Abstract: In this paper, a new automated methodology to detect the optic disc (OD) automatically in retinal images from patients with risk of being affected by Diabetic Retinopathy (DR) and Macular Edema (ME) is presented. The detection procedure comprises two independent methodologies. On one hand, a location methodology obtains a pixel that belongs to the OD using image contrast analysis and structure filtering techniques and, on the other hand, a boundary segmentation methodology estimates a circular approximation of the OD boundary by applying mathematical morphology, edge detection techniques and the Circular Hough Transform. The methodologies were tested on a set of 1200 images composed of 229 retinographies from patients affected by DR with risk of ME, 431 with DR and no risk of ME and 540 images of healthy retinas. The location methodology obtained 98.83% success rate, whereas the OD boundary segmentation methodology obtained good circular OD boundary approximation in 94.58% of cases. The average computational time measured over the total set was 1.67 seconds for OD location and 5.78 seconds for OD boundary segmentation.
Abstract: This presentation narrates the comparative analysis of
the dissolution data nimesulide microparticles prepared with
ethylcellulose, hydroxypropyl methylcellulose, chitosan and
Poly(D,L-lactide-co-glycolide) as polymers. The analysis of release
profiles showed that the variations noted in the release behavior of
nimesulide from various microparticulate formulations are due to the
nature of used polymer. In addition, maximum retardation in the
nimesulide release was observed with HPMC (floating particles).
Thus HPMC miacroparticles may be preferably employed for
sustained release dosage form development.
Abstract: This paper considers the design of a motion planner
that will simultaneously accomplish control and motion planning of a
n-link nonholonomic mobile manipulator, wherein, a n-link
holonomic manipulator is coupled with a nonholonomic mobile
platform, within an obstacle-ridden environment. This planner,
derived from the Lyapunov-based control scheme, generates
collision-free trajectories from an initial configuration to a final
configuration in a constrained environment cluttered with stationary
solid objects of different shapes and sizes. We demonstrate the
efficiency of the control scheme and the resulting acceleration
controllers of the mobile manipulator with results through computer
simulations of an interesting scenario.
Abstract: A new design approach for three-stage operational
amplifiers (op-amps) is proposed. It allows to actually implement a
symmetrical push-pull class-AB amplifier output stage for wellestablished
three-stage amplifiers using a feedforward
transconductance stage. Compared with the conventional design
practice, the proposed approach leads to a significant
improvement of the symmetry between the positive and the
negative op-amp step response, resulting in similar values of the
positive/negative settling time. The new approach proves to be very
useful in order to fully exploit the potentiality allowed by the op-amp
in terms of speed performances. Design examples in a commercial
0.35-μm CMOS prove the effectiveness of theproposed strategy.
Abstract: The main objectives of this study were to identify
attributes that influence customer satisfaction and determine their
relationships with customer satisfaction. The variables included in
this research are place/ambience, food quality and service quality as
independent variables and customer satisfaction as the dependent
variable. A survey questionnaire which consisted of three parts to
measure demographic factors, independent variables, and dependent
variables was constructed based on items determined by past
research. 149 respondents from one of the well known hotel in Kuala
Lumpur, MALAYSIA were selected as a sample. Psychometric
testing was conducted to determine the reliability and validity of the
questionnaire. From the findings, there were positive significant
relationship between place/ambience (r=0.563**, p=0.000) and
service quality (r=0.544**, p=0.000) with customer satisfaction.
However, although relationship between food quality and customer
satisfaction was significant, it was in the negative direction (r=-
0.268**, p=0.001). New findings were discovered after conducting
this research and previous research findings were strengthened by the
results of this research. Future researchers could concentrate on
determining attributes that influence customer satisfaction when
cost/price is not a factor and reasons for place/ambience is currently
becoming the leading factor in determining customer satisfaction.
Abstract: The strengthening of competitive advantage combined with the transformation of business strategy is necessary for the company to succeed in the time of market changes. And in this sense the innovation activities of the firm are exactly significanting. Virtual firms are a specific form of enterprise in which we can't suppose all regularities obtaining in other forms. The aim of the paper is to evaluate factors influencing the innovation activity of virtual firm with the determination of their importance and influences on the basis of selected metrics.
Abstract: In this paper, different nonlinear dynamics analysis techniques are employed to unveil the rich nonlinear phenomena of the electromagnetic system. In particular, bifurcation diagrams, time responses, phase portraits, Poincare maps, power spectrum analysis, and the construction of basins of attraction are all powerful and effective tools for nonlinear dynamics problems. We also employ the method of Lyapunov exponents to show the occurrence of chaotic motion and to verify those numerical simulation results. Finally, two cases of a chaotic electromagnetic system being effectively controlled by a reference signal or being synchronized to another nonlinear electromagnetic system are presented.
Abstract: In this work we report the recent progresses that have been achieved by our group in the last half decade on the field of computational proteomics. Specifically, we discuss the application of Molecular Dynamics Simulations and Electronic Structure Calculations in drug design, in the clarification of the structural and dynamic properties of proteins and enzymes and in the understanding of the catalytic and inhibition mechanism of cancer-related enzymes. A set of examples illustrate the concepts and help to introduce the reader into this important and fast moving field.
Abstract: Dehydration behavior gives a hint about thermal properties of materials. It is important for the usage areas and transportation of minerals. Magnesium borates can be used as additive materials in areas such as in the production of superconducting materials, in the composition of detergents, due to the content of boron in the friction-reducing additives in oils and insulating coating compositions due to their good mechanic and thermal properties.
In this study, thermal dehydration behavior of admontite (MgO(B2O3)3.7(H2O)), which is a kind of magnesium borate mineral, is experimented by microwave energy at 360W. Structure of admontite is suitable for the investigation of dehydration behavior by microwave because of its seven moles of crystal water. It is seen that admontite lost its 28.7% of weight at the end of the 120 minutes heating in microwave furnace.
Abstract: In general, reports are a form of representing data in
such way that user gets the information he needs. They can be built in
various ways, from the simplest (“select from") to the most complex
ones (results derived from different sources/tables with complex
formulas applied). Furthermore, rules of calculations could be written
as a program hard code or built in the database to be used by dynamic
code. This paper will introduce two types of reports, defined in the
DB structure. The main goal is to manage calculations in optimal
way, keeping maintenance of reports as simple and smooth as
possible.
Abstract: The novelty proposed in this study is twofold and consists in the developing of a new color similarity metric based on the human visual system and a new color indexing based on a textual approach. The new color similarity metric proposed is based on the color perception of the human visual system. Consequently the results returned by the indexing system can fulfill as much as possibile the user expectations. We developed a web application to collect the users judgments about the similarities between colors, whose results are used to estimate the metric proposed in this study. In order to index the image's colors, we used a text indexing engine to facilitate the integration of visual features in a database of text documents. The textual signature is build by weighting the image's colors in according to their occurrence in the image. The use of a textual indexing engine, provide us a simple, fast and robust solution to index images. A typical usage of the system proposed in this study, is the development of applications whose data type is both visual and textual. In order to evaluate the proposed method we chose a price comparison engine as a case of study, collecting a series of commercial offers containing the textual description and the image representing a specific commercial offer.
Abstract: According to Rostler method (ASTM D 2006), saturates content of bitumen is determined based on its reactivity to sulphuric acid. While Corbett method (ASTM D 4124) based on its polarity level. This paper presents results from the study on the effect of saturates content determined by two different fractionation methods on the rheological and aging characteristics of bitumen. The result indicated that the increment of saturates content tended to reduce all the rheological characteristics concerned. Bitumen became less elastic, less viscous, and less resistant to plastic deformation, but became more resistant to fatigue cracking. After short and long term aging process, the treatment effect coefficients of saturates decreased, saturates became thicker due to aging process. This study concludes that saturates is not really stable or reactive in aging process. Therefore, the reactivity of saturates should be considered in bitumen aging index
Abstract: Economic models are complex dynamic systems with a lot of uncertainties and fuzzy data. Conventional modeling approaches using well known methods and techniques cannot provide realistic and satisfactory answers to today-s challenging economic problems. Qualitative modeling using fuzzy logic and intelligent system theories can be used to model macroeconomic models. Fuzzy Cognitive maps (FCM) is a new method been used to model the dynamic behavior of complex systems. For the first time FCMs and the Mamdani Model of Intelligent control is used to model macroeconomic models. This new model is referred as the Mamdani Rule-Based Fuzzy Cognitive Map (MBFCM) and provides the academic and research community with a new promising integrated advanced computational model. A new economic model is developed for a qualitative approach to Macroeconomic modeling. Fuzzy Controllers for such models are designed. Simulation results for an economic scenario are provided and extensively discussed
Abstract: This paper presents a new approach in the identification of the quadrotor dynamic model using a black-box system for identification. Also the paper considers the problems which appear during the identification in the closed-loop and offers a technical solution for overcoming the correlation between the input noise present in the output
Abstract: Exchange algorithm with constraints on magnitude and phase error separately in new way is presented in this paper. An important feature of the algorithms presented in this paper is that they allow for design constraints which often arise in practical filter design problems. Meeting required minimum stopband attenuation or a maximum deviation from the desired magnitude and phase responses in the passbands are common design constraints that can be handled by the methods proposed here. This new algorithm may have important advantages over existing technique, with respect to the speed and stability of convergence, memory requirement and low ripples.
Abstract: Many problems in computer vision and image
processing present potential for parallel implementations through one
of the three major paradigms of geometric parallelism, algorithmic
parallelism and processor farming. Static process scheduling
techniques are used successfully to exploit geometric and algorithmic
parallelism, while dynamic process scheduling is better suited to
dealing with the independent processes inherent in the process
farming paradigm. This paper considers the application of parallel or
multi-computers to a class of problems exhibiting spatial data
characteristic of the geometric paradigm. However, by using
processor farming paradigm, a dynamic scheduling technique is
developed to suit the MIMD structure of the multi-computers. A
hybrid scheme of scheduling is also developed and compared with
the other schemes. The specific problem chosen for the investigation
is the Hough transform for line detection.
Abstract: In this study, a comparison of two control methods,
Proportional Control (PC) and Fuzzy Logic Control (FLC), which
have been used to develop an ideal thermoelectric renal hypothermia
system in order to use in renal surgery, has been carried out. Since
the most important issues in long-lasting parenchymatous renal
surgery are to provide an operation medium free of blood and to
prevent renal dysfunction in the postoperative period, control of the
temperature has become very important in renal surgery. The final
product is seriously affected from the changes in temperature,
therefore, it is necessary to reach some desired temperature points
quickly and avoid large overshoot. PIC16F877 microcontroller has
been used as controller for both of these two methods. Each control
method can simply ensure extra renal hypothermia in the targeted
way. But investigation of advantages and disadvantages of every
control method to each other is aimed and carried out by the
experimental implementations. Shortly, investigation of the most
appropriate method to use for development of system and that can be
applied to people safely in the future, has been performed. In this
sense, experimental results show that fuzzy logic control gives out
more reliable responses and efficient performance.
Abstract: Natural language processing systems pose a unique
challenge for software architectural design as system complexity has
increased continually and systems cannot be easily constructed from
loosely coupled modules. Lexical, syntactic, semantic, and pragmatic
aspects of linguistic information are tightly coupled in a manner that
requires separation of concerns in a special way in design,
implementation and maintenance. An aspect oriented software
architecture is proposed in this paper after critically reviewing
relevant architectural issues. For the purpose of this paper, the
syntactic aspect is characterized by an augmented context-free
grammar. The semantic aspect is composed of multiple perspectives
including denotational, operational, axiomatic and case frame
approaches. Case frame semantics matured in India from deep
thematic analysis. It is argued that lexical, syntactic, semantic and
pragmatic aspects work together in a mutually dependent way and
their synergy is best represented in the aspect oriented approach. The
software architecture is presented with an augmented Unified
Modeling Language.
Abstract: In data mining, the association rules are used to search
for the relations of items of the transactions database. Following the
data is collected and stored, it can find rules of value through
association rules, and assist manager to proceed marketing strategy
and plan market framework. In this paper, we attempt fuzzy partition
methods and decide membership function of quantitative values of
each transaction item. Also, by managers we can reflect the
importance of items as linguistic terms, which are transformed as
fuzzy sets of weights. Next, fuzzy weighted frequent pattern growth
(FWFP-Growth) is used to complete the process of data mining. The
method above is expected to improve Apriori algorithm for its better
efficiency of the whole association rules. An example is given to
clearly illustrate the proposed approach.
Abstract: The characterization and modeling of the dynamic
behavior of many built-up structures under vibration conditions is still
a subject of current research. The present study emphasizes the
theoretical investigation of slip damping in layered and jointed
welded cantilever structures using finite element approach.
Application of finite element method in damping analysis is relatively
recent, as such, some problems particularly slip damping analysis has
not received enough attention. To validate the finite element model
developed, experiments have been conducted on a number of mild
steel specimens under different initial conditions of vibration. Finite
element model developed affirms that the damping capacity of such
structures is influenced by a number of vital parameters such as;
pressure distribution, kinematic coefficient of friction and micro-slip
at the interfaces, amplitude, frequency of vibration, length and
thickness of the specimen. Finite element model developed can be
utilized effectively in the design of machine tools, automobiles,
aerodynamic and space structures, frames and machine members for
enhancing their damping capacity.