Abstract: The Al-MoO3-P-CdTe-Al MOS sandwich structures
were fabricated by vacuum deposition method on cleaned glass
substrates. Capacitance versus voltage measurements were performed
at different frequencies and sweep rates of applied voltages for oxide
and semiconductor films of different thicknesses. In the negative
voltage region of the C-V curve a high differential capacitance of the
semiconductor was observed and at high frequencies (
Abstract: Using the pseudopotential technique the Sagdeev
potential equation has been derived in a plasma consisting of twotemperature
nonisothermal electrons, negatively charged dust grains
and warm positive ions. The study shows that the presence of
nonisothermal two-temperature electrons and charged dust grains
have significant effects on the excitation and structure of the ionacoustic
double layers in the model plasma under consideration. Only
compressive type double layer is obtained in the present plasma
model. The double layer solution has also been obtained by including
higher order nonlinearity and nonisothermality, which is shown to
modify the amplitude and deform the shape of the double layer.
Abstract: The turbocharger and turbocharging have been the
inherent component of diesel engines, so that critical parameters of
such engines, as BSFC (Brake Specific Fuel Consumption) or
thermal efficiency, fuel consumption, BMEP (Brake Mean Effective
Pressure), the power density output and emission level have been
improved extensively. In general, the turbocharger can be considered
as the most complex component of diesel engines, because it has
closely interrelated turbomachinery concepts of the turbines and the
compressors to thermodynamic fundamentals of internal combustion
engines and stress analysis of all components.
In this paper, a waste gate for a conventional single stage radial
turbine is investigated by consideration of turbochargers operation
constrains and engine operation conditions, without any detail
designs in the turbine and the compressor. Amount of opening waste
gate which extended between the ranges of full opened and closed
valve, is demonstrated by limiting compressor boost pressure ratio.
Obtaining of an optimum point by regard above mentioned items is
surveyed by three linked meanline modeling programs together
which consist of Turbomatch®, Compal®, Rital® madules in concepts
NREC® respectively.
Abstract: Ti6Al4V alloy is highly used in the automotive and
aerospace industry due to its good machining characteristics. Micro
EDM drilling is commonly used to drill micro hole on extremely hard
material with very high depth to diameter ratio. In this study, the
parameters of micro-electrical discharge machining (EDM) in drilling
of Ti6Al4V alloy is optimized for higher machining accuracy with
less hole-dilation and hole taper ratio. The micro-EDM machining
parameters includes, peak current and pulse on time. Fuzzy analysis
was developed to evaluate the machining accuracy. The analysis
shows that hole-dilation and hole-taper ratio are increased with the
increasing of peak current and pulse on time. However, the surface
quality deteriorates as the peak current and pulse on time increase.
The combination that gives the optimum result for hole dilation is
medium peak current and short pulse on time. Meanwhile, the
optimum result for hole taper ratio is low peak current and short pulse
on time.
Abstract: In this paper, we consider the vehicle routing problem
with mixed fleet of conventional and heterogenous electric vehicles
and time dependent charging costs, denoted VRP-HFCC, in which
a set of geographically scattered customers have to be served by a
mixed fleet of vehicles composed of a heterogenous fleet of Electric
Vehicles (EVs), having different battery capacities and operating
costs, and Conventional Vehicles (CVs). We include the possibility
of charging EVs in the available charging stations during the routes
in order to serve all customers. Each charging station offers charging
service with a known technology of chargers and time dependent
charging costs. Charging stations are also subject to operating time
windows constraints. EVs are not necessarily compatible with all
available charging technologies and a partial charging is allowed.
Intermittent charging at the depot is also allowed provided that
constraints related to the electricity grid are satisfied.
The objective is to minimize the number of employed vehicles and
then minimize the total travel and charging costs.
In this study, we present a Mixed Integer Programming Model and
develop a Charging Routing Heuristic and a Local Search Heuristic
based on the Inject-Eject routine with different insertion methods. All
heuristics are tested on real data instances.
Abstract: This research was conducted in the Mae Sot
Watershed where located in the Moei River Basin at the Upper
Salween River Basin in Tak Province, Thailand. The Mae Sot
Municipality is the largest urban area in Tak Province and situated in
the midstream of the Mae Sot Watershed. It usually faces flash flood
problem after heavy rain due to poor flood management has been
reported since economic rapidly bloom up in recent years. Its
catchment can be classified as ungauged basin with lack of rainfall
data and no any stream gaging station was reported. It was attached
by most severely flood events in 2013 as the worst studied case for
all those communities in this municipality. Moreover, other problems
are also faced in this watershed, such shortage water supply for
domestic consumption and agriculture utilizations including a
deterioration of water quality and landslide as well. The research
aimed to increase capability building and strengthening the
participation of those local community leaders and related agencies to
conduct better water management in urban area was started by mean
of the data collection and illustration of the appropriated application
of some short period rainfall forecasting model as they aim for better
flood relief plan and management through the hydrologic model
system and river analysis system programs. The authors intended to
apply the global rainfall data via the integrated data viewer (IDV)
program from the Unidata with the aim for rainfall forecasting in a
short period of 7-10 days in advance during rainy season instead of
real time record. The IDV product can be present in an advance
period of rainfall with time step of 3-6 hours was introduced to the
communities. The result can be used as input data to the hydrologic
modeling system model (HEC-HMS) for synthesizing flood
hydrographs and use for flood forecasting as well. The authors
applied the river analysis system model (HEC-RAS) to present flood
flow behaviors in the reach of the Mae Sot stream via the downtown
of the Mae Sot City as flood extents as the water surface level at
every cross-sectional profiles of the stream. Both models of HMS and
RAS were tested in 2013 with observed rainfall and inflow-outflow
data from the Mae Sot Dam. The result of HMS showed fit to the
observed data at the dam and applied at upstream boundary discharge
to RAS in order to simulate flood extents and tested in the field, and
the result found satisfying. The product of rainfall from IDV was fair
while compared with observed data. However, it is an appropriate
tool to use in the ungauged catchment to use with flood hydrograph
and river analysis models for future efficient flood relief plan and
management.
Abstract: Remote sensing plays a vital role in mapping of
resources and monitoring of environments of the earth. In the present
research study, mapping and monitoring of clay siltations occurred in
the Alkhod Dam of Muscat, Sultanate of Oman are carried out using
low-cost multispectral Landsat and ASTER data. The dam is
constructed across the Wadi Samail catchment for ground water
recharge. The occurrence and spatial distribution of siltations in the
dam are studied with five years of interval from the year 1987 of
construction to 2014. The deposits are mainly due to the clay, sand
and silt occurrences derived from the weathering rocks of ophiolite
sequences occurred in the Wadi Samail catchment. The occurrences
of clays are confirmed by minerals identification using ASTER
VNIR-SWIR spectral bands and Spectral Angle Mapper supervised
image processing method. The presence of clays and their spatial
distribution are verified in the field. The study recommends the
technique and the low-cost satellite data to similar region of the
world.
Abstract: This paper discusses the undesirable charge transfer
through the parasitic capacitances of the input transistors in a
multi-inputs voltage sense amplifier. Its intrinsic rail-to-rail voltage
transitions at the output nodes inevitably disturb the input sides
through the capacitive coupling between the outputs and inputs. Then,
it can possible degrade the stabilities of the reference voltage levels.
Moreover, it becomes more serious in multi-channel systems by
altering them for other channels, and so degrades the linearity of the
overall systems. In order to alleviate the internal node voltage
transition, the internal node stabilization techniques are proposed. It
achieves 45% and 40% improvements for node stabilization and input
referred disturbance, respectively.
Abstract: A computational fluid dynamics (CFD) model is
developed for rechargeable non-aqueous electrolyte lithium-air
batteries with a partial opening for oxygen supply to the cathode.
Multi-phase transport phenomena occurred in the battery are
considered, including dissolved lithium ions and oxygen gas in the
liquid electrolyte, solid-phase electron transfer in the porous
functional materials and liquid-phase charge transport in the
electrolyte. These transport processes are coupled with the
electrochemical reactions at the active surfaces, and effects of
discharge reaction-generated solid Li2O2 on the transport properties
and the electrochemical reaction rate are evaluated and implemented
in the model. The predicted results are discussed and analyzed in terms
of the spatial and transient distribution of various parameters, such as
local oxygen concentration, reaction rate, variable solid Li2O2 volume
fraction and porosity, as well as the effective diffusion coefficients. It
is found that the effect of the solid Li2O2 product deposited at the solid
active surfaces is significant on the transport phenomena and the
overall battery performance.
Abstract: Collection of storm water runoff and forcing it into the
groundwater is the need of the hour to sustain the ground water table.
However, the runoff entraps various types of sediments and other
floating objects whose removal are essential to avoid pollution of
ground water and blocking of pores of aquifer. However, it requires
regular cleaning and maintenance due to problem of clogging. To
evaluate the performance of filter system consisting of coarse sand
(CS), gravel (G) and pebble (P) layers, a laboratory experiment was
conducted in a rectangular column. The effect of variable thickness
of CS, G and P layers of the filtration unit of the recharge shaft on the
recharge rate and the sediment concentration of effluent water were
evaluated.
Medium sand (MS) of three particle sizes, viz. 0.150–0.300 mm
(T1), 0.300–0.425 mm (T2) and 0.425–0.600 mm of thickness 25 cm,
30 cm and 35 cm respectively in the top layer of the filter system and
having seven influent sediment concentrations of 250–3,000 mg/l
were used for experimental study. The performance was evaluated in
terms of recharge rates and clogging time. The results indicated that
100 % suspended solids were entrapped in the upper 10 cm layer of
MS, the recharge rates declined sharply for influent concentrations of
more than 1,000 mg/l. All treatments with higher thickness of MS
media indicated recharge rate slightly more than that of all treatment
with lower thickness of MS media respectively. The performance of
storm water infiltration systems was highly dependent on the
formation of a clogging layer at the filter. An empirical relationship
has been derived between recharge rates, inflow sediment load, size
of MS and thickness of MS with using MLR.
Abstract: Elastomeric dielectric material has recently become a
new alternative for actuator technology. The characteristics of
dielectric elastomers placed between two electrodes to withstand
large strain when electrodes are charged has attracted the attention of
many researcher to study this material for actuator technology. Thus,
in the past few years Danfoss Ventures A/S has established their own
dielectric electro-active polymer (DEAP), which was called
PolyPower.
The main objective of this work was to investigate the dynamic
characteristics for vibration control of a PolyPower actuator folded in
‘pull’ configuration. A range of experiments was carried out on the
folded actuator including passive (without electrical load) and active
(with electrical load) testing. For both categories static and dynamic
testing have been done to determine the behavior of folded DEAP
actuator.
Voltage-Strain experiments show that the DEAP folded actuator is
a non-linear system. It is also shown that the voltage supplied has no
effect on the natural frequency. Finally, varying AC voltage with
different amplitude and frequency shows the parameters that
influence the performance of DEAP folded actuator. As a result, the
actuator performance dominated by the frequency dependence of the
elastic response and was less influenced by dielectric properties.
Abstract: The progress of industry integrated circuits in recent
years has been pushed by continuous miniaturization of transistors.
With the reduction of dimensions of components at 0.1 micron and
below, new physical effects come into play as the standard simulators
of two dimensions (2D) do not consider. In fact the third dimension
comes into play because the transverse and longitudinal dimensions
of the components are of the same order of magnitude. To describe
the operation of such components with greater fidelity, we must
refine simulation tools and adapted to take into account these
phenomena. After an analytical study of the static characteristics of
the component, according to the different operating modes, a
numerical simulation is performed of field-effect transistor with
submicron gate MESFET GaInP. The influence of the dimensions of
the gate length is studied. The results are used to determine the
optimal geometric and physical parameters of the component for their
specific applications and uses.
Abstract: Solenoid operated electromagnetic control valve
(ECV) playing an important role for car’s air conditioning control
system. ECV is used in external variable displacement swash plate
type compressor and controls the entire air conditioning system by
means of a pulse width modulation (PWM) input signal supplying
from an external source (controller). Complete form of ECV contains
number of internal features like valve body, core, valve guide,
plunger, guide pin, plunger spring, bellows etc. While designing the
ECV; dimensions of different internal items must meet the standard
requirements as it is quite challenging. In this research paper,
especially the dimensioning of ECV body and its three pressure ports
through which the air/refrigerant passes are considered. Here internal
leakage test analysis of ECV body is being carried out from its
discharge port (Pd) to crankcase port (Pc) when the guide valve is
placed inside it. The experiments have made both in ordinary and
digital system using different assumptions and thereafter compare the
results.
Abstract: Water flow management is one of the most important
parts of river engineering. Non-uniformity distribution of rainfall and
various flow demand with unreasonable flow management will be
caused destroyed of river ecosystem. Then, it is very serious to
determine ecosystem flow requirement. In this paper, Flow duration
curve indices method which has hydrological based was used to
evaluate environmental flow in Gharasou River, Ardabil, Iran. Using
flow duration curve, Q90 and Q95 for different return periods were
calculated. Their magnitude were determined as 1-day, 3-day, 7-day
and 30 day. According the second method, hydraulic alteration
indices often had low and medium range. In order to maintain river at
an acceptable ecological condition, minimum daily discharge of
index Q95 is 0.7 m3.s-1.
Abstract: The rate of natural gas dissociation from the Coal
Matrix depends on depressurization of reservoir through removing of
the cleat water from the coal seam. These waters are similar to brine
and aged of very long years. For improving the connectivity through
fracking /fracturing, high pressure liquids are pumped off inside the
coal body. A significant quantity of accumulated water, a combined
mixture of cleat water and fracking fluids (back flow water) is
pumped out through gas well. In Queensland, Australia Coal Seam
Gas (CSG) industry is in booming state and estimated of 30,000 wells
would be active for CSG production forecasting life span of 30 years.
Integrated water management along with water softening programs is
practiced for subsequent treatment and later on discharge to nearby
surface water catchment. Water treatment is an important part of the
CSG industry. A case study on a CSG site and review on the test
results are discussed for assessing the Standards & Practices for
management of CSG by-product water and their subsequent disposal
activities. This study was directed toward (i) water management and
softening process in Spring Gully CSG field, (ii) Comparative
analysis on experimental study and standards and (iii) Disposal of the
treated water. This study also aimed for alternative usages and their
impact on vegetation, living species as well as long term effects.
Abstract: Batteries of electric vehicles (BEV) are becoming
more attractive with the advancement of new battery technologies
and promotion of electric vehicles. BEV batteries are recharged on
board vehicles using either the grid (G2V for Grid to Vehicle) or
renewable energies in a stand-alone application (H2V for Home to
Vehicle). This paper deals with the modeling, sizing and control of a
photovoltaic stand-alone application that can charge the BEV at
home. The modeling approach and developed mathematical models
describing the system components are detailed. Simulation and
experimental results are presented and commented.
Abstract: Worldwide, most PILC MV underground cables in use
are approaching the end of their design life; hence, failures are likely
to increase. This paper studies the electric field and potential
distributions within the PILC insulted cable containing common
void-defect. The finite element model of the performance of the
belted PILC MV underground cable is presented. The variation of the
electric field stress within the cable using the Finite Element Method
(FEM) is concentrated. The effects of the void-defect within the
insulation are given. Outcomes will lead to deeper understanding of
the modeling of Paper Insulated Lead Covered (PILC) and electric
field response of belted PILC insulted cable containing void defect.
Abstract: Future flood can be predicted using the probable
maximum flood (PMF). PMF is calculated using the historical
discharge or rainfall data considering the other climatic parameters
remaining stationary. However climate is changing globally and the
key climatic variables are temperature, evaporation, rainfall and sea
level rise are likely to change. To develop scenarios to a basin or
catchment scale these important climatic variables should be
considered. Nowadays scenario based on climatic variables is more
suitable than PMF. Six scenarios were developed for a large Fitzroy
basin and presented in this paper.
Abstract: Starting in 2020, an EU-wide CO2-limitation of
95 g/km is scheduled for the average of an OEMs passenger car fleet.
Taking that into consideration additional improvement measures of
the Diesel cycle are necessary in order to reduce fuel consumption
and emissions while boosting, or at the least, keeping performance
values at the same time.
The present article deals with the possibilities of an optimized
air/water charge air cooler, also called iCAC (indirect Charge Air
Cooler) for a Diesel passenger car amongst extreme-boundary
conditions. In this context, the precise objective was to show the
impact of improved intercooling with reference to the engine working
process (fuel consumption and NOx-emissions). Several extremeboundaries
- e.g. varying ambient temperatures or mountainous
routes - that will become very important in the near future regarding
RDE (Real Driving emissions) were subject of the investigation.
With the introduction of RDE in 2017 (EU6c measure), the
controversial NEDC (New European Driving Cycle) will belong to
the past and the OEMs will have to avoid harmful emissions in any
conceivable real life situation.
This is certainly going to lead to optimization-measurements at the
powertrain, which again is going to make the implementation of
iCACs, presently solely used for the premium class, more and more
attractive for compact class cars. The investigations showed a benefit
in FC between 1 and 3% for the iCAC in real world conditions.
Abstract: Carbon nanotube is one of the most attractive materials
for the potential applications of nanotechnology due to its excellent
mechanical, thermal, electrical and optical properties. In this paper we
report a supercapacitor made of nickel foil electrodes, coated with
multiwall carbon nanotubes (MWCNTs) thin film using
electrophoretic deposition (EPD) method. Chemical vapor deposition
method was used for the growth of MWCNTs and ethanol was used as
a hydrocarbon source. High graphitic multiwall carbon nanotube was
found at 750oC analyzing by Raman spectroscopy. We observed the
electrochemical performance of supercapacitor by cyclic
voltammetry. The electrodes of supercapacitor fabricated from
MWCNTs exhibit considerably small equivalent series resistance
(ESR), and a high specific power density. Electrophoretic deposition
is an easy method in fabricating MWCNT electrodes for high
performance supercapacitor.