Abstract: We constructed a method of phase unwrapping for a typical wave-front by utilizing the maximizer of the posterior marginal (MPM) estimate corresponding to equilibrium statistical mechanics of the three-state Ising model on a square lattice on the basis of an analogy between statistical mechanics and Bayesian inference. We investigated the static properties of an MPM estimate from a phase diagram using Monte Carlo simulation for a typical wave-front with synthetic aperture radar (SAR) interferometry. The simulations clarified that the surface-consistency conditions were useful for extending the phase where the MPM estimate was successful in phase unwrapping with a high degree of accuracy and that introducing prior information into the MPM estimate also made it possible to extend the phase under the constraint of the surface-consistency conditions with a high degree of accuracy. We also found that the MPM estimate could be used to reconstruct the original wave-fronts more smoothly, if we appropriately tuned hyper-parameters corresponding to temperature to utilize fluctuations around the MAP solution. Also, from the viewpoint of statistical mechanics of the Q-Ising model, we found that the MPM estimate was regarded as a method for searching the ground state by utilizing thermal fluctuations under the constraint of the surface-consistency condition.
Abstract: The unanticipated brittle fracture of connection of the
steel moment resisting frame (SMRF) occurred in 1994 the Northridge
earthquake. Since then, the researches for the vulnerability of
connection of the existing SMRF and for rehabilitation of those
buildings were conducted. This paper suggests performance-based
optimal seismic retrofit technique using connection upgrade. For
optimal design, a multi-objective genetic algorithm(NSGA-II) is used.
One of the two objective functions is to minimize initial cost and
another objective function is to minimize lifetime seismic damages
cost. The optimal algorithm proposed in this paper is performed
satisfying specified performance objective based on FEMA 356. The
nonlinear static analysis is performed for structural seismic
performance evaluation. A numerical example of SAC benchmark
SMRF is provided using the performance-based optimal seismic
retrofit technique proposed in this paper
Abstract: One way for optimum loading of overdimensioning
conveyers is speed (capacity) decrement, with attention for
production capabilities and demands. At conveyers which drives with
three phase slip-ring induction motor, technically reasonable solution
for conveyer (driving motors) speed regulation is using constant
torque subsynchronous cascade with static semiconductor converter
and transformer for energy reversion to the power network. In the
paper is described mathematical model for parameter calculation of
two-motors 6 kV subsynchronous cascade. It is also demonstrated
that applying of this cascade gave several good properties, foremost
in electrical energy saving, also in improving of other energy
indexes, and finally that results in cost reduction of complete
electrical motor drive.
Abstract: Querying a data source and routing data towards sink
becomes a serious challenge in static wireless sensor networks if sink
and/or data source are mobile. Many a times the event to be observed
either moves or spreads across wide area making maintenance of
continuous path between source and sink a challenge. Also, sink can
move while query is being issued or data is on its way towards sink.
In this paper, we extend our already proposed Grid Based Data
Dissemination (GBDD) scheme which is a virtual grid based
topology management scheme restricting impact of movement of
sink(s) and event(s) to some specific cells of a grid. This obviates the
need for frequent path modifications and hence maintains continuous
flow of data while minimizing the network energy consumptions.
Simulation experiments show significant improvements in network
energy savings and average packet delay for a packet to reach at sink.
Abstract: The article is devoted to Kazakh repatriates and their
migration to Kazakhstan as historical homeland, and also addresses
the problem of migrants- adaptation in the republic, particularly in
Almaty oblast (region). The authors used up-to-date statictics and
materials of the Department of Migration Committee to analyze the
newcomers- number and features of the repatriate-s location in this
oblast. Having studied this region they were able to identify the main
reasons why Kazakh Diaspora in Central Asia, Iran, Avganistana and
Turkey is eager to come back to their historic homeland along with
repatriates adaptation to the republic.
Abstract: Power flow (PF) study, which is performed to
determine the power system static states (voltage magnitudes and
voltage angles) at each bus to find the steady state operating
condition of a system, is very important and is the most frequently
carried out study by power utilities for power system planning,
operation and control. In this paper, a counterpropagation neural
network (CPNN) is proposed to solve power flow problem under
different loading/contingency conditions for computing bus voltage
magnitudes and angles of the power system. The counterpropagation
network uses a different mapping strategy namely
counterpropagation and provides a practical approach for
implementing a pattern mapping task, since learning is fast in this
network. The composition of the input variables for the proposed
neural network has been selected to emulate the solution process of a
conventional power flow program. The effectiveness of the proposed
CPNN based approach for solving power flow is demonstrated by
computation of bus voltage magnitudes and voltage angles for
different loading conditions and single line-outage contingencies in
IEEE 14-bus system.
Abstract: This paper concerns about the experimental and
numerical investigations of energy absorption and axial tearing
behaviour of aluminium 6060 circular thin walled tubes under static
axial compression. The tubes are received in T66 heat treatment
condition with fixed outer diameter of 42mm, thickness of 1.5mm
and length of 120mm. The primary variables are the conical die
angles (15°, 20° and 25°). Numerical simulations are carried on
ANSYS/LS-DYNA software tool, for investigating the effect of
friction between the tube and the die.
Abstract: A system for market identification (SMI) is presented.
The resulting representations are multivariable dynamic demand
models. The market specifics are analyzed. Appropriate models and
identification techniques are chosen. Multivariate static and dynamic
models are used to represent the market behavior. The steps of the
first stage of SMI, named data preprocessing, are mentioned. Next,
the second stage, which is the model estimation, is considered in more
details. Stepwise linear regression (SWR) is used to determine the
significant cross-effects and the orders of the model polynomials. The
estimates of the model parameters are obtained by a numerically stable
estimator. Real market data is used to analyze SMI performance.
The main conclusion is related to the applicability of multivariate
dynamic models for representation of market systems.
Abstract: Experiments have been carried out at sub-critical
Reynolds number to investigate free-to-roll motions induced by
forebody and/or wings complex flow on a 30° swept back nonslender
wings-slender body-model for static and dynamic (pitch-up)
cases. For the dynamic (pitch-up) case it has been observed that roll
amplitude decreases and lag increases with increase in pitching
speed. Decrease in roll amplitude with increase in pitch rate is
attributed to low disturbing rolling moment due to weaker interaction
between forebody and wing flow components. Asymmetric forebody
vortices dominate and control the roll motion of the model in
dynamic case when non-dimensional pitch rate ≥ 1x10-2.
Effectiveness of the active control scheme utilizing rotating nose with
artificial tip perturbation is observed to be low in the angle of attack
region where the complex flow over the wings has contributions from
both forebody and wings.
Abstract: The present work encounters the solution of the defect identification problem with the use of an evolutionary algorithm combined with a simplex method. In more details, a Matlab implementation of Genetic Algorithms is combined with a Simplex method in order to lead to the successful identification of the defect. The influence of the location and the orientation of the depressed ellipsoidal flaw was investigated as well as the use of different amount of static data in the cost function. The results were evaluated according to the ability of the simplex method to locate the global optimum in each test case. In this way, a clear impression regarding the performance of the novel combination of the optimization algorithms, and the influence of the geometrical parameters of the flaw in defect identification problems was obtained.
Abstract: The object of this paper is to design and analyze a
proportional – integral (PI) control for positive output elementary
super lift Luo converter (POESLLC), which is the start-of-the-art
DC-DC converter. The positive output elementary super lift Luo
converter performs the voltage conversion from positive source
voltage to positive load voltage. This paper proposes a
development of PI control capable of providing the good static and
dynamic performance compared to proportional – integralderivative
(PID) controller. Using state space average method
derives the dynamic equations describing the positive output
elementary super lift luo converter and PI control is designed. The
simulation model of the positive output elementary super lift Luo
converter with its control circuit is implemented in
Matlab/Simulink. The PI control for positive output elementary
super lift Luo converter is tested for transient region, line changes,
load changes, steady state region and also for components
variations.
Abstract: This paper introduces a hand gesture recognition system to recognize real time gesture in unstrained environments. Efforts should be made to adapt computers to our natural means of communication: Speech and body language. A simple and fast algorithm using orientation histograms will be developed. It will recognize a subset of MAL static hand gestures. A pattern recognition system will be using a transforrn that converts an image into a feature vector, which will be compared with the feature vectors of a training set of gestures. The final system will be Perceptron implementation in MATLAB. This paper includes experiments of 33 hand postures and discusses the results. Experiments shows that the system can achieve a 90% recognition average rate and is suitable for real time applications.
Abstract: The main focus of the work was concerned with hydrodynamic and thermal analysis of the plate heat exchanger channel with corrugation patterns suggested to be triangular, sinusoidal, and square corrugation. This study was to numerically model and validate the triangular corrugated channel with dimensions/parameters taken from open literature, and then model/analyze both sinusoidal, and square corrugated channel referred to the triangular model. Initially, 2D modeling with local extensive analysis for triangular corrugated channel was carried out. By that, all local pressure drop, wall shear stress, friction factor, static temperature, heat flux, Nusselt number, and surface heat coefficient, were analyzed to interpret the hydrodynamic and thermal phenomena occurred in the flow. Furthermore, in order to facilitate confidence in this model, a comparison between the values predicted, and experimental results taken from literature for almost the same case, was done. Moreover, a holistic numerical study for sinusoidal and square channels together with global comparisons with triangular corrugation under the same condition, were handled. Later, a comparison between electric, and fluid cooling through varying the boundary condition was achieved. The constant wall temperature and constant wall heat flux boundary conditions were employed, and the different resulted Nusselt numbers as a consequence were justified. The results obtained can be used to come up with an optimal design, a 'compromise' between heat transfer and pressure drop.
Abstract: In this paper we present a new multichannel high
voltage driver box to connect up to six MOEMS mirror devices to it that have resonant and also quasistatically driven actuating electrodes. It is possible to drive all resonant axes synchronously
while the amplitude of them can individually be controlled by separate microcontrollers that also operate the quasistatic axes.
Circuit simulations are compared with the measurements done on the
real system and also show the robust driving performance of a
MOEMS mirror.
Abstract: This paper proposes the application of a hierarchical fuzzy system (HFS) based on multi-input power system stabilizer (MPSS) and also Static Var Compensator (SVC) in multi-machine environment.The number of rules grows exponentially with the number of variables in a conventional fuzzy logic system. The proposed HFS method is developed to solve this problem. To reduce the number of rules the HFS consists of a number of low-dimensional fuzzy systems in a hierarchical structure. In fact, by using HFS the total number of involved rules increases only linearly with the number of input variables. In the MPSS, to have better efficiency an auxiliary signal of reactive power deviation (ΔQ) is added with ΔP+ Δω input type Power system stabilizer (PSS). Phasor model of SVC is described and used in this paper. The performances of MPSS, Conventional power system stabilizer (CPSS), hierarchical Fuzzy Multi-input Power System Stabilizer (HFMPSS) and the proposed method in damping inter-area mode of oscillation are examined in response to disturbances. By using digital simulations the comparative study is illustrated. It can be seen that the proposed PSS is performing satisfactorily within the whole range of disturbances.
Abstract: This paper presents an algorithm which
combining ant colony optimization in the dynamic
programming for solving a dynamic facility layout problem.
The problem is separated into 2 phases, static and dynamic
phase. In static phase, ant colony optimization is used to find
the best ranked of layouts for each period. Then the dynamic
programming (DP) procedure is performed in the dynamic
phase to evaluate the layout set during multi-period planning
horizon. The proposed algorithm is tested over many
problems with size ranging from 9 to 49 departments, 2 and 4
periods. The experimental results show that the proposed
method is an alternative way for the plant layout designer to
determine the layouts during multi-period planning horizon.
Abstract: The aim of this study was to compare the solubility of selected volatile organic compounds in water and silicon oil using the simple static headspace method. The experimental design allowed equilibrium achievement within 30 – 60 minutes. Infinite dilution activity coefficients and Henry-s law constants for various organics representing esters, ketones, alkanes, aromatics, cycloalkanes and amines were measured at 303K. The measurements were reproducible with a relative standard deviation and coefficient of variation of 1.3x10-3 and 1.3 respectively. The static determined activity coefficients using shaker flasks were reasonably comparable to those obtained using the gas liquid - chromatographic technique and those predicted using the group contribution methods mainly the UNIFAC. Silicon oil chemically known as polydimethysiloxane was found to be better absorbent for VOCs than water which quickly becomes saturated. For example the infinite dilution mole fraction based activity coefficients of hexane is 0.503 and 277 000 in silicon oil and water respectively. Thus silicon oil gives a superior factor of 550 696. Henry-s law constants and activity coefficients at infinite dilution play a significant role in the design of scrubbers for abatement of volatile organic compounds from contaminated air streams. This paper presents the phase equilibrium of volatile organic compounds in very dilute aqueous and polymeric solutions indicating the movement and fate of chemical in air and solvent. The successful comparison of the results obtained here and those obtained using other methods by the same authors and in literature, means that the results obtained here are reliable.
Abstract: Sub-prime mortgage crisis which began in the US is
regarded as the most economic crisis since the Great Depression in the
early 20th century. Especially, hidden problems on efficient operation
of a business were disclosed at a time and many financial institutions
went bankrupt and filed for court receivership. The collapses of
physical market lead to bankruptcy of manufacturing and construction
businesses. This study is to analyze dynamic efficiency of construction
businesses during the five years at the turn of the global financial
crisis. By discovering the trend and stability of efficiency of a
construction business, this study-s objective is to improve
management efficiency of a construction business in the
ever-changing construction market. Variables were selected by
analyzing corporate information on top 20 construction businesses in
Korea and analyzed for static efficiency in 2008 and dynamic
efficiency between 2006 and 2010. Unlike other studies, this study
succeeded in deducing efficiency trend and stability of a construction
business for five years by using the DEA/Window model. Using the
analysis result, efficient and inefficient companies could be figured
out. In addition, relative efficiency among DMU was measured by
comparing the relationship between input and output variables of
construction businesses. This study can be used as a literature to
improve management efficiency for companies with low efficiency
based on efficiency analysis of construction businesses.
Abstract: Researches related to standard product model and
development of neutral manufacturing interfaces for numerical
control machines becomes a significant topic since the last 25 years.
In this paper, a detail description of STEP implementation on turnmill
manufacturing has been discussed. It shows requirements of
information contents from ISO14649 data model. It covers to
describe the design of STEP-NC framework applicable to turn-mill
manufacturing. In the framework, EXPRESS-G and UML modeling
tools are used to depict the information contents of the system and
established the bases of information model requirement. A product
and manufacturing data model applicable for STEP compliant
manufacturing. The next generation turn-mill operations
requirements have been represented by a UML diagram. An object
oriented classes of ISO1449 has been developed on Visual Basic dot
NET platform for binding the static information model represented
by the UML diagram. An architect of the proposed system
implementation has been given on the bases of the design and
manufacturing module of STEP-NC interface established. Finally, a
part 21 file process plan generated for an illustration of turn-mill
components.
Abstract: The malfunction of thermal protection system (TPS) caused by aerodynamic heating is a latent trouble to aircraft structure safety. Accurately predicting the structure temperature field is quite important for the TPS design of hypersonic vehicle. Since Thornton’s work in 1988, the coupled method of aerodynamic heating and heat transfer has developed rapidly. However, little attention has been paid to the influence of structural deformation on aerodynamic heating and structural temperature field. In the flight, especially the long-endurance flight, the structural deformation, caused by the aerodynamic heating and temperature rise, has a direct impact on the aerodynamic heating and structural temperature field. Thus, the coupled interaction cannot be neglected. In this paper, based on the method of static aero-thermo-elasticity, considering the influence of aero-thermo-elasticity deformation, the aerodynamic heating and heat transfer coupled results of hypersonic vehicle wing model were calculated. The results show that, for the low-curvature region, such as fuselage or center-section wing, structure deformation has little effect on temperature field. However, for the stagnation region with high curvature, the coupled effect is not negligible. Thus, it is quite important for the structure temperature prediction to take into account the effect of elastic deformation. This work has laid a solid foundation for improving the prediction accuracy of the temperature distribution of aircraft structures and the evaluation capacity of structural performance.