This paper deals with the quadratic stability conditions of fuzzy control systems that relax the ... more This paper deals with the quadratic stability conditions of fuzzy control systems that relax the existing conditions reported in the previous literatures. Two new conditions are proposed and shown to be useful in analyzing and designing fuzzy control systems. The first one employs the S-procedure to utilize information regarding the premise parts of the fuzzy systems. The next one enlarges the class of fuzzy control systems, whose stability is ensured by representing the interactions among the fuzzy subsystems in a single matrix and solving it by linear matrix inequality. The relationships between the suggested stability conditions and the conventional well-known stability conditions reported in the previous literatures are also discussed, and it is shown in a rigorous manner that the second condition of this paper includes the conventional conditions. Finally, some examples and simulation results are presented to illustrate the effectiveness of the stability conditions
A new presentation of the $n$-string braid group $B_n$ is studied. Using it, a new solution to th... more A new presentation of the $n$-string braid group $B_n$ is studied. Using it, a new solution to the word problem in $B_n$ is obtained which retains most of the desirable features of the Garside-Thurston solution, and at the same time makes possible certain computational improvements. We also give a related solution to the conjugacy problem, but the improvements in its complexity are not clear at this writing.
Biodiesel produced by the transesterification of vegetable oils (VOs) is a promising alternative ... more Biodiesel produced by the transesterification of vegetable oils (VOs) is a promising alternative fuel to diesel regarding the limited resources of fossil fuel and the environmental concerns. In this work, an environmentally benign process for the production of biodiesel from VOs ...
culture, yield variable differentiation results or are limited to the generation of selected neur... more culture, yield variable differentiation results or are limited to the generation of selected neural subtypes. Here we provide a set of coculture conditions that allows rapid and efficient derivation of most central nervous system phenotypes. The fate of both fertilizationand nuclear transfer-derived ES (ntES) cells was directed selectively into neural stem cells, astrocytes, oligodendrocytes or neurons. Specific differentiation into γ-aminobutyric acid (GABA), dopamine, serotonin or motor neurons was achieved by defining conditions to induce forebrain, midbrain, hindbrain and spinal cord identity. Neuronal function of ES cell-derived dopaminergic neurons was shown in vitro by electron microscopy, measurement of neurotransmitter release and intracellular recording. Furthermore, transplantation of ES and ntES cell-derived dopaminergic neurons corrected the phenotype of a mouse model of Parkinson disease, demonstrating an in vivo application of therapeutic cloning in neural disease.
A new approach to the word and conjugacy problems in the braid groups Abstract A new presentation... more A new approach to the word and conjugacy problems in the braid groups Abstract A new presentation of the n-string braid group B n is studied. Using it, a new solution to the word problem in B n is obtained which retains most of the desirable features of the Garside-Thurston solution, and at the same time makes possible certain computational improvements. We also give a related solution to the conjugacy problem, but the improvements in its complexity are not clear at this writing. * Partially supported by NSF Grant 94-02988. This paper was completed during a visit by the first author to MSRI. She thanks MSRI for its hospitality and partial support, and thanks Barnard College for its support under a Senior Faculty Research Leave. †This work was initiated during the second author's sabbatical visit to Columbia University in 1995-6. He thanks Columbia University for its hospitality during that visit.
In this paper, we propose two time domain formulations, based upon the use of Whitney elements, o... more In this paper, we propose two time domain formulations, based upon the use of Whitney elements, on tetrahedral meshes for solving transient responses of electromagnetic problems. Among the two formulations, one is an implicit unconditionally stable scheme, whereas the other is an explicit scheme which does not involve matrix inversions. Although the implicit scheme results in worse computational complexity. it is extremely appealing for modeling EM problems with fine features. This is because the time step used in the algorithm is determined by accuracy not by stability. Furthermore, we also present in this paper stability analysis using the Z-transform, computational complexity, and several numerical results for the implicit algorithm .
In this paper we are concerned with non-overlapping domain decomposition methods for the second-o... more In this paper we are concerned with non-overlapping domain decomposition methods for the second-order elliptic problems in three-dimensional domains. We develop a new kind of substructuring method, in which one can use an inexact solver both in each subdomain and on each local interface. The main ideas are to decompose the interface space into the sum of small local subspaces and a series of coarse subspaces spanned by constant-like basis functions, and to design a cheap approximate harmonic extension of the constant-like function. It will be shown that the condition number of the preconditioned system grows only as the logarithm of the dimension of the local problem associated with an individual substructure, and is independent of possible jumps of the coefficient in the elliptic equation.
IEEE Transactions on Pattern Analysis and Machine Intelligence, 2004
This paper proposes a novel hybrid genetic algorithm for feature selection. Local search operatio... more This paper proposes a novel hybrid genetic algorithm for feature selection. Local search operations are devised and embedded in hybrid GAs to fine-tune the search. The operations are parameterized in terms of their fine-tuning power, and their effectiveness and timing requirements are analyzed and compared. The hybridization technique produces two desirable effects: a significant improvement in the final performance and the acquisition of subset-size control. The hybrid GAs showed better convergence properties compared to the classical GAs. A method of performing rigorous timing analysis was developed, in order to compare the timing requirement of the conventional and the proposed algorithms. Experiments performed with various standard data sets revealed that the proposed hybrid GA is superior to both a simple GA and sequential search algorithms.
Our previously reported randomized study of patients with untreated, potentially resectable clini... more Our previously reported randomized study of patients with untreated, potentially resectable clinical stage IIIA non-small-cell lung cancer found that patients treated with perioperative chemotherapy and surgery had a significant increase in median survival compared to patients treated with surgery alone. We have now re-analyzed the results of the study with a median time from random allocation to analysis for all patients of 82 months. The increase in survival conferred by perioperative chemotherapy was maintained during the period of extended observation.
This paper deals with the quadratic stability conditions of fuzzy control systems that relax the ... more This paper deals with the quadratic stability conditions of fuzzy control systems that relax the existing conditions reported in the previous literatures. Two new conditions are proposed and shown to be useful in analyzing and designing fuzzy control systems. The first one employs the S-procedure to utilize information regarding the premise parts of the fuzzy systems. The next one enlarges the class of fuzzy control systems, whose stability is ensured by representing the interactions among the fuzzy subsystems in a single matrix and solving it by linear matrix inequality. The relationships between the suggested stability conditions and the conventional well-known stability conditions reported in the previous literatures are also discussed, and it is shown in a rigorous manner that the second condition of this paper includes the conventional conditions. Finally, some examples and simulation results are presented to illustrate the effectiveness of the stability conditions
A new presentation of the $n$-string braid group $B_n$ is studied. Using it, a new solution to th... more A new presentation of the $n$-string braid group $B_n$ is studied. Using it, a new solution to the word problem in $B_n$ is obtained which retains most of the desirable features of the Garside-Thurston solution, and at the same time makes possible certain computational improvements. We also give a related solution to the conjugacy problem, but the improvements in its complexity are not clear at this writing.
Biodiesel produced by the transesterification of vegetable oils (VOs) is a promising alternative ... more Biodiesel produced by the transesterification of vegetable oils (VOs) is a promising alternative fuel to diesel regarding the limited resources of fossil fuel and the environmental concerns. In this work, an environmentally benign process for the production of biodiesel from VOs ...
culture, yield variable differentiation results or are limited to the generation of selected neur... more culture, yield variable differentiation results or are limited to the generation of selected neural subtypes. Here we provide a set of coculture conditions that allows rapid and efficient derivation of most central nervous system phenotypes. The fate of both fertilizationand nuclear transfer-derived ES (ntES) cells was directed selectively into neural stem cells, astrocytes, oligodendrocytes or neurons. Specific differentiation into γ-aminobutyric acid (GABA), dopamine, serotonin or motor neurons was achieved by defining conditions to induce forebrain, midbrain, hindbrain and spinal cord identity. Neuronal function of ES cell-derived dopaminergic neurons was shown in vitro by electron microscopy, measurement of neurotransmitter release and intracellular recording. Furthermore, transplantation of ES and ntES cell-derived dopaminergic neurons corrected the phenotype of a mouse model of Parkinson disease, demonstrating an in vivo application of therapeutic cloning in neural disease.
A new approach to the word and conjugacy problems in the braid groups Abstract A new presentation... more A new approach to the word and conjugacy problems in the braid groups Abstract A new presentation of the n-string braid group B n is studied. Using it, a new solution to the word problem in B n is obtained which retains most of the desirable features of the Garside-Thurston solution, and at the same time makes possible certain computational improvements. We also give a related solution to the conjugacy problem, but the improvements in its complexity are not clear at this writing. * Partially supported by NSF Grant 94-02988. This paper was completed during a visit by the first author to MSRI. She thanks MSRI for its hospitality and partial support, and thanks Barnard College for its support under a Senior Faculty Research Leave. †This work was initiated during the second author's sabbatical visit to Columbia University in 1995-6. He thanks Columbia University for its hospitality during that visit.
In this paper, we propose two time domain formulations, based upon the use of Whitney elements, o... more In this paper, we propose two time domain formulations, based upon the use of Whitney elements, on tetrahedral meshes for solving transient responses of electromagnetic problems. Among the two formulations, one is an implicit unconditionally stable scheme, whereas the other is an explicit scheme which does not involve matrix inversions. Although the implicit scheme results in worse computational complexity. it is extremely appealing for modeling EM problems with fine features. This is because the time step used in the algorithm is determined by accuracy not by stability. Furthermore, we also present in this paper stability analysis using the Z-transform, computational complexity, and several numerical results for the implicit algorithm .
In this paper we are concerned with non-overlapping domain decomposition methods for the second-o... more In this paper we are concerned with non-overlapping domain decomposition methods for the second-order elliptic problems in three-dimensional domains. We develop a new kind of substructuring method, in which one can use an inexact solver both in each subdomain and on each local interface. The main ideas are to decompose the interface space into the sum of small local subspaces and a series of coarse subspaces spanned by constant-like basis functions, and to design a cheap approximate harmonic extension of the constant-like function. It will be shown that the condition number of the preconditioned system grows only as the logarithm of the dimension of the local problem associated with an individual substructure, and is independent of possible jumps of the coefficient in the elliptic equation.
IEEE Transactions on Pattern Analysis and Machine Intelligence, 2004
This paper proposes a novel hybrid genetic algorithm for feature selection. Local search operatio... more This paper proposes a novel hybrid genetic algorithm for feature selection. Local search operations are devised and embedded in hybrid GAs to fine-tune the search. The operations are parameterized in terms of their fine-tuning power, and their effectiveness and timing requirements are analyzed and compared. The hybridization technique produces two desirable effects: a significant improvement in the final performance and the acquisition of subset-size control. The hybrid GAs showed better convergence properties compared to the classical GAs. A method of performing rigorous timing analysis was developed, in order to compare the timing requirement of the conventional and the proposed algorithms. Experiments performed with various standard data sets revealed that the proposed hybrid GA is superior to both a simple GA and sequential search algorithms.
Our previously reported randomized study of patients with untreated, potentially resectable clini... more Our previously reported randomized study of patients with untreated, potentially resectable clinical stage IIIA non-small-cell lung cancer found that patients treated with perioperative chemotherapy and surgery had a significant increase in median survival compared to patients treated with surgery alone. We have now re-analyzed the results of the study with a median time from random allocation to analysis for all patients of 82 months. The increase in survival conferred by perioperative chemotherapy was maintained during the period of extended observation.
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