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Review of the Space Mapping Approach to Engineering Optimization and Modeling
 OPTIMIZATION AND ENGINEERING
, 2000
"... We review the Space Mapping (SM) concept and its applications in engineering optimization and modeling. The aim of SM is to avoid computationally expensive calculations encountered in simulating an engineering system. The existence of less accurate but fast physicallybased models is exploited. SM d ..."
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Cited by 16 (4 self)
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We review the Space Mapping (SM) concept and its applications in engineering optimization and modeling. The aim of SM is to avoid computationally expensive calculations encountered in simulating an engineering system. The existence of less accurate but fast physicallybased models is exploited. SM drives the optimization iterates of the timeintensive model using the fast model. Several algorithms have been developed for SM optimization, including the original SM algorithm, Aggressive Space Mapping (ASM), Trust Region Aggressive Space Mapping (TRASM) and Hybrid Aggressive Space Mapping (HASM). An essential subproblem of any SM based optimization algorithm is parameter extraction. The uniqueness of this optimization subproblem has been crucial to the success of SM optimization. Different approaches to enhance the uniqueness are reviewed. We also discuss new developments in Space Mappingbased Modeling (SMM). These include Space Derivative Mapping (SDM), Generalized Space Mapping (GSM) and Space Mappingbased Neuromodeling (SMN). Finally, we address open points for research and future development.
Relaxed Maximum a Posteriori Fault Identification
, 2007
"... We consider the problem of estimating a pattern of faults, represented as a binary vector, from a set of measurements. The measurements can be noise corrupted real values, or quantized versions of noise corrupted signals, including even 1bit (sign) measurements. Maximum a posteriori probability (MA ..."
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Cited by 11 (9 self)
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We consider the problem of estimating a pattern of faults, represented as a binary vector, from a set of measurements. The measurements can be noise corrupted real values, or quantized versions of noise corrupted signals, including even 1bit (sign) measurements. Maximum a posteriori probability (MAP) estimation of the fault pattern leads to a difficult combinatorial optimization problem, so we propose a variation in which an approximate maximum a posteriori probability estimate is found instead, by solving a convex relaxation of the original problem, followed by rounding and simple local optimization. Our method is extremely efficient, and scales to very large problems, involving thousands (or more) possible faults and measurements. Using synthetic examples, we show that the method performs extremely well, both in identifying the true fault pattern, and in identifying an ambiguity group, i.e., a set of alternate fault patterns that explain the observed measurements almost as well as our estimate. 1
Analog testability analysis and fault diagnosis using behavioral modeling
 Proc. IEEE Custom Integrated Circuits Conference
, 1994
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Automatic fault extraction and simulation of layout realistic faults for integrated analogue circuits
, 1995
"... Abstract A comprehensive tool has been implemented for the comparison of different test preparation techniques and target faults. It comprises of the realistic fault characterisation program LIFT that can extract sets of various faults from a given analogue or mixedsignal circuit layout and the au ..."
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Cited by 9 (0 self)
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Abstract A comprehensive tool has been implemented for the comparison of different test preparation techniques and target faults. It comprises of the realistic fault characterisation program LIFT that can extract sets of various faults from a given analogue or mixedsignal circuit layout and the automatic analogue fault simulation program AnaFAULT which can handle arbitrary catastrophic and parametric faults. For a fabricated integrated VCO circuit the capabilities of the tool are demonstrated and simulation results are presented. assumption of the complete set of possible faults taken from the schematic. After the introduction and the stateoftheart, the application procedure of the universal CAT tool within the
Realistic Faults Mapping Scheme for the Fault Simulation of Integrated Analogue CMOS Circuits
 CMOS Circuits“, ITC, Washington DC, Digest of Paper
, 1996
"... common use is the distinction into two (abstract) fault models: A new fault modelling scheme for integrated analogue general the "Single Hard Fault Model (SHFM)" and the CMOS circuits referred to as Local Layout Realistic Fault Mapping is introduced. It is aimed at realistic fault 1 assum ..."
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Cited by 7 (1 self)
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common use is the distinction into two (abstract) fault models: A new fault modelling scheme for integrated analogue general the "Single Hard Fault Model (SHFM)" and the CMOS circuits referred to as Local Layout Realistic Fault Mapping is introduced. It is aimed at realistic fault 1 assumptions prior to the final layout by investigating typical "local" layout structures of analogue designs. Specific defects are assumed and their electrical failure modes are evaluated and mapped onto appropriate model faults. It is shown that some assumed hard faults at the schematic level are unrealistic and unlikely and that new types of fault constellations emerge including multiple or complex faults. Beside the different distribution of faults the overall number of faults decreases whereof additional realistic soft faults emerge. For an operational CMOS amplifier the overall number of 47 single hard faults assumed at schematic level dropped to 27 realistic and likely hard faults. 1 INTRODUCTION C...
Enhancing DesignforTest for Active Analog Filters by Using CLP(R)
 JOURNAL OF ELECTRONIC TESTING
, 1994
"... We describe a computeraided approach to automatic fault isolation in active analog filters which enhances the designfortest (DFT) methodology proposed by Soma (1990). His primary concern was in increased controllability and observability while the fault isolation procedure was sketched only in ge ..."
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Cited by 5 (2 self)
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We describe a computeraided approach to automatic fault isolation in active analog filters which enhances the designfortest (DFT) methodology proposed by Soma (1990). His primary concern was in increased controllability and observability while the fault isolation procedure was sketched only in general terms. We operationalize and extend the DFT methodology by using CLP(R) to model analog circuits and by a modelbased diagnosis approach to implement a diagnostic algorithm. CLP(R) is a logic programming language which combines symbolic and numeric computation. The diagnostic algorithm uses different DFT test modes and results of voltage measurements for different frequencies and computes a set of suspected components. Ranking of suspected components is based on a measure of (normalized) standard deviations from predicted mean values of component parameters. The diagnosis is performed incrementally, in each step reducing the set of potential candidates for the detected fault. Presented case ...
A Virtual TestBench for Analog Circuit Testability Analysis and Fault Diagnosis
, 1998
"... Are fault simulation techniques feasible and effective for fault diagnosis of analog circuits ? In this paper, we investigate these issues via a software tool which can generate testability metrics and diagnostic information for analog circuits represented by SPICE descriptions. This tool, termed th ..."
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Cited by 5 (1 self)
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Are fault simulation techniques feasible and effective for fault diagnosis of analog circuits ? In this paper, we investigate these issues via a software tool which can generate testability metrics and diagnostic information for analog circuits represented by SPICE descriptions. This tool, termed the Virtual TestBench (VTB), incorporates three different simulationbased techniques for fault detection and isolation. The first method is based on the creation of faulttest dependency models, while the other two techniques employ machine learning principles based on the concepts of: (1) Restricted Coloumb Energy (RCE) Neural Networks, and (2) Learning Vector Quantization (LVQ). Whereas the output of the first method can be used for the traditional offline diagnosis, the RCE and LVQ models render themselves more naturally to online monitoring, where measurement data from various sensors is continuously available. Since it is well known that analog faults and test measurements are affecte...
ModelBased Analogue Circuit Diagnosis with CLP(R)
"... Modelbased diagnosis is the activity of locating malfunctioning components of a system solely on the basis of its structure and behavior. Diagnostic systems usually rely on qualitative models and reason by local constraint propagation methods. However, there is a large class of applications where A ..."
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Cited by 5 (5 self)
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Modelbased diagnosis is the activity of locating malfunctioning components of a system solely on the basis of its structure and behavior. Diagnostic systems usually rely on qualitative models and reason by local constraint propagation methods. However, there is a large class of applications where ATMSlike systems or pure logic programs are unpractical since they are unable to solve simultaneous equations. In particular, modeling realvalued system parameters with tolerances requires some degree of numerical processing, and feedback loops in general cannot be resolved by Appears in Proc. 4th Intl. GI Congress (W. Brauer, D. Hernandez, Eds.), pp. 343353, Munchen, October 2324, 1991, SpringerVerlag (IFB 291). local constraint propagation methods. Examples of such systems are analogue circuits, e.g., amplifiers or filters. In the paper we describe the role of Constraint Logic Programs over the domain of reals (CLP(!)) in representing both, qualitative and numerical models. CLP(!)...
EntropyBased Optimum Test Points Selection for Analog Fault Dictionary Techniques
 IEEE Transactions On Instrumentation And Measurement
, 2004
"... Abstract—An efficient method to select an optimum set of test points for dictionary techniques in analog fault diagnosis is proposed. This is done by searching for the minimum of the entropy index based on the available test points. First, the twodimensional integercoded dictionary is constructed ..."
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Cited by 4 (1 self)
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Abstract—An efficient method to select an optimum set of test points for dictionary techniques in analog fault diagnosis is proposed. This is done by searching for the minimum of the entropy index based on the available test points. First, the twodimensional integercoded dictionary is constructed whose entries are measurements associated with faults and test points. The problem of optimum test points selection is, thus, transformed to the selection of the columns that isolate the rows of the dictionary. Then, the likelihood for a column to be chosen based on the size of its ambiguity set is evaluated using the minimum entropy index of test points. Finally, the test point with the minimum entropy index is selected to construct the optimum set of test points. The proposed entropybased method to select a local minimum set of test points is polynomial bounded in computational cost. The comparison between the proposed method and other reported test points selection methods is carried out by statistical experiments. The results indicate that the proposed method more efficiently and more accurately finds the locally optimum set of test points and is practical for large scale analog systems. Index Terms—Analog fault diagnosis, fault dictionary, rough set, test point. I.