Abstract: Solution to unsteady Navier-Stokes equation by Splitting method in physical orthogonal algebraic curvilinear coordinate system, also termed 'Non-linear grid system' is presented. The linear terms in Navier-Stokes equation are solved by Crank- Nicholson method while the non-linear term is solved by the second order Adams-Bashforth method. This work is meant to bring together the advantage of Splitting method as pressure-velocity solver of higher efficiency with the advantage of consuming Non-linear grid system which produce more accurate results in relatively equal number of grid points as compared to Cartesian grid. The validation of Splitting method as a solution of Navier-Stokes equation in Nonlinear grid system is done by comparison with the benchmark results for lid driven cavity flow by Ghia and some case studies including Backward Facing Step Flow Problem.
Abstract: In this paper, we consider nested sliding mode control of SISO nonlinear systems, perturbed by bounded matched and unmatched uncertainties. The systems are assumed to be in strict-feedback form. A step wise procedure is introduced to obtain the controller. In each step, a continuous sliding mode controller is designed as virtual control law. Then the next step sliding surface is defined by using this virtual controller. These sliding surfaces are selected as nonlinear static functions of the system states. Finally in the last step, smooth static state feedback control law is determined such that the output reaches the desired set-point while the system is forced arbitrary close to the intersection of sliding surfaces and the states remain bounded.
Abstract: The fractal-shaped orifices are assumed to have a
significant effect on the pressure drop downstream pipe flow due to
their edge self-similarity shape which enhances the mixing
properties. Here, we investigate the pressure drop after these fractals
using a digital micro-manometer at different stations downstream a
turbulent flow pipe then a direct comparison has been made with the
pressure drop measured from regular orifices with the same flow
area. Our results showed that the fractal-shaped orifices have a
significant effect on the pressure drop downstream the flow. Also
the pressure drop measured across the fractal-shaped orifices is
noticed to be lower that that from ordinary orifices of the same flow
areas. This result could be important in designing piping systems
from point of view of losses consideration with the same flow
control area. This is promising to use the fractal-shaped orifices as
flowmeters as they can sense the pressure drop across them
accurately with minimum losses than the regular ones.
Abstract: Dynamic location referencing method is an important technology to shield map differences. These method references objects of the road network by utilizing condensed selection of its real-world geographic properties stored in a digital map database, which overcomes the defections existing in pre-coded location referencing methods. The high attributes completeness requirements and complicated reference point selection algorithm are the main problems of recent researches. Therefore, a dynamic location referencing algorithm combining intersection points selected at the extremities compulsively and road link points selected according to link partition principle was proposed. An experimental system based on this theory was implemented. The tests using Beijing digital map database showed satisfied results and thus verified the feasibility and practicability of this method.
Abstract: For a long time as a result of accommodating car
traffic, planning ideologies in the past put a low priority on public
space, pedestrianism and the role of city space as a meeting place for
urban dwellers. In addition, according to authors such as Jan Gehl,
market forces and changing architectural perceptions began to shift
the focus of planning practice from the integration of public space in
various pockets around the contemporary city to individual buildings.
Eventually, these buildings have become increasingly more isolated
and introverted and have turned their backs to the realm of the public
space adjoining them. As a result of this practice, the traditional
function of public space as a social forum for city dwellers has in
many cases been reduced or even phased out. Author Jane Jacobs
published her seminal book “The Death and Life of Great American
Cities" more than fifty years ago, but her observations and
predictions at the time still ring true today, where she pointed out
how the dramatic increase in car traffic and its accommodation by the
urban planning ideology that was brought about by the Modern
movement has prompted a separation of the uses of the city. At the
same time it emphasizes free standing buildings that threaten urban
space and city life and result in underutilized and lifeless urban cores.
In this discussion context, the aim of this paper is to showcase a
reversal of just such a situation in the case of the Dasoupolis
neighborhood in Strovolos, Cyprus, where enlightened urban design
practice has see the reclamation of pedestrian space in a car
dominated area.
Abstract: This paper proposes a balance control scheme for a biped robot to trace an arbitrary path using image information. While moving, it estimates the zero moment point(ZMP) of the biped robot in the next step using a Kalman filter and renders an appropriate balanced pose of the robot. The ZMP can be calculated from the robot's pose, which is measured from the reference object image acquired by a CCD camera on the robot's head. For simplifying the kinematical model, the coordinates systems of individual joints of each leg are aligned and the robot motion is approximated as an inverted pendulum so that a simple linear dynamics, 3D-LIPM(3D-Linear Inverted Pendulum Mode) can be applied. The efficiency of the proposed algorithm has been proven by the experiments performed on unknown trajectory.
Abstract: This study investigates the in-situ regeneration of deactivated Pt-Pd catalyst in a laboratory-scale catalysis reactor. Different regeneration conditions are tested and the activity and characteristics of regenerated catalysts are analyzed. Experimental results show that the conversion efficiencies of C3H6 by different regenerated Pt-Pd catalysts were significantly improved from 77%, 55% and 41% to 86%, 98% and 99%, respectively. The best regeneration conditions was 52ppm ozone, 500oC, and 10min. Regeneration temperature has more influences than ozone concentration and regeneration time. With the comparisons of characteristics of deactivated catalyst and regenerated catalyst, the major poison species (carbon, metals, chloride, and sulfate) on the spent catalysts can be effectively removed by ozone regeneration.
Abstract: The introduction of mass-customization has enabled
new ways to treat patients within medicine. However, the
introduction of industrialized treatments has also meant new
obstacles. The purpose of this study was to introduce and
theoretically test a method for improving dental crown fit. The
optimization method allocates support points in order to check the
final variation for dental crowns. Three different types of geometries
were tested and compared. The three geometries were also divided
into three sub-geometries: Current method, Optimized method and
Feasible method. The Optimized method, using the whole surface for
support points, provided the best results. The results support the
objective of the study. It also seems that the support optimization
method can dramatically improve the robustness of dental crown
treatments.
Abstract: A submerged horizontal plate type breakwater is
pointed out as an efficient wave protection device for cage culture in
marine fishery. In order to reveal the wave elimination principle of this
type breakwater, boundary element method is utilized to investigate
this problem. The flow field and the trajectory of water particles are
studied carefully. The flow field analysis shows that: the interaction of
incident wave and adverse current above the plate disturbs the water
domain drastically. This can slow down the horizontal velocity and
vertical velocity of the water particles.
Abstract: In multi hop wireless systems, such as ad hoc and
sensor networks, mobile ad hoc network applications are deployed,
security emerges as a central requirement. A particularly devastating
attack is known as the wormhole attack, where two or more malicious
colluding nodes create a higher level virtual tunnel in the network,
which is employed to transport packets between the tunnel end points.
These tunnels emulate shorter links in the network. In which
adversary records transmitted packets at one location in the network,
tunnels them to another location, and retransmits them into the
network. The wormhole attack is possible even if the attacker has not
compromised any hosts and even if all communication provides
authenticity and confidentiality. In this paper, we analyze wormhole
attack nature in ad hoc and sensor networks and existing methods of
the defending mechanism to detect wormhole attacks without require
any specialized hardware. This analysis able to provide in
establishing a method to reduce the rate of refresh time and the
response time to become more faster.
Abstract: In the meat processing industry the substitution of
meat with non-meat ingredients is considered an important strategy
for reducing overall production costs. The main purpose of the
current research was to evaluate differences in physical-chemical
composition of cooked sausage with different legumes additions.
Peas (Pisum sativum), beans (Phaseolus vulgaris) and lentil (Lens
culinaris) were used in preparation of sausages. The legumes at
proportion of 20% of the total weight of meat were added in
sausages. The whole ingredients were mixed, filled into casing,
compressed, cooked and cooled. After storage the samples were
sensory evaluated. The sensory evaluation was carried out using the
nine point hedonic scale and line scale. Sausages without legumes
flour was used as control sample. The main conclusion of the current
research the legumes flour can be successfully used for cooked
sausages production.
Abstract: This paper proposes the method combining artificial neural network with particle swarm optimization (PSO) to implement the maximum power point tracking (MPPT) by controlling the rotor speed of the wind generator. With the measurements of wind speed, rotor speed of wind generator and output power, the artificial neural network can be trained and the wind speed can be estimated. The proposed control system in this paper provides a manner for searching the maximum output power of wind generator even under the conditions of varying wind speed and load impedance.
Abstract: According to the European laws, there is the
possibility of reusing the washing wastes for the environmental
requalification of quarry lakes. The paper deals with the
hydrogeological aspects involved in this possibility, as the
introduction of finest wastes in the quarry lakes can generate
alterations of the hydrogeological setting of the area, and problems
for the future accessibility of the zone. To evaluate the
hydrogeological compatibility of the washing wastes reuse in quarry
lakes a groundwater numerical model was carried out, pointing out
both the hydrogeological feasibility of this intervention and some
guide lines for its optimization, in terms of inflow point with regard
the groundwater flow direction and loss of volume in the quarry lake.
Abstract: Since atmosphere pressure field is an actual envoy of
climatic signal the atmospheric Highs and Lows should be attributed
to the key active focal points within the ocean-atmosphere interplay
system. Here we were set a task to determine how the dynamics of
those centres of action relates to the climate change both on regional
and global scales. For this target the near-surface temperature and
atmospheric pressure differences between the Icelandic Low and the
Azores High were considered. The secular term of phase states of the
system under consideration was found divided into three
nonintersecting subsets. Each of that was put in consequence with
one of three climatic scenarios related to the periods of 1905-1935
(relatively warm phase), 1940-1970 (cold phase) and 1980-2000
(warm phase).
Abstract: This paper presents a simple and effective method for approximate indexing of instances for instance based learning. The method uses an interval tree to determine a good starting search point for the nearest neighbor. The search stops when an early stopping criterion is met. The method proved to be very effective especially when only the first nearest neighbor is required.
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: Activity-Based Costing (ABC) which has become an important aspect of manufacturing/service organizations can be defined as a methodology that measures the cost and performance of activities, resources and cost objects. It can be considered as an alternative paradigm to traditional cost-based accounting systems. The objective of this paper is to illustrate an application of ABC method and to compare the results of ABC with traditional costing methods. The results of the application highlight the weak points of traditional costing methods and an S-Curve obtained is used to identify the undercosted and overcosted products of the firm.
Abstract: In this work a software simulation model has been
proposed for two driven wheels mobile robot path planning; that can
navigate in dynamic environment with static distributed obstacles.
The work involves utilizing Bezier curve method in a proposed N
order matrix form; for engineering the mobile robot path. The Bezier
curve drawbacks in this field have been diagnosed. Two directions:
Up and Right function has been proposed; Probability Recursive
Function (PRF) to overcome those drawbacks.
PRF functionality has been developed through a proposed;
obstacle detection function, optimization function which has the
capability of prediction the optimum path without comparison
between all feasible paths, and N order Bezier curve function that
ensures the drawing of the obtained path.
The simulation results that have been taken showed; the mobile
robot travels successfully from starting point and reaching its goal
point. All obstacles that are located in its way have been avoided.
This navigation is being done successfully using the proposed PRF
techniques.
Abstract: This paper developed the c-Chart based on a Zero- Inflated Poisson (ZIP) processes that approximated by a geometric distribution with parameter p. The p estimated that fit for ZIP distribution used in calculated the mean, median, and variance of geometric distribution for constructed the c-Chart by three difference methods. For cg-Chart, developed c-Chart by used the mean and variance of the geometric distribution constructed control limits. For cmg-Chart, the mean used for constructed the control limits. The cme- Chart, developed control limits of c-Chart from median and variance values of geometric distribution. The performance of charts considered from the Average Run Length and Average Coverage Probability. We found that for an in-control process, the cg-Chart is superior for low level of mean at all level of proportion zero. For an out-of-control process, the cmg-Chart and cme-Chart are the best for mean = 2, 3 and 4 at all level of parameter.
Abstract: Among many different methods that are used for
optimizing different engineering problems mathematical (numerical)
optimization techniques are very important because they can easily
be used and are consistent with most of engineering problems. Many
studies and researches are done on stability analysis of three
dimensional (3D) slopes and the relating probable slip surfaces and
determination of factors of safety, but in most of them force
equilibrium equations, as in simplified 2D methods, are considered
only in two directions. In other words for decreasing mathematical
calculations and also for simplifying purposes the force equilibrium
equation in 3rd direction is omitted. This point is considered in just a
few numbers of previous studies and most of them have only given a
factor of safety and they haven-t made enough effort to find the most
probable slip surface. In this study shapes of the slip surfaces are
modeled, and safety factors are calculated considering the force
equilibrium equations in all three directions, and also the moment
equilibrium equation is satisfied in the slip direction, and using
nonlinear programming techniques the shape of the most probable
slip surface is determined. The model which is used in this study is a
3D model that is composed of three upper surfaces which can cover
all defined and probable slip surfaces. In this research the meshing
process is done in a way that all elements are prismatic with
quadrilateral cross sections, and the safety factor is defined on this
quadrilateral surface in the base of the element which is a part of the
whole slip surface. The method that is used in this study to find the
most probable slip surface is the non-linear programming method in
which the objective function that must get optimized is the factor of
safety that is a function of the soil properties and the coordinates of
the nodes on the probable slip surface. The main reason for using
non-linear programming method in this research is its quick
convergence to the desired responses. The final results show a good
compatibility with the previously used classical and 2D methods and
also show a reasonable convergence speed.