Abstract: The prediction of long-term deformations of concrete and reinforced concrete structures has been a field of extensive research and several different creep models have been developed so far. Most of the models were developed for constant concrete stresses, thus, in case of varying stresses a specific superposition principle or time-integration, respectively, is necessary. Nowadays, when modeling concrete creep the engineering focus is rather on the application of sophisticated time-integration methods than choosing the more appropriate creep model. For this reason, this paper presents a method to quantify the uncertainties of creep prediction originating from the selection of creep models or from the time-integration methods. By adapting variance based global sensitivity analysis, a methodology is developed to quantify the influence of creep model selection or choice of time-integration method. Applying the developed method, general recommendations how to model creep behavior for varying stresses are given.
Abstract: A new power regulator controller with multiple-access
PID compensator is proposed, which can achieve a minimum memory
requirement for fully table look-up. The proposed regulator controller
employs hysteresis comparators, an error process unit (EPU) for
voltage regulation, a multiple-access PID compensator and a lowpower-
consumption digital PWM (DPWM). Based on the multipleaccess
mechanism, the proposed controller can alleviate the penalty of
large amount of memory employed for fully table look-up based PID
compensator in the applications of power regulation. The proposed
controller has been validated with simulation results.
Abstract: Hybrid algorithm is the hot issue in Computational
Intelligence (CI) study. From in-depth discussion on Simulation
Mechanism Based (SMB) classification method and composite patterns,
this paper presents the Mamdani model based Adaptive Neural
Fuzzy Inference System (M-ANFIS) and weight updating formula in
consideration with qualitative representation of inference consequent
parts in fuzzy neural networks. M-ANFIS model adopts Mamdani
fuzzy inference system which has advantages in consequent part.
Experiment results of applying M-ANFIS to evaluate traffic Level
of service show that M-ANFIS, as a new hybrid algorithm in computational
intelligence, has great advantages in non-linear modeling,
membership functions in consequent parts, scale of training data and
amount of adjusted parameters.
Abstract: Interactive CAD systems have to allocate and
deallocate memory frequently. Frequent memory allocation and
deallocation can play a significant role in degrading application
performance. An application may use memory in a very specific way
and pay a performance penalty for functionality it does not need. We
could counter that by developing specialized memory managers.
Abstract: Because of the reservoir effect, dynamic analysis of concrete dams is more involved than other common structures. This problem is mostly sourced by the differences between reservoir water, dam body and foundation material behaviors. To account for the reservoir effect in dynamic analysis of concrete gravity dams, two methods are generally employed. Eulerian method in reservoir modeling gives rise to a set of coupled equations, whereas in Lagrangian method, the same equations for dam and foundation structure are used. The Purpose of this paper is to evaluate and study possible advantages and disadvantages of both methods. Specifically, application of the above methods in the analysis of dam-foundationreservoir systems is leveraged to calculate the hydrodynamic pressure on dam faces. Within the frame work of dam- foundationreservoir systems, dam displacement under earthquake for various dimensions and characteristics are also studied. The results of both Lagrangian and Eulerian methods in effects of loading frequency, boundary condition and foundation elasticity modulus are quantitatively evaluated and compared. Our analyses show that each method has individual advantages and disadvantages. As such, in any particular case, one of the two methods may prove more suitable as presented in the results section of this study.
Abstract: The Minimal Residual (MR) is modified for adaptive
filtering application. Three forms of MR based algorithm are
presented: i) the low complexity SPCG, ii) MREDSI, and iii)
MREDSII. The low complexity is a reduced complexity version of a
previously proposed SPCG algorithm. Approximations introduced
reduce the algorithm to an LMS type algorithm, but, maintain the
superior convergence of the SPCG algorithm. Both MREDSI and
MREDSII are MR based methods with Euclidean direction of search.
The choice of Euclidean directions is shown via simulation to give
better misadjustment compared to their gradient search counterparts.
Abstract: Modular fixtures (MFs) are very important tools in
manufacturing processes in terms of reduction the cost and the
production time. This paper introduces an automated approach for
assembling MFs elements by employing SolidWorks as a powerful
3D CAD software. Visual Basic (VB) programming language was
applied integrating with SolidWorks API (Application programming
interface) functions. This integration allowed creating plug-in file and
generating new menus in the SolidWorks environment. The menus
allow the user to select, insert, and assemble MFs elements.
Abstract: In real-field applications, the correct determination of voice segments highly improves the overall system accuracy and minimises the total computation time. This paper presents reliable measures of speech compression by detcting the end points of the speech signals prior to compressing them. The two different compession schemes used are the Global threshold and the Level- Dependent threshold techniques. The performance of the proposed method is tested wirh the Signal to Noise Ratios, Peak Signal to Noise Ratios and Normalized Root Mean Square Error parameter measures.
Abstract: In this paper, we aim to investigate a new stability analysis for discrete-time switched linear systems based on the comparison, the overvaluing principle, the application of Borne-Gentina criterion and the Kotelyanski conditions. This stability conditions issued from vector norms correspond to a vector Lyapunov function. In fact, the switched system to be controlled will be represented in the Companion form. A comparison system relative to a regular vector norm is used in order to get the simple arrow form of the state matrix that yields to a suitable use of Borne-Gentina criterion for the establishment of sufficient conditions for global asymptotic stability. This proposed approach could be a constructive solution to the state and static output feedback stabilization problems.
Abstract: Facial features are frequently used to represent local
properties of a human face image in computer vision applications. In
this paper, we present a fast algorithm that can extract the facial
features online such that they can give a satisfying representation of a
face image. It includes one step for a coarse detection of each facial
feature by AdaBoost and another one to increase the accuracy of the
found points by Active Shape Models (ASM) in the regions of interest.
The resulted facial features are evaluated by matching with artificial
face models in the applications of physiognomy. The distance measure
between the features and those in the fate models from the database is
carried out by means of the Hausdorff distance. In the experiment, the
proposed method shows the efficient performance in facial feature
extractions and online system of physiognomy.
Abstract: Square pipes (pipes with square cross sections) are
being used for various industrial objectives, such as machine
structure components and housing/building elements. The utilization
of them is extending rapidly and widely. Hence, the out-put of those
pipes is increasing and new application fields are continually
developing.
Due to various demands in recent time, the products have to
satisfy difficult specifications with high accuracy in dimensions. The
reshaping process design of pipes with square cross sections;
however, is performed by trial and error and based on expert-s
experience.
In this paper, a computer-aided simulation is developed based on
the 2-D elastic-plastic method with consideration of the shear
deformation to analyze the reshaping process. Effect of various
parameters such as diameter of the circular pipe and mechanical
properties of metal on product dimension and quality can be
evaluated by using this simulation. Moreover, design of reshaping
process include determination of shrinkage of cross section,
necessary number of stands, radius of rolls and height of pipe at each
stand, are investigated. Further, it is shown that there are good
agreements between the results of the design method and the
experimental results.
Abstract: Malate dehydrogenase-glutamate oxaloacetate
aminotransferase (MDh-GOAT) enzyme complex (the EC) was
isolated and purified from wheat and rise, their some main physicchemical
properties were studied. Michael-s constants of the EC
MDh-GOAT to malate, glutamate and NAD were investigated. This
kinetic results show a high relationship to glutamate. Taking into
account important role of the the EC in catabolism of glutamate – the
central amino acid of a nitric exchange, there is a sharp necessity of
deeper studying of this enzyme complex. Therefore the basic purpose
of the work is studying the basic physical and chemical properties of
this enzyme complex discovered by us, which would be very
important for understanding the mechanisms of reaction catalyzed by
the EC.
Abstract: Aiming at most of the aviation products are facing the problem of fatigue fracture in vibration environment, we makes use of the testing result of a bracket, analysis for the structure with ANSYS-Workbench, predict the life of the bracket by different ways, and compared with the testing result. With the research on analysis methods, make an organic combination of simulation analysis and testing, Not only ensure the accuracy of simulation analysis and life predict, but also make a dynamic supervision of product life process, promote the application of finite element simulation analysis in engineering practice.
Abstract: This is an application research presenting the
improvement of production quality using the six sigma solutions and
the analyses of benefit-cost ratio. The case of interest is the
production of tile-concrete. Such production has faced with the
problem of high nonconforming products from an inappropriate
surface coating and had low process capability based on the strength
property of tile. Surface coating and tile strength are the most critical
to quality of this product. The improvements followed five stages of
six sigma solutions. After the improvement, the production yield was
improved to 80% as target required and the defective products from
coating process was remarkably reduced from 29.40% to 4.09%. The
process capability based on the strength quality was increased from
0.87 to 1.08 as customer oriented. The improvement was able to save
the materials loss for 3.24 millions baht or 0.11 million dollars. The
benefits from the improvement were analyzed from (1) the reduction
of the numbers of non conforming tile using its factory price for
surface coating improvement and (2) the materials saved from the
increment of process capability. The benefit-cost ratio of overall
improvement was high as 7.03. It was non valuable investment in
define, measure, analyses and the initial of improve stages after that
it kept increasing. This was due to there were no benefits in define,
measure, and analyze stages of six sigma since these three stages
mainly determine the cause of problem and its effects rather than
improve the process. The benefit-cost ratio starts existing in the
improve stage and go on. Within each stage, the individual benefitcost
ratio was much higher than the accumulative one as there was an
accumulation of cost since the first stage of six sigma. The
consideration of the benefit-cost ratio during the improvement
project helps make decisions for cost saving of similar activities
during the improvement and for new project. In conclusion, the
determination of benefit-cost ratio behavior through out six sigma
implementation period provides the useful data for managing quality
improvement for the optimal effectiveness. This is the additional
outcome from the regular proceeding of six sigma.
Abstract: The issue of unintentional islanding in PV grid
interconnection still remains as a challenge in grid-connected
photovoltaic (PV) systems. This paper discusses the overview of
popularly used anti-islanding detection methods, practically applied
in PV grid-connected systems. Anti-islanding methods generally can
be classified into four major groups, which include passive methods,
active methods, hybrid methods and communication base methods.
Active methods have been the preferred detection technique over the
years due to very small non-detected zone (NDZ) in small scale
distribution generation. Passive method is comparatively simpler
than active method in terms of circuitry and operations. However, it
suffers from large NDZ that significantly reduces its performance.
Communication base methods inherit the advantages of active and
passive methods with reduced drawbacks. Hybrid method which
evolved from the combination of both active and passive methods
has been proven to achieve accurate anti-islanding detection by many
researchers. For each of the studied anti-islanding methods, the
operation analysis is described while the advantages and
disadvantages are compared and discussed. It is difficult to pinpoint a
generic method for a specific application, because most of the
methods discussed are governed by the nature of application and
system dependent elements. This study concludes that the setup and
operation cost is the vital factor for anti-islanding method selection in
order to achieve minimal compromising between cost and system
quality.
Abstract: Electrospinning is a broadly used technology to obtain
polymeric nanofibers ranging from several micrometers down to
several hundred nanometers for a wide range of applications. It offers
unique capabilities to produce nanofibers with controllable porous
structure. With smaller pores and higher surface area than regular
fibers, electrospun fibers have been successfully applied in various
fields, such as, nanocatalysis, tissue engineering scaffolds, protective
clothing, filtration, biomedical, pharmaceutical, optical electronics,
healthcare, biotechnology, defense and security, and environmental
engineering. In this study, polyurethane nanofibers were obtained
under different electrospinning parameters. Fiber morphology and
diameter distribution were investigated in order to understand them
as a function of process parameters.
Abstract: Different numerical methods are employed and developed for simulating interfacial flows. A large range of applications belong to this group, e.g. two-phase flows of air bubbles in water or water drops in air. In such problems surface tension effects often play a dominant role. In this paper, various models of surface tension force for interfacial flows, the CSF, CSS, PCIL and SGIP models have been applied to simulate the motion of small air bubbles in water and the results were compared and reviewed. It has been pointed out that by using SGIP or PCIL models, we are able to simulate bubble rise and obtain results in close agreement with the experimental data.
Abstract: Shortening of natural resources will impose greater
limitations of electric energy consumption in various fields including
water treatment technologies. Small water treatment installations
supplied with electric energy from solar sources are perfect example of
zero-emission technology. Possibility of solar energy application, as
one of the alternative energy resources for decontamination processes
is strongly dependent on geographical location. Various examples of
solar driven water purification systems are given and design of
solar-water treatment installation based on ozone for the geographical
conditions in Poland are presented.
Abstract: In order to assess optical fiber reliability in different environmental and stress conditions series of testing are performed simulating overlapping of chemical and mechanical controlled varying factors. Each series of testing may be compared using statistical processing: i.e. Weibull plots. Due to the numerous data to treat, a software application has appeared useful to interpret selected series of experiments in function of envisaged factors. The current paper presents a software application used in the storage, modelling and interpretation of experimental data gathered from optical fibre testing. The present paper strictly deals with the software part of the project (regarding the modelling, storage and processing of user supplied data).
Abstract: This paper describes the process used in the
automation of the Maritime UAV commands using the Kinect sensor.
The AR Drone is a Quadrocopter manufactured by Parrot [1] to be
controlled using the Apple operating systems such as iPhones and
Ipads. However, this project uses the Microsoft Kinect SDK and
Microsoft Visual Studio C# (C sharp) software, which are compatible
with Windows Operating System for the automation of the navigation
and control of the AR drone.
The navigation and control software for the Quadrocopter runs on
a windows 7 computer. The project is divided into two sections; the
Quadrocopter control system and the Kinect sensor control system.
The Kinect sensor is connected to the computer using a USB cable
from which commands can be sent to and from the Kinect sensors.
The AR drone has Wi-Fi capabilities from which it can be connected
to the computer to enable transfer of commands to and from the
Quadrocopter.
The project was implemented in C#, a programming language that
is commonly used in the automation systems. The language was
chosen because there are more libraries already established in C# for
both the AR drone and the Kinect sensor.
The study will contribute toward research in automation of
systems using the Quadrocopter and the Kinect sensor for navigation
involving a human operator in the loop. The prototype created has
numerous applications among which include the inspection of vessels
such as ship, airplanes and areas that are not accessible by human
operators.