In reverse engineering one often needs to generate geometrical models of old mechanical parts. Manual redrafting of old products using computer aided design (CAD) software is a laborious procedure. To overcome this pr...
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In reverse engineering one often needs to generate geometrical models of old mechanical parts. Manual redrafting of old products using computer aided design (CAD) software is a laborious procedure. To overcome this problem, an automated procedure is proposed. the proposed approach is based on using clustering to segment the range image of the object and then constructing a solid model using an automated procedure. To demonstrate the feasibility of the proposed method, the model generation for convex planar faceted objects is considered. A generalized version of the adaptive fuzzy c-elliptotype clustering algorithm suitable for higher dimensional data is used to identify the planar facets in noisy range images when the number of facets is unknown.
Fuzzy predictive control integrates conventional model-based predictive control with techniques from fuzzy multicriteria decision making, and translates the goals and the constraints to predictive control in a transpa...
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Fuzzy predictive control integrates conventional model-based predictive control with techniques from fuzzy multicriteria decision making, and translates the goals and the constraints to predictive control in a transparent way. the information regarding the (fuzzy) goals and the (fuzzy) constraints of the control problem is combined by using a decision function from the fuzzy set theory. this paper investigates the use of fuzzy decision making in predictive control and compares the results to those obtained from conventional model-based predictive control. Experiments on a nonminimum phase, unstable linear system and air conditioning system with nonlinear dynamics are studied. It is shown that the performance of the model-based predictive controller can be improved by the use of fuzzy goals and criteria with fuzzy decision-making techniques.
Test concepts mostly refer to the program code and not to models used in earlier stages of the software development process. High-level Petri nets are a widely accepted graphical language for the representation and si...
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Test concepts mostly refer to the program code and not to models used in earlier stages of the software development process. High-level Petri nets are a widely accepted graphical language for the representation and simulation of requirements, analysis and design models. In this paper, a technique is proposed which generates test cases for the validation of high-level Petri nets in a systematic way. Our approach is derived from cause-effect graphs, a concept that was originally developed for testing of program code. However, in our approach the relationship between pre-specified causes and effects is not represented by a Boolean graph, but instead by a Petri net. the test cases are created in a quite efficient way by generating so-called process nets.
this paper focuses on the experiences gained from defining design metrics for SDL and comparing three prediction models for identifying the most fault-prone entities using the defined metrics. three sets of design com...
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ISBN:
(纸本)081868271X
this paper focuses on the experiences gained from defining design metrics for SDL and comparing three prediction models for identifying the most fault-prone entities using the defined metrics. three sets of design complexity metrics for SDL are defined according to two design phases and SDL entity types. Two neural net based prediction models and a model using the hybrid metrics are implemented and compared by a simulation. though the backpropagation model shows the best prediction results, the selection method in hybrid complexity order is expected to have similar performance with some supports. Also two hybrid metric forms (weighted sum and weighted multiplication) are compared and it is shown that two metric forms can be used interchangeably for ordinal purpose.
We address the problem of control relevant process modeling from production data for the N-well reactive ion etching processed by LAM Rainbow Etchers. Due to physical constraints we consider building an empirical neur...
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We address the problem of control relevant process modeling from production data for the N-well reactive ion etching processed by LAM Rainbow Etchers. Due to physical constraints we consider building an empirical neural network model using one lot of data which usually contains 24 wafers. Using the existence result of feedforward networks as universal approximators, we experimentally developed different network structures as models of the etching process under investigation. Our results are built upon extensive simulations on different lots of the process. the same modeling idea is also extended to use the network model to predict the end point detection signal prior for the processing of one wafer.
the characteristics of [110] silicon anisotropic bulk etching for fabrication of comb structure are studied with varied temperature and concentration of aqueous KOH solution the etch rates of [110] and (111) planes in...
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ISBN:
(纸本)0780341929
the characteristics of [110] silicon anisotropic bulk etching for fabrication of comb structure are studied with varied temperature and concentration of aqueous KOH solution the etch rates of [110] and (111) planes increase with increasing temperature but decrease with increasing concentration. the maximum etch rate ratio is above 150 at 45 exact wt.% and 60/spl deg/C of aqueous KOH solution. Surface roughness varies greatly with concentration, and the minimum roughness is observed in an aqueous KOH solution of 41 exact wt.%. the mechanism of beam reduction is also studied and modelled simply. Considering the etching characteristics, comb structure have been fabricated which are 8 /spl mu/m wide, 150 /spl mu/m high and separated by 7 /spl mu/m gaps, using a comb mask pattern 10 /spl mu/m wide with 5 /spl mu/m gaps in 41 exact wt.% aqueous KOH solution at 65/spl deg/C.
the paper presents a passivity framework to analyse the asymptotic stability of zero-steady-state error solutions of fuzzy control systems. Typical two-input-single-output fuzzy, controllers (FC) are considered for wh...
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the paper presents a passivity framework to analyse the asymptotic stability of zero-steady-state error solutions of fuzzy control systems. Typical two-input-single-output fuzzy, controllers (FC) are considered for which we propose a continuous-time single input nonlinear dynamic representation based on a pseudo-derivative of the error. the nonlinear part is a two-input mapping with a set of properties arising from the mini or product-inference rule, as well as properties of the input and output fuzzy sets used. the stability analysis is performed for the class of linear time invariant plant models with PI-like FC, it is based on general results coming from positive real and passive systems, leading to two graphical tests. Hints are given to deal withthe case of PD-like FC.
We present Cartesian granule feature, a new multidimensional feature formed over the cross product of fuzzy partition labels. Traditional fuzzy modelling approaches, mainly use flat features (one dimensional features)...
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We present Cartesian granule feature, a new multidimensional feature formed over the cross product of fuzzy partition labels. Traditional fuzzy modelling approaches, mainly use flat features (one dimensional features) and, consequently suffer from decomposition error when modelling systems where there are dependencies between the input variables. Cartesian granule features help reduce (if not eliminate) the error due to the decompositional usage of features. In the approach taken here, we label the (fuzzy) subsets which partition the various universes and incorporate these labels in the form of Cartesian granules into our modelling process. Fuzzy sets defined in terms of these Cartesian granules, are extracted automatically from statistical data using the theory of mass assignments, and are incorporated into fuzzy rules. Consequently we not only compute with words, we also model with words. Due to the interpolative nature of fuzzy sets, this approach can be used to model both classification and prediction problems. Overall Cartesian granule features incorporated into fuzzy rules yield glass-box models and when demonstrated on the ellipse classification problem yields a classification accuracy of 98%, outperforming standard modelling approaches such as neural networks and the data browser.
Prediction of the next-crossing cell is an important issue for mobility and connection management in wireless radio networks. We propose a new approach to modeling inter-cell user mobility, and develop an optimum self...
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Prediction of the next-crossing cell is an important issue for mobility and connection management in wireless radio networks. We propose a new approach to modeling inter-cell user mobility, and develop an optimum self-learning estimator for trajectory tracking and next-crossing cell prediction. the dynamic states of movement, in terms of speed and position, are obtained by modeling the user's acceleration as a time correlated, semi-Markovian process, and by passing subsequent signal-strength measurements to neighboring base stations through an extended, self-learning Kalman filter. Prediction of next-crossing cell is obtained by evaluating user dynamic states with cell geometry. Analysis and simulation results show that our prediction algorithm is robust in the presence of pass loss, shadow fading, and random movement, being able to predict the position, speed, and direction-of-travel of the mobile user with a high degree accuracy.
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