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: This research proposed a new design of helmet-shaped
array transcranial magnetic stimulation coil system. It was constructed
using several sagittal directional wires and several coronal directional
wires. By varying the current direction and strength on each wire, this
array coil system could be constructed into the circular coil and
figure-eight coil of different size. Also, this proposed coil system can
flexibly not only change the stimulation location, range, type and
strength, but also change the shape and the channel number of coil
dynamically.
Abstract: In this study, it is investigated the stability boundary of
Functionally Graded (FG) panel under the heats and supersonic
airflows. Material properties are assumed to be temperature
dependent, and a simple power law distribution is taken. First-order
shear deformation theory (FSDT) of plate is applied to model the
panel, and the von-Karman strain- displacement relations are
adopted to consider the geometric nonlinearity due to large
deformation. Further, the first-order piston theory is used to model the
supersonic aerodynamic load acting on a panel and Rayleigh damping
coefficient is used to present the structural damping. In order to find a
critical value of the speed, linear flutter analysis of FG panels is
performed. Numerical results are compared with the previous works,
and present results for the temperature dependent material are
discussed in detail for stability boundary of the panel with various
volume fractions, and aerodynamic pressures.
Abstract: Steganography meaning covered writing. Steganography includes the concealment of information within computer files [1]. In other words, it is the Secret communication by hiding the existence of message. In this paper, we will refer to cover image, to indicate the images that do not yet contain a secret message, while we will refer to stego images, to indicate an image with an embedded secret message. Moreover, we will refer to the secret message as stego-message or hidden message. In this paper, we proposed a technique called RGB intensity based steganography model as RGB model is the technique used in this field to hide the data. The methods used here are based on the manipulation of the least significant bits of pixel values [3][4] or the rearrangement of colors to create least significant bit or parity bit patterns, which correspond to the message being hidden. The proposed technique attempts to overcome the problem of the sequential fashion and the use of stego-key to select the pixels.
Abstract: Implementation of response surface methodology (RSM) was employed to study the effects of two factor (rubber clearance and round per minute) in brown rice peeling machine of The optimal BROKENS yield (19.02, average of three repeats),.The optimized composition derived from RSM regression was analyzed using Regression analysis and Analysis of Variance (ANOVA). At a significant level α = 0.05, the values of Regression coefficient, R 2 (adj)were 97.35 % and standard deviation were 1.09513. The independent variables are initial rubber clearance, and round per minute parameters namely. The investigating responses are final rubber clearance, and round per minute (RPM). The restriction of the optimization is the designated.
Abstract: In this paper, an intelligent automatic parking control method is proposed. First, the dynamical equation of the rear parking control is derived. Then a fuzzy logic control is proposed to perform the parking planning process. Further, a rear neural network is proposed for the steering control. Through the simulations and experiments, the intelligent auto-parking mode controllers have been shown to achieve the demanded goals with satisfactory control performance and to guarantee the system robustness under parametric variations and external disturbances. To improve some shortcomings and limitations in conventional parking mode control and further to reduce consumption time and prime cost.
Abstract: In this paper we consider a nonlinear feedback control
called augmented automatic choosing control (AACC) for nonlinear
systems with constrained input using weighted gradient optimization
automatic choosing functions. Constant term which arises from
linearization of a given nonlinear system is treated as a coefficient of
a stable zero dynamics. Parameters of the control are suboptimally
selected by maximizing the stable region in the sense of Lyapunov
with the aid of a genetic algorithm. This approach is applied to a
field excitation control problem of power system to demonstrate the
splendidness of the AACC. Simulation results show that the new
controller can improve performance remarkably well.
Abstract: This paper presents an exact pruning algorithm with
adaptive pruning interval for general dynamic neural networks
(GDNN). GDNNs are artificial neural networks with internal dynamics.
All layers have feedback connections with time delays to the
same and to all other layers. The structure of the plant is unknown, so
the identification process is started with a larger network architecture
than necessary. During parameter optimization with the Levenberg-
Marquardt (LM) algorithm irrelevant weights of the dynamic neural
network are deleted in order to find a model for the plant as
simple as possible. The weights to be pruned are found by direct
evaluation of the training data within a sliding time window. The
influence of pruning on the identification system depends on the
network architecture at pruning time and the selected weight to be
deleted. As the architecture of the model is changed drastically during
the identification and pruning process, it is suggested to adapt the
pruning interval online. Two system identification examples show
the architecture selection ability of the proposed pruning approach.
Abstract: The paper deals with hydrodynamics of liquid-gas
layers under gas streaming through liquid layer on perforated plates
in column apparatuses. The plates with large apertures have been
investigated especially. It was shown that hydrodynamic regularities
for these plates are essentially different from known laws for foam
forming on fine-perforated plates. Main regularities of liquid-gas
interaction on plates with large apertures have been established.
Abstract: Independent component analysis can estimate unknown
source signals from their mixtures under the assumption that the
source signals are statistically independent. However, in a real environment,
the separation performance is often deteriorated because
the number of the source signals is different from that of the sensors.
In this paper, we propose an estimation method for the number of
the sources based on the joint distribution of the observed signals
under two-sensor configuration. From several simulation results, it
is found that the number of the sources is coincident to that of
peaks in the histogram of the distribution. The proposed method can
estimate the number of the sources even if it is larger than that of
the observed signals. The proposed methods have been verified by
several experiments.
Abstract: Biomechanical properties of infantile aorta in vitro in
cases of different standard anastomoses: end-to-end (ETE), extended
anastomosis end-to-end (EETE) and subclavian flap aortoplasty
(SFA) used for surgical correction of coarctation were analyzed to
detect the influence of the method on the biomechanics of infantile
aorta and possible changes in haemodinamics. 10 specimens of native
aorta, 3 specimens with ETE, 4 EEET and 3 SFA were investigated.
The experiments showed a non-linear relationship between stress and
strain in the infantile aorta, the modulus of elasticity of the aortic wall
increased with the increase of inner pressure. In the case of
anastomosis end-to-end the modulus was almost constant, relevant to
the modulus of elasticity of the aorta with the inner pressure 100-120
mmHg. The anastomoses EETE and SFA showed elastic properties
closer to native aorta, the stiffness of ETE did not change with the
changes in inner pressure.
Abstract: The paper suggests for the first time the use of dynamic programming techniques for optimal risk reduction in the railway industry. It is shown that by using the concept ‘amount of removed risk by a risk reduction option’, the problem related to optimal allocation of a fixed budget to achieve a maximum risk reduction in the railway industry can be reduced to an optimisation problem from dynamic programming. For n risk reduction options and size of the available risk reduction budget B (expressed as integer number), the worst-case running time of the proposed algorithm is O (n x (B+1)), which makes the proposed method a very efficient tool
for solving the optimal risk reduction problem in the railway industry.
Abstract: Application of Expert System in the area of agriculture would take the form of Integrated Crop Management decision aids and would encompass water management, fertilizer management, crop protection systems and identification of implements. In order to remain competitive, the modern farmer often relies on agricultural specialists and advisors to provide information for decision-making. An expert system normally composed of a knowledge base (information, heuristics, etc.), inference engine (analyzes knowledge base), and end user interface (accepting inputs, generating outputs). Software named 'CROP-9-DSS' incorporating all modern features like, graphics, photos, video clippings etc. has been developed. This package will aid as a decision support system for identification of pest and diseases with control measures, fertilizer recommendation system, water management system and identification of farm implements for leading crops of Kerala (India) namely Coconut, Rice, Cashew, Pepper, Banana, four vegetables like Amaranthus, Bhindi, Brinjal and Cucurbits. 'CROP-9-DSS' will act as an expert system to agricultural officers, scientists in the field of agriculture and extension workers for decision-making and help them in suggesting suitable recommendations.
Abstract: In this study, we sought to investigate the mercury
removal efficiency of manganese oxides from natural gas. The
fundamental studies on mercury removal with manganese oxides
sorbents were carried out in a laboratory scale fixed bed reactor at 30
°C with a mixture of methane (20%) and nitrogen gas laden with 4.8
ppb of elemental mercury. Manganese oxides with varying surface
area and crystalline phase were prepared by conventional precipitation
method in this study. The effects of surface area, crystallinity and
other metal oxides on mercury removal efficiency were investigated.
Effect of Ag impregnation on mercury removal efficiency was also
investigated. Ag supported on metal oxide such titania and zirconia as
reference materials were also used in this study for comparison. The
characteristics of mercury removal reaction with manganese oxide
was investigated using a temperature programmed desorption (TPD)
technique.
Manganese oxides showed very high Hg removal activity (about
73-93% Hg removal) for first time use. Surface area of the manganese
oxide samples decreased after heat-treatment and resulted in complete
loss of Hg removal ability for repeated use after Hg desorption in the
case of amorphous MnO2, and 75% loss of the initial Hg removal
activity for the crystalline MnO2. Mercury desorption efficiency of
crystalline MnO2 was very low (37%) for first time use and high (98%)
after second time use. Residual potassium content in MnO2 may have
some effect on the thermal stability of the adsorbed Hg species.
Desorption of Hg from manganese oxides occurs at much higher
temperatures (with a peak at 400 °C) than Ag/TiO2 or Ag/ZrO2.
Mercury may be captured on manganese oxides in the form of mercury
manganese oxide.
Abstract: Many multimedia communication applications require a
source to transmit messages to multiple destinations subject to quality
of service (QoS) delay constraint. To support delay constrained
multicast communications, computer networks need to guarantee an
upper bound end-to-end delay from the source node to each of
the destination nodes. This is known as multicast delay problem.
On the other hand, if the same message fails to arrive at each
destination node at the same time, there may arise inconsistency and
unfairness problem among users. This is related to multicast delayvariation
problem. The problem to find a minimum cost multicast
tree with delay and delay-variation constraints has been proven to
be NP-Complete. In this paper, we propose an efficient heuristic
algorithm, namely, Economic Delay and Delay-Variation Bounded
Multicast (EDVBM) algorithm, based on a novel heuristic function,
to construct an economic delay and delay-variation bounded multicast
tree. A noteworthy feature of this algorithm is that it has very high
probability of finding the optimal solution in polynomial time with
low computational complexity.
Abstract: The main goal of this seminal paper is to introduce the
application of Wireless Sensor Networks (WSN) in long distance
infrastructure monitoring (in particular in pipeline infrastructure
monitoring) – one of the on-going research projects by the Wireless
Communication Research Group at the department of Electronic and
Computer Engineering, Nnamdi Azikiwe University, Awka. The
current sensor network architectures for monitoring long distance
pipeline infrastructures are previewed. These are wired sensor
networks, RF wireless sensor networks, integrated wired and wireless
sensor networks. The reliability of these architectures is discussed.
Three reliability factors are used to compare the architectures in
terms of network connectivity, continuity of power supply for the
network, and the maintainability of the network. The constraints and
challenges of wireless sensor networks for monitoring and protecting
long distance pipeline infrastructure are discussed.
Abstract: A parametric study of a mixed-compression
supersonic inlet is performed and reported. The effects of inlet Mach
Numbers, varying from 4 to 10, and angle of attack, varying from 0
to 10, are reported for a constant inlet dynamic pressure. The paper
looked at the variations of mass flow rates through the inlet, gain in
entropy through the inlet, and the angles of the external oblique
shocks. The mass flow rates were found to decrease monotonically
with Mach numbers and increase with angle of attacks. On the other
hand the entropy gain through the inlet increased with increasing
Mach number and angle of attack. The variation in static pressure
was found to be identical from the inlet throat to the exit for Mach
number values higher than 6.
Abstract: In this paper we investigate the watermarking authentication when applied to medical imagery field. We first give an overview of watermarking technology by paying attention to fragile watermarking since it is the usual scheme for authentication.We then analyze the requirements for image authentication and integrity in medical imagery, and we show finally that invertible schemes are the best suited for this particular field. A well known authentication method is studied. This technique is then adapted here for interleaving patient information and message authentication code with medical images in a reversible manner, that is using lossless compression. The resulting scheme enables on a side the exact recovery of the original image that can be unambiguously authenticated, and on the other side, the patient information to be saved or transmitted in a confidential way. To ensure greater security the patient information is encrypted before being embedded into images.
Abstract: Defense and Aerospace environment is continuously
striving to keep up with increasingly sophisticated Information
Technology (IT) in order to remain effective in today-s dynamic and
unpredictable threat environment. This makes IT one of the largest
and fastest growing expenses of Defense. Hundreds of millions of
dollars spent a year on IT projects. But, too many of those millions
are wasted on costly mistakes. Systems that do not work properly,
new components that are not compatible with old ones, trendy new
applications that do not really satisfy defense needs or lost through
poorly managed contracts.
This paper investigates and compiles the effective strategies that
aim to end exasperation with low returns and high cost of
Information Technology acquisition for defense; it tries to show how
to maximize value while reducing time and expenditure.
Abstract: This paper presents a silicon controller rectifier (SCR)
based ESD protection circuit for IC. The proposed ESD protection
circuit has low trigger voltage and high holding voltage compared with
conventional SCR ESD protection circuit. Electrical characteristics of
the proposed ESD protection circuit are simulated and analyzed using
TCAD simulator. The proposed ESD protection circuit verified
effective low voltage ESD characteristics with low trigger voltage and
high holding voltage.