position of textile monopole was
varying between 0 mm and 15 mm away from the human upper arm.
A power absorption reduction of 52.2% was also noticed as the
distance of textile monopole increased.
Abstract: In this study four Holstein steers with rumen fistula
fed 7 kg of dry matter (DM) of diets differing in concentrate to
alfalfa hay ratios as 60:40, 70:30, 80:20, and 90:10 in a 4 × 4 latin
square design. The pH of the ruminal fluid was measured before
the morning feeding (0.0 h) to 8 h post feeding. In this study, a
two-layered feed-forward neural network trained by the
Levenberg-Marquardt algorithm was used for modelling of ruminal
pH. The input variables of the network were time, concentrate to
alfalfa hay ratios (C/F), non fiber carbohydrate (NFC) and neutral
detergent fiber (NDF). The output variable was the ruminal pH.
The modeling results showed that there was excellent agreement
between the experimental data and predicted values, with a high
determination coefficient (R2 >0.96). Therefore, we suggest using
these model-derived biological values to summarize continuously
recorded pH data.
Abstract: Organizational communication is an administrative
function crucial especially for executives in the implementation of
organizational and administrative functions. Executives spend a
significant part of their time on communicative activities. Doing his or her daily routine, arranging meeting schedules, speaking on the telephone, reading or replying to business correspondence, or
fulfilling the control functions within the organization, an executive typically engages in communication processes.
Efficient communication is the principal device for the adequate implementation of administrative and organizational activities. For
this purpose, management needs to specify the kind of
communication system to be set up and the kind of communication
devices to be used. Communication is vital for any organization.
In conventional offices, communication takes place within the hierarchical pyramid called the organizational structure, and is known as formal or informal communication. Formal communication
is the type that works in specified structures within the organizational rules and towards the organizational goals. Informal communication, on the other hand, is the unofficial type taking place among staff as
face-to-face or telephone interaction.
Communication in virtual as well as conventional offices is
essential for obtaining the right information in administrative
activities and decision-making. Virtual communication technologies
increase the efficiency of communication especially in virtual teams.
Group communication is strengthened through an inter-group central
channel. Further, ease of information transmission makes it possible
to reach the information at the source, allowing efficient and correct decisions. Virtual offices can present as a whole the elements of information which conventional offices produce in different
environments.
At present, virtual work has become a reality with its pros and
cons, and will probably spread very rapidly in coming years, in line
with the growth in information technologies.
Abstract: In this paper, we study the formation control problem
for car-like mobile robots. A team of nonholonomic mobile robots navigate in a terrain with obstacles, while maintaining a desired
formation, using a leader-following strategy. A set of artificial potential field functions is proposed using the direct Lyapunov
method for the avoidance of obstacles and attraction to their designated targets. The effectiveness of the proposed control laws to verify the feasibility of the model is demonstrated through computer simulations
Abstract: Regenerative gas turbine engine cycle is presented that yields higher cycle efficiencies than simple cycle operating under the same conditions. The power output, efficiency and specific fuel consumption are simulated with respect to operating conditions. The analytical formulae about the relation to determine the thermal efficiency are derived taking into account the effected operation conditions (ambient temperature, compression ratio, regenerator effectiveness, compressor efficiency, turbine efficiency and turbine inlet temperature). Model calculations for a wide range of parameters are presented, as are comparisons with simple gas turbine cycle. The power output and thermal efficiency are found to be increasing with the regenerative effectiveness, and the compressor and turbine efficiencies. The efficiency increased with increase the compression ratio to 5, then efficiency decreased with increased compression ratio, but in simple cycle the thermal efficiency always increase with increased in compression ratio. The increased in ambient temperature caused decreased thermal efficiency, but the increased in turbine inlet temperature increase thermal efficiency.
Abstract: In the present study, the rate of NOx emission in a
combustion chamber working in conventional combustion and High
Temperature Air Combustion (HiTAC) system are examined using
CFD modeling. The effect of peak temperature, combustion air
temperature and oxygen concentration on NOx emission rate was
undertaken. Results show that in a fixed oxygen concentration,
increasing the preheated air temperature will increase the peak
temperature and NOx emission rate. In addition, it was observed that
the reduction of the oxygen concentration in the fixed preheated air
temperature decreases the peak temperature and NOx emission rate.
On the other hand, the results show that increase of preheated air
temperature at various oxygen concentrations increases the NOx
emission rate. However, the rate of increase in HiTAC conditions is
quite lower than the conventional combustion. The modeling results
show that the NOx emission rate in HiTAC combustion is 133% less
than that of the conventional combustion.