Abstract: This research details a Computational Fluid Dynamics (CFD) approach to model fluid flow in a journal bearing with 8 equispaced semi-circular axial grooves. Water is used as the lubricant and is fed from one end of the bearing to the other, under pressure. The geometry of the bearing is modeled using a commercially available modeling software GAMBIT and the flow analysis is performed using a dedicated CFD analysis software FLUENT. The pressure distribution in the bearing clearance is obtained from FLUENT for various whirl ratios and is used to calculate the hydrodynamic force components in the radial and tangential direction of the bearing. These values along with the various whirl speeds can be used to do a regression analysis to determine the stiffness and damping coefficients. The values obtained are then compared with the stiffness and damping coefficients of a 3 Axial groove water lubricated journal bearing and those obtained from a FORTRAN code for a similar bearing.
Abstract: The purpose of this study is mainly to predict collision
frequency on the horizontal tangents combined with vertical curves
using artificial neural network methods. The proposed ANN models
are compared with existing regression models. First, the variables
that affect collision frequency were investigated. It was found that
only the annual average daily traffic, section length, access density,
the rate of vertical curvature, smaller curve radius before and after
the tangent were statistically significant according to related
combinations. Second, three statistical models (negative binomial,
zero inflated Poisson and zero inflated negative binomial) were
developed using the significant variables for three alignment
combinations. Third, ANN models are developed by applying the
same variables for each combination. The results clearly show that
the ANN models have the lowest mean square error value than those
of the statistical models. Similarly, the AIC values of the ANN
models are smaller to those of the regression models for all the
combinations. Consequently, the ANN models have better statistical
performances than statistical models for estimating collision
frequency. The ANN models presented in this paper are
recommended for evaluating the safety impacts 3D alignment
elements on horizontal tangents.
Abstract: Most of the commercial gluten free products are
nutritionally inferior when compared to gluten containing
counterparts as manufacturers most often use the refined flours and
starches. So it is possible that people on gluten free diet have low
intake of fibre content. The foxtail millet flour and copra meal are
gluten free and have high fibre and protein contents. The formulation
of fibre rich gluten free cookies was optimized by response surface
methodology considering independent process variables as proportion
of Foxtail millet (Setaria italica) flour in mixed flour, fat content and
guar gum. The sugar, sodium chloride, sodium bicarbonates and
water were added in fixed proportion as 60, 1.0, 0.4 and 20% of
mixed flour weight, respectively. Optimum formulation obtained for
maximum spread ratio, fibre content, surface L-value, overall
acceptability and minimum breaking strength were 80% foxtail millet
flour in mixed flour, 42.8 % fat content and 0.05% guar gum.
Abstract: The behavior of Radial Basis Function (RBF) Networks greatly depends on how the center points of the basis functions are selected. In this work we investigate the use of instance reduction techniques, originally developed to reduce the storage requirements of instance based learners, for this purpose. Five Instance-Based Reduction Techniques were used to determine the set of center points, and RBF networks were trained using these sets of centers. The performance of the RBF networks is studied in terms of classification accuracy and training time. The results obtained were compared with two Radial Basis Function Networks: RBF networks that use all instances of the training set as center points (RBF-ALL) and Probabilistic Neural Networks (PNN). The former achieves high classification accuracies and the latter requires smaller training time. Results showed that RBF networks trained using sets of centers located by noise-filtering techniques (ALLKNN and ENN) rather than pure reduction techniques produce the best results in terms of classification accuracy. The results show that these networks require smaller training time than that of RBF-ALL and higher classification accuracy than that of PNN. Thus, using ALLKNN and ENN to select center points gives better combination of classification accuracy and training time. Our experiments also show that using the reduced sets to train the networks is beneficial especially in the presence of noise in the original training sets.
Abstract: This study examines whether contrived success on a
task closely related to school subjects would promote students-
self-efficacy. In our previous study, junior high school students who
experienced contrived success on anagram tasks raised their sense of
self-efficacy and kept it high for a year.We tried to replicate that study,
substituting calculation tasks for the anagrams. One hundred eighteen
junior high school students participated in this study, 18 of whom were
surreptitiously given easier tasks than their classmates. Those students
with easier tasks outperformed their peers and thereby raised their
sense of self-efficacy. However, elevated self-efficacy did not persist,
falling to the starting level after only three months.
Abstract: The notion of k-fuzzy ideals of semirings was introduced
by Kim and Park in 1996. In 2003, Dutta and Kar introduced
a notion of ternary semirings. This structure is a generalization of
ternary rings and semirings. The main purpose of this paper is to
introduce and study k-fuzzy ideals in ternary semirings analogous to
k-fuzzy ideals in semirings considered by Kim and Park.
Abstract: The purpose of this paper is to demonstrate the ability
of a genetic programming (GP) algorithm to evolve a team of data
classification models. The GP algorithm used in this work is
“multigene" in nature, i.e. there are multiple tree structures (genes)
that are used to represent team members. Each team member assigns
a data sample to one of a fixed set of output classes. A majority vote,
determined using the mode (highest occurrence) of classes predicted
by the individual genes, is used to determine the final class
prediction. The algorithm is tested on a binary classification problem.
For the case study investigated, compact classification models are
obtained with comparable accuracy to alternative approaches.
Abstract: This paper investigates the development of weld zone
in Resistance Spot Welding (RSW) which focuses on weld nugget and Heat Affected Zone (HAZ). The effects of four factors namely
weld current, weld time, electrode force and hold time were studied using a general 24 factorial design augmented by five centre points. The results of the analysis showed that all selected factors except
hold time exhibit significant effect on weld nugget radius and HAZ size. Optimization of the welding parameters (weld current, weld
time and electrode force) to normalize weld nugget and to minimize
HAZ size was then conducted using Central Composite Design (CCD) in Response Surface Methodology (RSM) and the optimum
parameters were determined. A regression model for radius of weld nugget and HAZ size was developed and its adequacy was evaluated.
The experimental results obtained under optimum operating conditions were then compared with the predicted values and were
found to agree satisfactorily with each other
Abstract: Heat source addition to the axisymmetric supersonic
inlet may improve the performance parameters, which will increase
the inlet efficiency. In this investigation the heat has been added to
the flow field at some distance ahead of an axisymmetric inlet by
adding an imaginary thermal source upstream of cowl lip. The effect
of heat addition on the drag coefficient, mass flow rate and the
overall efficiency of the inlet have been investigated. The results
show that heat addition causes flow separation, hence to prevent this
phenomena, roughness has been added on the spike surface.
However, heat addition reduces the drag coefficient and the inlet
mass flow rate considerably. Furthermore, the effects of position,
size, and shape on the inlet performance were studied. It is found that
the thermal source deflects the flow streamlines. By improper
location of the thermal source, the optimum condition has been
obtained. For the optimum condition, the drag coefficient is
considerably reduced and the inlet mass flow rate and its efficiency
have been increased slightly. The optimum shape of the heat source
is obtained too.
Abstract: The designing of charge pump with high gain Op-
Amp is a challenging task for getting faithful response .Design of
high performance phase locked loop require ,a design of high
performance charge pump .We have designed a operational amplifier
for reducing the error caused by high speed glitch in a transistor and
mismatch currents . A separate Op-Amp has designed in 180 nm
CMOS technology by CADENCE VIRTUOSO tool. This paper
describes the design of high performance charge pump for GHz
CMOS PLL targeting orthogonal frequency division multiplexing
(OFDM) application. A high speed low power consumption Op-Amp
with more than 500 MHz bandwidth has designed for increasing the
speed of charge pump in Phase locked loop.
Abstract: The aim of the work was to attenuate the vibration amplitude in CESNA 172 airplane wing by using Functionally Graded Material instead of uniform or composite material. Wing strength was achieved by means of stress analysis study, while wing vibration amplitudes and shapes were achieved by means of Modal and Harmonic analysis. Results were verified by applying the methodology in a simple cantilever plate to the simple model and the results were promising and the same methodology can be applied to the airplane wing model. Aluminum models, Titanium models, and functionally graded materials of Aluminum and titanium results were compared to show a great vibration attenuation after using the FGM. Optimization in FGM gradation satisfied our objective of reducing and attenuating the vibration amplitudes to show the effect of using FGM in vibration behavior. Testing the Aluminum rich models, and comparing it with the titanium rich model was an optimization in this paper. Results have shown a significant attenuation in vibration magnitudes when using FGM instead of Titanium Plate, and Aluminium wing with FGM Spurs instead of Aluminium wings. It was also recommended that in future, changing the graphical scale to 1:10 or even 1:1 when the computers- capabilities allow.
Abstract: A phorbol-12-myristate-13-acetate (TPA) is a synthetic analogue of phorbol ester (PE), a natural toxic compound of Euphorbiaceae plant. The oil extracted from plants of this family is useful source for primarily biofuel. However this oil might also be used as a foodstuff due to its significant nutrition content. The limitations for utilizing the oil as a foodstuff are mainly due to a toxicity of PE. Currently, a majority of PE detoxification processes are expensive as include multi steps alcohol extraction sequence.
Ozone is considered as a strong oxidative agent. It reacts with PE by attacking the carbon-carbon double bond of PE. This modification of PE molecular structure yields a non toxic ester with high lipid content.
This report presents data on development of simple and cheap PE detoxification process with water application as a buffer and ozone as reactive component. The core of this new technique is an application for a new microscale plasma unit to ozone production and the technology permits ozone injection to the water-TPA mixture in form of microbubbles.
The efficacy of a heterogeneous process depends on the diffusion coefficient which can be controlled by contact time and interfacial area. The low velocity of rising microbubbles and high surface to volume ratio allow efficient mass transfer to be achieved during the process. Direct injection of ozone is the most efficient way to process with such highly reactive and short lived chemical.
Data on the plasma unit behavior are presented and the influence of gas oscillation technology on the microbubble production mechanism has been discussed. Data on overall process efficacy for TPA degradation is shown.
Abstract: This paper is aimed to study the roles of leadership and innovation in the development of local people based ecotourism
services. The survey is conducted in Candirejo village, Borobudur District, Magelang Regency. The study of a descriptive approach is employed to identify people's behavior in ecotourism services. The results showed that ecotourism services have developed and provided benefits to the people. The roles of leadership and innovation interact positively with a cooperative to organize an ecotourism services management. The leadership is able to identify substances, to do the vision and missions of environmental and cultural conservation. The innovation provides alternative development efforts and increases the added value of ecotourism. The cooperative management was able to support a process to realize the goals of ecotourism, to build participation and communication, and to perform organizational learning. The phenomenon of the leadership in the Candirejo ecotourism enriches the studies of the ecotourism management. During this time, the ecotourism management is always associated
with the standard management of national park. The ecotourism management of Candirejo is considered successful even outside the national park management.
Abstract: System is using multiple processors for computing and information processing, is increasing rapidly speed operation of these systems compared with single processor systems, very significant impact on system performance is increased .important differences to yield a single multi-processor cpu, the scheduling policies, to reduce the implementation time of all processes. Notwithstanding the famous algorithms such as SPT, LPT, LSPT and RLPT for scheduling and there, but none led to the answer are not optimal.In this paper scheduling using genetic algorithms and innovative way to finish the whole process faster that we do and the result compared with three algorithms we mentioned.
Abstract: This paper compares the heuristic Global Search
Techniques; Genetic Algorithm, Particle Swarm Optimization,
Simulated Annealing, Generalized Pattern Search, genetic algorithm
hybridized with Nelder–Mead and Generalized pattern search
technique for tuning of fuzzy PID controller for Puma 560. Since the
actual control is in joint space ,inverse kinematics is used to generate
various joint angles correspoding to desired cartesian space
trajectory. Efficient dynamics and kinematics are modeled on Matlab
which takes very less simulation time. Performances of all the tuning
methods with and without disturbance are compared in terms of ITSE
in joint space and ISE in cartesian space for spiral trajectory tracking.
Genetic Algorithm hybridized with Generalized Pattern Search is
showing best performance.
Abstract: Business rules are widely used within the services
sector. They provide consistency and allow relatively unskilled staff
to process complex transactions correctly. But there are many
examples where the rules themselves have an impact on the costs and
profits of an organisation. Financial services, transport and human
services are areas where the rules themselves can impact the bottom
line in a predictable way. If this is the case, how can we find that set
of rules that maximise profit, performance or customer service, or
any other key performance indicators? The manufacturing, energy
and process industries have embraced mathematical optimisation
techniques to improve efficiency, increase production and so on. This
paper explores several real world (but simplified) problems in the
services sector and shows how business rules can be optimised. It
also examines the similarities and differences between the service
and other sectors, and how optimisation techniques could be used to
deliver similar benefits.
Abstract: Feeder is one of the airships of the Multibody Advanced Airship for Transport (MAAT) system, under development within the EU FP7 project. MAAT is based on a modular concept composed of two different parts that have the possibility to join; respectively they are the so-called Cruiser and Feeder, designed on the lighter than air principle. Feeder, also named ATEN (Airship Transport Elevator Network), is the smaller one which joins the bigger one, Cruiser, also named PTAH (Photovoltaic modular Transport Airship for High altitude),envisaged to happen at 15km altitude. During the MAAT design phase, the aerodynamic studies of the both airships and their interactions are analyzed. The objective of these studies is to understand the aerodynamic behavior of all the preselected configurations, as an important element in the overall MAAT system design. The most of these configurations are only simulated by CFD, while the most feasible one is experimentally analyzed in order to validate and thrust the CFD predictions. This paper presents the numerical and experimental investigation of the Feeder “conical like" shape configuration. The experiments are focused on the aerodynamic force coefficients and the pressure distribution over the Feeder outer surface, while the numerical simulation cover also the analysis of the velocity and pressure distribution. Finally, the wind tunnel experiment is compared with its CFD model in order to validate such specific simulations with respective experiments and to better understand the difference between the wind tunnel and in-flight circumstances.
Abstract: The intermittent connectivity modifies the “always
on" network assumption made by all the distributed query processing
systems. In modern- day systems, the absence of network
connectivity is considered as a fault. Since the last upload, it might
not be feasible to transmit all the data accumulated right away over
the available connection. It is possible that vital information may be
delayed excessively when the less important information takes place
of the vital information. Owing to the restricted and uneven
bandwidth, it is vital that the mobile nodes make the most
advantageous use of the connectivity when it arrives. Hence, in order
to select the data that needs to be transmitted first, some sort of data
prioritization is essential. A continuous query processing system for
intermittently connected mobile networks that comprises of a delaytolerant
continuous query processor distributed across the mobile
hosts has been proposed in this paper. In addition, a mechanism for
prioritizing query results has been designed that guarantees enhanced
accuracy and reduced delay. It is illustrated that our architecture
reduces the client power consumption, increases query efficiency by
the extensive simulation results.
Abstract: In this paper a low cost knowledge base system (KBS)
framework is proposed for design of deep drawing die and procedure
for developing system modules. The task of building the system is
structured into different modules for major activities of design of
deep drawing die. A manufacturability assessment module of the
proposed framework is developed to check the manufacturability of
deep drawn parts. The technological knowledge is represented by
using IF- THEN rules and it is coded in AutoLISP language. The
module is designed to be loaded into the prompt area of AutoCAD.
The cost of implementation of proposed system makes it affordable
for small and medium scale sheet metal industries.
Abstract: An optimal solution for a large number of constraint
satisfaction problems can be found using the technique of
substitution and elimination of variables analogous to the technique
that is used to solve systems of equations. A decision function
f(A)=max(A2) is used to determine which variables to eliminate. The
algorithm can be expressed in six lines and is remarkable in both its
simplicity and its ability to find an optimal solution. However it is
inefficient in that it needs to square the updated A matrix after each
variable elimination. To overcome this inefficiency the algorithm is
analyzed and it is shown that the A matrix only needs to be squared
once at the first step of the algorithm and then incrementally updated
for subsequent steps, resulting in significant improvement and an
algorithm complexity of O(n3).