Abstract: This study investigates the performance of radial basis function networks (RBFN) in forecasting the monthly CO2 emissions of an electric power utility. We also propose a method for input variable selection. This method is based on identifying the general relationships between groups of input candidates and the output. The effect that each input has on the forecasting error is examined by removing all inputs except the variable to be investigated from its group, calculating the networks parameter and performing the forecast. Finally, the new forecasting error is compared with the reference model. Eight input variables were identified as the most relevant, which is significantly less than our reference model with 30 input variables. The simulation results demonstrate that the model with the 8 inputs selected using the method introduced in this study performs as accurate as the reference model, while also being the most parsimonious.
Abstract: This paper presents a new version of the SVM mixture algorithm initially proposed by Kwok for classification and regression problems. For both cases, a slight modification of the mixture model leads to a standard SVM training problem, to the existence of an exact solution and allows the direct use of well known decomposition and working set selection algorithms. Only the regression case is considered in this paper but classification has been addressed in a very similar way. This method has been successfully applied to engine pollutants emission modeling.
Abstract: Design for cost (DFC) is a method that reduces life
cycle cost (LCC) from the angle of designers. Multiple domain
features mapping (MDFM) methodology was given in DFC. Using
MDFM, we can use design features to estimate the LCC. From the
angle of DFC, the design features of family cars were obtained, such
as all dimensions, engine power and emission volume. At the
conceptual design stage, cars- LCC were estimated using back
propagation (BP) artificial neural networks (ANN) method and
case-based reasoning (CBR). Hamming space was used to measure the
similarity among cases in CBR method. Levenberg-Marquardt (LM)
algorithm and genetic algorithm (GA) were used in ANN. The
differences of LCC estimation model between CBR and artificial
neural networks (ANN) were provided. ANN and CBR separately
each method has its shortcomings. By combining ANN and CBR
improved results accuracy was obtained. Firstly, using ANN selected
some design features that affect LCC. Then using LCC estimation
results of ANN could raise the accuracy of LCC estimation in CBR
method. Thirdly, using ANN estimate LCC errors and correct errors in
CBR-s estimation results if the accuracy is not enough accurate.
Finally, economically family cars and sport utility vehicle (SUV) was
given as LCC estimation cases using this hybrid approach combining
ANN and CBR.
Abstract: The fundamental aim of extended expansion concept is
to achieve higher work done which in turn leads to higher thermal
efficiency. This concept is compatible with the application of
turbocharger and LHR engine. The Low Heat Rejection engine was
developed by coating the piston crown, cylinder head inside with
valves and cylinder liner with partially stabilized zirconia coating of
0.5 mm thickness. Extended expansion in diesel engines is termed as
Miller cycle in which the expansion ratio is increased by reducing the
compression ratio by modifying the inlet cam for late inlet valve
closing. The specific fuel consumption reduces to an appreciable level
and the thermal efficiency of the extended expansion turbocharged
LHR engine is improved.
In this work, a thermodynamic model was formulated and
developed to simulate the LHR based extended expansion
turbocharged direct injection diesel engine. It includes a gas flow
model, a heat transfer model, and a two zone combustion model. Gas
exchange model is modified by incorporating the Miller cycle, by
delaying inlet valve closing timing which had resulted in considerable
improvement in thermal efficiency of turbocharged LHR engines. The
heat transfer model, calculates the convective and radiative heat
transfer between the gas and wall by taking into account of the
combustion chamber surface temperature swings. Using the two-zone
combustion model, the combustion parameters and the chemical
equilibrium compositions were determined. The chemical equilibrium
compositions were used to calculate the Nitric oxide formation rate by
assuming a modified Zeldovich mechanism. The accuracy of this
model is scrutinized against actual test results from the engine. The
factors which affect thermal efficiency and exhaust emissions were
deduced and their influences were discussed. In the final analysis it is
seen that there is an excellent agreement in all of these evaluations.
Abstract: Efficient luminescence is reported for the first time in Eu2+ activated double Chlorides A2BCl4 (A=Alkali metal, B=Alkaline earth element). A simple wet-chemical preparation is described. Emission intensities are comparable to that of the commercial phosphor. Excitation covers near UV region. These phosphors may be useful for applications like solid state lighting, scintillation detectors and X-ray storage using photo-stimulable phosphors.
Abstract: Earthquakes are natural phenomena that occur with influence of a lot of parameters such as seismic activity, changing in the ground waters' motion, changing in the water-s temperature, etc. On the other hand, the radon gas concentrations in soil vary as nonlinear generally with earthquakes. Continuous measurement of the soil radon gas is very important for determination of characteristic of the seismic activity. The radon gas changes as continuous with strain occurring within the Earth-s surface during an earthquake and effects from the physical and the chemical processes such as soil structure, soil permeability, soil temperature, the barometric pressure, etc. Therefore, at the modeling researches are notsufficient to knowthe concentration ofradon gas. In this research, we determined relationships between radon emissions based on the environmental parameters and earthquakes occurring along the East Anatolian Fault Zone (EAFZ), Turkiye and predicted magnitudes of some earthquakes with the artificial neural network (ANN) model.
Abstract: This paper reviews the greenhouse gas emissions of prefabrication elements for residential development in Hong Kong. Prefabrication becomes a common practice in residential development in Hong Kong and is considered as a green approach. In Hong Kong, prefabrication took place at factories in Pearl River Delta. Although prefabrication reduces construction wastage, it might generate more greenhouse gas emission from transportation and manufacturing processes. This study attempts to measure the “cradle to site" greenhouse gas emission from prefabrication elements for a public housing development in Kai Tak area. The findings could help further reduction of greenhouse gas emissions through process improvement.
Abstract: Fossil fuel-firing power plants dominate electric
power generation in Taiwan, which are also the major contributor to
Green House gases (GHG). CO2 is the most important greenhouse
gas that cause global warming. This paper penetrates the relationship
between carbon trading for GHG reduction and power generation
expansion planning (GEP) problem for the electrical utility. The
Particle Swarm Optimization (PSO) Algorithm is presented to deal
with the generation expansion planning strategy of the utility with
independent power providers (IPPs). The utility has to take both the
IPPs- participation and environment impact into account when a new
generation unit is considering expanded from view of supply side.
Abstract: Gas flaring is one of the most GHG emitting sources in the oil and gas industries. It is also a major way for wasting such an energy that could be better utilized and even generates revenue. Minimize flaring is an effective approach for reducing GHG emissions and also conserving energy in flaring systems. Integrating waste and flared gases into the fuel gas networks (FGN) of refineries is an efficient tool. A fuel gas network collects fuel gases from various source streams and mixes them in an optimal manner, and supplies them to different fuel sinks such as furnaces, boilers, turbines, etc. In this article we use fuel gas network model proposed by Hasan et al. as a base model and modify some of its features and add constraints on emission pollution by gas flaring to reduce GHG emissions as possible. Results for a refinery case study showed that integration of flare gas stream with waste and natural gas streams to construct an optimal FGN can significantly reduce total annualized cost and flaring emissions.
Abstract: Benchmarking cleaner production performance is an
effective way of pollution control and emission reduction in coal-fired
power industry. A benchmarking method using two-stage
super-efficiency data envelopment analysis for coal-fired power plants
is proposed – firstly, to improve the cleaner production performance of
DEA-inefficient or weakly DEA-efficient plants, then to select the
benchmark from performance-improved power plants. An empirical
study is carried out with the survey data of 24 coal-fired power plants.
The result shows that in the first stage the performance of 16 plants is
DEA-efficient and that of 8 plants is relatively inefficient. The target
values for improving DEA-inefficient plants are acquired by
projection analysis. The efficient performance of 24 power plants and
the benchmarking plant is achieved in the second stage. The two-stage
benchmarking method is practical to select the optimal benchmark in
the cleaner production of coal-fired power industry and will
continuously improve plants- cleaner production performance.
Abstract: In recent years, global warming has become a
worldwide problem. The reduction of carbon dioxide emissions is a
top priority for many companies in the manufacturing industry. In the
automobile industry as well, the reduction of carbon dioxide emissions
is one of the most important issues. Technology to reduce the weight
of automotive parts improves the fuel economy of automobiles, and is
an important technology for reducing carbon dioxide. Also, even if
this weight reduction technology is applied to electric automobiles
rather than gasoline automobiles, reducing energy consumption
remains an important issue. Plastic processing of hollow pipes is one
important technology for realizing the weight reduction of automotive
parts. Ohashi et al. [1],[2] present an example of research on pipe
formation in which a process was carried out to enlarge a pipe
diameter using a lost core, achieving the suppression of wall thickness
reduction and greater pipe expansion than hydroforming.
In this study, we investigated a method to increase the wall
thickness of a pipe through pipe compression using planetary rolls.
The establishment of a technology whereby the wall thickness of a
pipe can be controlled without buckling the pipe is an important
technology for the weight reduction of products. Using the finite
element analysis method, we predicted that it would be possible to
increase the compression of an aluminum pipe with a 3mm wall
thickness by approximately 20%, and wall thickness by approximately
20% by pressing the hollow pipe with planetary rolls.
Abstract: Tea has several types of essential elements. Potassium,
magnesium and phosphorus are some examples of these elements.
Tea is widely used drink in Turkey, also some people puts a lemon
wedge to tea for different taste. In this study potassium, magnesium
and phosphorus contents after the hot water brewing of black and
green tea were determined by Optical Emission Spectroscopy (ICPOES).
Furthermore, how the lemon addition to teas affects the
concentrations of the potassium, magnesium and phosphorus
amount are investigated.
From the results, potassium, magnesium and phosphorus
concentrations are found as 3003.3, 597.1, 1167.2 ppm in black tea
and 3718.0, 3830.5, 376.4 ppm in green tea, respectively. After
lemon addition potassium, magnesium and phosphorus
concentrations are changed to 14930, 830.4, 1113.5 ppm in black tea
and 15460.0, 909.5, 1152.5 ppm in green tea, respectively.
It is seen that lemon addition affects some essential elements in
black and green Turkish teas.
Abstract: In order to avoid the potentially devastating
consequences of global warming and climate change, the carbon
dioxide “CO2" emissions caused due to anthropogenic activities must
be reduced considerably. This paper presents the first study
examining the feasibility of carbon sequestration in construction and
demolition “C&D" waste. Experiments were carried out in a self
fabricated Batch Reactor at 40ºC, relative humidity of 50-70%, and
flow rate of CO2 at 10L/min for 1 hour for water-to-solids ratio of 0.2
to 1.2. The effect of surface area was found by comparing the
theoretical extent of carbonation of two different sieve sizes (0.3mm
and 2.36mm) of C&D waste. A 38.44% of the theoretical extent of
carbonation equating to 4% CO2 sequestration extent was obtained
for C&D waste sample for 0.3mm sieve size. Qualitative,
quantitative and morphological analyses were done to validate
carbonate formation using X-ray diffraction “X.R.D.," thermal
gravimetric analysis “T.G.A., “X-Ray Fluorescence Spectroscopy
“X.R.F.," and scanning electron microscopy “S.E.M".
Abstract: Fractal analyses of successive event of explosion
earthquake and harmonic tremor recorded at Semeru volcano were
carried out to investigate the dynamical system regarding to their
generating mechanism. The explosive eruptions accompanied by
explosion earthquakes and following volcanic tremor which are
generated by continuous emission of volcanic ash. The fractal
dimension of successive event of explosion and harmonic tremor was
estimated by Critical Exponent Method (CEM). It was found that the
method yield a higher fractal dimension of explosion earthquakes and
gradually decrease during the occurrence of harmonic tremor, and can
be considerably as correlated complexity of the source mechanism
from the variance of fractal dimension.
Abstract: This paper presents the generation of bipolar square
wave pulses with characteristics that are suitable for liquid food
sterilization using a Cascaded H-bridge Multilevel Inverter (CHMI).
Bipolar square waves pulses have been reported as stable for a
longer time during the sterilization process with minimum heat
emission and increased efficiency. The CHMI allows the system to
produce bipolar square wave pulses and yielding high output voltage
without using a transformer while fulfilling the pulse requirements
for effective liquid food sterilization. This in turn can reduce power
consumption and cost of the overall liquid food sterilization system.
The simulation results have shown that pulses with peak output
voltage of 2.4 kV, pulse width of between 1 2s and 1 ms at
frequencies of 50 Hz and 100 Hz can be generated by a 7-level
CHMI. Results from the experimental set-up based on a 5-level
CHMI has indicated the potential of the proposed circuit in
producing bipolar square wave output pulses with peak values that
depends on the DC source level supplied to the CHMI modules,
pulse width of between 12.5 2s and 1 ms at frequencies of 50 Hz
and 100 Hz.
Abstract: A simple approach is demonstrated for growing large
scale, nearly vertically aligned ZnO nanowire arrays by thermal
oxidation method. To reveal effect of temperature on growth and
physical properties of the ZnO nanowires, gold coated zinc substrates
were annealed at 300 °C and 400 °C for 4 hours duration in air. Xray
diffraction patterns of annealed samples indicated a set of well
defined diffraction peaks, indexed to the wurtzite hexagonal phase of
ZnO. The scanning electron microscopy studies show formation of
ZnO nanowires having length of several microns and average of
diameter less than 500 nm. It is found that the areal density of wires
is relatively higher, when the annealing is carried out at higher
temperature i.e. at 400°C. From the field emission studies, the values
of the turn-on and threshold field, required to draw emission current
density of 10 μA/cm2 and 100 μA/cm2 are observed to be 1.2 V/μm
and 1.7 V/μm for the samples annealed at 300 °C and 2.9 V/μm and
3.7 V/μm for that annealed at 400 °C, respectively. The field
emission current stability, investigated over duration of more than 2
hours at the preset value of 1 μA, is found to be fairly good in both
cases. The simplicity of the synthesis route coupled with the
promising field emission properties offer unprecedented advantage
for the use of ZnO field emitters for high current density
applications.
Abstract: The environmental impact caused by industries is an issue that, in the last 20 years, has become very important in terms of society, economics and politics in Colombia. Particularly, the tannery process is extremely polluting because of uneffective treatments and regulations given to the dumping process and atmospheric emissions. Considering that, this investigation is intended to propose a management model based on the integration of Lean Supply Chain, Green Supply Chain, Cleaner Production and ISO 14001-2004, that prioritizes the strategic components of the organizations. As a result, a management model will be obtained and it will provide a strategic perspective through a systemic approach to the tanning process. This will be achieved through the use of Multicriteria Decision tools, along with Quality Function Deployment and Fuzzy Logic. The strategic approach that embraces the management model using the alignment of Lean Supply Chain, Green Supply Chain, Cleaner Production and ISO 14001-2004, is an integrated perspective that allows a gradual frame of the tactical and operative elements through the correct setting of the information flow, improving the decision making process. In that way, Small Medium Enterprises (SMEs) could improve their productivity, competitiveness and as an added value, the minimization of the environmental impact. This improvement is expected to be controlled through a Dashboard that helps the Organization measure its performance along the implementation of the model in its productive process.
Abstract: The value of emission factor was calculated in the
older type of Diesel engine operating on an engine testing bench and
then compared with the parameters monitored under similar
conditions when the EnviroxTM additive was applied. It has been
found out that the additive based on CeO2 nanoparticles reduces
emission of NOx. The dependencies of NOx emissions on reduced
torque, engine power and revolutions have been observed as well.
Abstract: Hydrogen sulfide (H2S) is a very toxic gas that is produced in very large quantities in the oil and gas industry. It cannot be flared to the atmosphere and Claus process based gas plants are used to recover the sulfur and convert the hydrogen to water. In this paper, we present optical characterization of an atmospheric pressure microwave plasma torch for H2S dissociation into hydrogen and sulfur. The torch is operated at 2.45 GHz with power up to 2 kW. Three different gases can simultaneously be injected in the plasma torch. Visual imaging and optical emission spectroscopy are used to characterize the plasma for varying gas flow rates and microwave power. The plasma length, emission spectra and temperature are presented. The obtained experimental results validate our earlier published simulation results of plasma torch.
Abstract: Combining energy efficiency with renewable energy
sources constitutes a key strategy for a sustainable future. The wind
power sector stands out as a fundamental element for the
achievement of the European renewable objectives and Portugal is no
exception to the increase of the wind energy for the electricity
generation. This work proposes an optimization model for the long
range electricity power planning in a system similar to the
Portuguese one, where the expected impacts of the increasing
installed wind power on the operating performance of thermal power
plants are taken into account. The main results indicate that the
increasing penetration of wind power in the electricity system will
have significant effects on the combined cycle gas power plants
operation and on the theoretically expected cost reduction and
environmental gains. This research demonstrated the need to address
the impact that energy sources with variable output may have, not
only on the short-term operational planning, but especially on the
medium to long range planning activities, in order to meet the
strategic objectives for the energy sector.