The Experts below are selected from a list of 2424 Experts worldwide ranked by ideXlab platform
Silvano Colombano - One of the best experts on this subject based on the ideXlab platform.
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a circuit representation technique for automated circuit design
IEEE Transactions on Evolutionary Computation, 1999Co-Authors: Jason D Lohn, Silvano ColombanoAbstract:We present a method of automatically generating circuit designs using evolutionary search and a set of circuit constructing primitives arranged in a linear sequence. This representation has the desirable property that virtually all sets of circuit-constructing primitives result in valid circuit graphs. While this representation excludes certain circuit topologies, it is capable of generating a rich set of them including many of the useful topologies seen in hand-designed circuits. Our system allows circuit size (number of devices), circuit topology, and device values to he evolved. Using a parallel genetic algorithm and circuit simulation software, we present experimental results as applied to three analog filter and two amplifier design tasks. In all tasks, our system is able to generate circuits that achieve the target specifications. Although the evolved circuits exist as software models, detailed examinations of each suggest that they are electrically well behaved and thus suitable for physical implementation. The modest computational requirements suggest that the ability to evolve complex analog circuit representations in software is becoming more approachable on a single Engineering Workstation.
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automated analog circuit sythesis using a linear representation
International Conference on Evolvable Systems, 1998Co-Authors: Jason D Lohn, Silvano ColombanoAbstract:We present a method of evolving analog electronic circuits using a linear representation and a simple unfolding technique. While this representation excludes a large number of circuit topologies, it is capable of constructing many of the useful topologies seen in hand-designed circuits. Our system allows circuit size, circuit topology, and device values to be evolved. Using a parallel genetic algorithm we present initial results of our system as applied to two analog filter design problems. The modest computational requirements of our system suggest that the ability to evolve complex analog circuit representations in software is becoming more approachable on a single Engineering Workstation.
Jason D Lohn - One of the best experts on this subject based on the ideXlab platform.
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a circuit representation technique for automated circuit design
IEEE Transactions on Evolutionary Computation, 1999Co-Authors: Jason D Lohn, Silvano ColombanoAbstract:We present a method of automatically generating circuit designs using evolutionary search and a set of circuit constructing primitives arranged in a linear sequence. This representation has the desirable property that virtually all sets of circuit-constructing primitives result in valid circuit graphs. While this representation excludes certain circuit topologies, it is capable of generating a rich set of them including many of the useful topologies seen in hand-designed circuits. Our system allows circuit size (number of devices), circuit topology, and device values to he evolved. Using a parallel genetic algorithm and circuit simulation software, we present experimental results as applied to three analog filter and two amplifier design tasks. In all tasks, our system is able to generate circuits that achieve the target specifications. Although the evolved circuits exist as software models, detailed examinations of each suggest that they are electrically well behaved and thus suitable for physical implementation. The modest computational requirements suggest that the ability to evolve complex analog circuit representations in software is becoming more approachable on a single Engineering Workstation.
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automated analog circuit sythesis using a linear representation
International Conference on Evolvable Systems, 1998Co-Authors: Jason D Lohn, Silvano ColombanoAbstract:We present a method of evolving analog electronic circuits using a linear representation and a simple unfolding technique. While this representation excludes a large number of circuit topologies, it is capable of constructing many of the useful topologies seen in hand-designed circuits. Our system allows circuit size, circuit topology, and device values to be evolved. Using a parallel genetic algorithm we present initial results of our system as applied to two analog filter design problems. The modest computational requirements of our system suggest that the ability to evolve complex analog circuit representations in software is becoming more approachable on a single Engineering Workstation.
Douglas L Smoot - One of the best experts on this subject based on the ideXlab platform.
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prediction of effluent compositions for fixed bed coal gasifiers
Fuel, 1992Co-Authors: Michael L Hobbs, Predrag T Radulovic, Douglas L SmootAbstract:Abstract A two-zone, well-mixed, partial equilibrium model that provides efficient estimates of fixed bed coal gasifier effluent temperature, tar production and gas composition has been developed and evaluated. The model includes detailed treatment of devolatilization, partial equilibrium of volatile gases, treatment of a large number of gas-phase species, and estimation of tar production with potential for recirculation of effluent products. Predictions have been compared to measured effluent compositions from two large-scale fixed-bed reactors over a wide range of coal types and operating conditions. Model evaluation also includes determination of sensitivity of effluent temperature and composition to model options, model parameters and operational parameters. The model can be used separately or as part of a large process simulator since execution times are on the order of seconds using an Engineering Workstation. Furthermore, the predicted effluent compositions can provide useful initial estimates for one- or two-dimensional fixed-bed models.
Michael L Hobbs - One of the best experts on this subject based on the ideXlab platform.
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prediction of effluent compositions for fixed bed coal gasifiers
Fuel, 1992Co-Authors: Michael L Hobbs, Predrag T Radulovic, Douglas L SmootAbstract:Abstract A two-zone, well-mixed, partial equilibrium model that provides efficient estimates of fixed bed coal gasifier effluent temperature, tar production and gas composition has been developed and evaluated. The model includes detailed treatment of devolatilization, partial equilibrium of volatile gases, treatment of a large number of gas-phase species, and estimation of tar production with potential for recirculation of effluent products. Predictions have been compared to measured effluent compositions from two large-scale fixed-bed reactors over a wide range of coal types and operating conditions. Model evaluation also includes determination of sensitivity of effluent temperature and composition to model options, model parameters and operational parameters. The model can be used separately or as part of a large process simulator since execution times are on the order of seconds using an Engineering Workstation. Furthermore, the predicted effluent compositions can provide useful initial estimates for one- or two-dimensional fixed-bed models.
Kazuo Sumita - One of the best experts on this subject based on the ideXlab platform.
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a full text retrieval system with a dynamic abstract generation function
International ACM SIGIR Conference on Research and Development in Information Retrieval, 1994Co-Authors: Seiji Miike, Etsuo Itoh, Kenji Ono, Kazuo SumitaAbstract:We have developed a Japanese full-text retrieval system named BREVIDOC* that enables the user to specify an area within a text for abstraction and to control the volume of the abstract interactively. This system analyzes a document structure using linguistic knowledge only and thus is domain-independent. In its text structure analysis, the system determines relations among paragraphs and sentences, based on linguistic clues such as connectives, anaphoric expressions, and idiomatic expressions. The system analyzes and stores the text structure in advance so that it can generate an abstract in real time by selecting sentences according to relative importance of rhetorical relations among the sentences. The retrieval system works on an Engineering Workstation.