The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Animesh Kumar - One of the best experts on this subject based on the ideXlab platform.
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SRAM in hold-operation: Modeling the interaction of soft-errors and switching power-supply noise
2012 IEEE International Symposium on Circuits and Systems (ISCAS), 2012Co-Authors: Amrut Kolhapure, Animesh KumarAbstract:SRAM failure-rate, induced by failure mechanisms such as process variations or cosmic neutrons, increases with reduction in the supply-voltage. Thus, appropriate supply-voltage margins must be used to mitigate or control the failure-rate. This work models and analyzes the interaction of two failure-mechanisms in an SRAM cell during the hold-operation (standby): (i) power-supply noise (due to switching at clock-edge) and soft-errors (due to radioactivity). Circuit-level simulations are used to analyze this interaction. The effect of random process-variations is accounted for by Monte-Carlo simulations. An error in stored-bit of SRAM cell is a transient phenomenon. Therefore, transient analysis of soft-error is carried out in the presence of power-supply noise and random process-variations by using circuit-level simulations in the UMC CMOS 90nm technology. A stochastic process based supply-voltage is difficult to model; therefore, a Lower-Envelope of measured supply-voltage from the literature is used as the noisy waveform. The critical-charge, obtained by using injection-current model of Freeman [1], of an SRAM cell is used to calculate the soft-error rate (SER). Simulation results show that the SER depends on the time-average of the noisy supply-voltage and not on its minimum value. The distribution of critical-charge, due to random process-variations, is estimated using simulations.
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ISCAS - SRAM in hold-operation: Modeling the interaction of soft-errors and switching power-supply noise
2012 IEEE International Symposium on Circuits and Systems, 2012Co-Authors: Amrut Kolhapure, Animesh KumarAbstract:SRAM failure-rate, induced by failure mechanisms such as process variations or cosmic neutrons, increases with reduction in the supply-voltage. Thus, appropriate supply-voltage margins must be used to mitigate or control the failure-rate. This work models and analyzes the interaction of two failure-mechanisms in an SRAM cell during the hold-operation (standby): (i) power-supply noise (due to switching at clock-edge) and soft-errors (due to radioactivity). Circuit-level simulations are used to analyze this interaction. The effect of random process-variations is accounted for by Monte-Carlo simulations. An error in stored-bit of SRAM cell is a transient phenomenon. Therefore, transient analysis of soft-error is carried out in the presence of power-supply noise and random process-variations by using circuit-level simulations in the UMC CMOS 90nm technology. A stochastic process based supply-voltage is difficult to model; therefore, a Lower-Envelope of measured supply-voltage from the literature is used as the noisy waveform. The critical-charge, obtained by using injection-current model of Freeman [1], of an SRAM cell is used to calculate the soft-error rate (SER). Simulation results show that the SER depends on the time-average of the noisy supply-voltage and not on its minimum value. The distribution of critical-charge, due to random process-variations, is estimated using simulations.
Carlo Tomasi - One of the best experts on this subject based on the ideXlab platform.
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ICCV - Linear time offline tracking and Lower Envelope algorithms
2011 International Conference on Computer Vision, 2011Co-Authors: Steve Gu, Ying Zheng, Carlo TomasiAbstract:Offline tracking of visual objects is particularly helpful in the presence of significant occlusions, when a frame-by-frame, causal tracker is likely to lose sight of the target. In addition, the trajectories found by offline tracking are typically smoother and more stable because of the global optimization this approach entails. In contrast with previous work, we show that this global optimization can be performed in O(MNT) time for T frames of video at M × N resolution, with the help of the generalized distance transform developed by Felzenszwalb and Huttenlocher [13]. Recognizing the importance of this distance transform, we extend the computation to a more general Lower Envelope algorithm in certain heterogeneous l 1 -distance metric spaces. The generalized Lower Envelope algorithm is of complexity O(MN(M+N)) and is useful for a more challenging offline tracking problem. Experiments show that trajectories found by offline tracking are superior to those computed by online tracking methods, and are computed at 100 frames per second.
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Linear time offline tracking and Lower Envelope algorithms
2011 International Conference on Computer Vision, 2011Co-Authors: Steve Gu, Ying Zheng, Carlo TomasiAbstract:Offline tracking of visual objects is particularly helpful in the presence of significant occlusions, when a frame-by-frame, causal tracker is likely to lose sight of the target. In addition, the trajectories found by offline tracking are typically smoother and more stable because of the global optimization this approach entails. In contrast with previous work, we show that this global optimization can be performed in O(MNT) time for T frames of video at M × N resolution, with the help of the generalized distance transform developed by Felzenszwalb and Huttenlocher [13]. Recognizing the importance of this distance transform, we extend the computation to a more general Lower Envelope algorithm in certain heterogeneous l1-distance metric spaces. The generalized Lower Envelope algorithm is of complexity O(MN(M+N)) and is useful for a more challenging offline tracking problem. Experiments show that trajectories found by offline tracking are superior to those computed by online tracking methods, and are computed at 100 frames per second.
Amrut Kolhapure - One of the best experts on this subject based on the ideXlab platform.
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SRAM in hold-operation: Modeling the interaction of soft-errors and switching power-supply noise
2012 IEEE International Symposium on Circuits and Systems (ISCAS), 2012Co-Authors: Amrut Kolhapure, Animesh KumarAbstract:SRAM failure-rate, induced by failure mechanisms such as process variations or cosmic neutrons, increases with reduction in the supply-voltage. Thus, appropriate supply-voltage margins must be used to mitigate or control the failure-rate. This work models and analyzes the interaction of two failure-mechanisms in an SRAM cell during the hold-operation (standby): (i) power-supply noise (due to switching at clock-edge) and soft-errors (due to radioactivity). Circuit-level simulations are used to analyze this interaction. The effect of random process-variations is accounted for by Monte-Carlo simulations. An error in stored-bit of SRAM cell is a transient phenomenon. Therefore, transient analysis of soft-error is carried out in the presence of power-supply noise and random process-variations by using circuit-level simulations in the UMC CMOS 90nm technology. A stochastic process based supply-voltage is difficult to model; therefore, a Lower-Envelope of measured supply-voltage from the literature is used as the noisy waveform. The critical-charge, obtained by using injection-current model of Freeman [1], of an SRAM cell is used to calculate the soft-error rate (SER). Simulation results show that the SER depends on the time-average of the noisy supply-voltage and not on its minimum value. The distribution of critical-charge, due to random process-variations, is estimated using simulations.
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ISCAS - SRAM in hold-operation: Modeling the interaction of soft-errors and switching power-supply noise
2012 IEEE International Symposium on Circuits and Systems, 2012Co-Authors: Amrut Kolhapure, Animesh KumarAbstract:SRAM failure-rate, induced by failure mechanisms such as process variations or cosmic neutrons, increases with reduction in the supply-voltage. Thus, appropriate supply-voltage margins must be used to mitigate or control the failure-rate. This work models and analyzes the interaction of two failure-mechanisms in an SRAM cell during the hold-operation (standby): (i) power-supply noise (due to switching at clock-edge) and soft-errors (due to radioactivity). Circuit-level simulations are used to analyze this interaction. The effect of random process-variations is accounted for by Monte-Carlo simulations. An error in stored-bit of SRAM cell is a transient phenomenon. Therefore, transient analysis of soft-error is carried out in the presence of power-supply noise and random process-variations by using circuit-level simulations in the UMC CMOS 90nm technology. A stochastic process based supply-voltage is difficult to model; therefore, a Lower-Envelope of measured supply-voltage from the literature is used as the noisy waveform. The critical-charge, obtained by using injection-current model of Freeman [1], of an SRAM cell is used to calculate the soft-error rate (SER). Simulation results show that the SER depends on the time-average of the noisy supply-voltage and not on its minimum value. The distribution of critical-charge, due to random process-variations, is estimated using simulations.
Steve Gu - One of the best experts on this subject based on the ideXlab platform.
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ICCV - Linear time offline tracking and Lower Envelope algorithms
2011 International Conference on Computer Vision, 2011Co-Authors: Steve Gu, Ying Zheng, Carlo TomasiAbstract:Offline tracking of visual objects is particularly helpful in the presence of significant occlusions, when a frame-by-frame, causal tracker is likely to lose sight of the target. In addition, the trajectories found by offline tracking are typically smoother and more stable because of the global optimization this approach entails. In contrast with previous work, we show that this global optimization can be performed in O(MNT) time for T frames of video at M × N resolution, with the help of the generalized distance transform developed by Felzenszwalb and Huttenlocher [13]. Recognizing the importance of this distance transform, we extend the computation to a more general Lower Envelope algorithm in certain heterogeneous l 1 -distance metric spaces. The generalized Lower Envelope algorithm is of complexity O(MN(M+N)) and is useful for a more challenging offline tracking problem. Experiments show that trajectories found by offline tracking are superior to those computed by online tracking methods, and are computed at 100 frames per second.
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Linear time offline tracking and Lower Envelope algorithms
2011 International Conference on Computer Vision, 2011Co-Authors: Steve Gu, Ying Zheng, Carlo TomasiAbstract:Offline tracking of visual objects is particularly helpful in the presence of significant occlusions, when a frame-by-frame, causal tracker is likely to lose sight of the target. In addition, the trajectories found by offline tracking are typically smoother and more stable because of the global optimization this approach entails. In contrast with previous work, we show that this global optimization can be performed in O(MNT) time for T frames of video at M × N resolution, with the help of the generalized distance transform developed by Felzenszwalb and Huttenlocher [13]. Recognizing the importance of this distance transform, we extend the computation to a more general Lower Envelope algorithm in certain heterogeneous l1-distance metric spaces. The generalized Lower Envelope algorithm is of complexity O(MN(M+N)) and is useful for a more challenging offline tracking problem. Experiments show that trajectories found by offline tracking are superior to those computed by online tracking methods, and are computed at 100 frames per second.
Micha Sharir - One of the best experts on this subject based on the ideXlab platform.
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Almost tight upper bounds for Lower Envelopes in higher dimensions
Discrete and Computational Geometry, 1994Co-Authors: Micha SharirAbstract:We consider the problem of bounding the combinatorial complexity of the Lower Envelope ofn surfaces or surface patches ind-space (d?3), all algebraic of constant degree, and bounded by algebraic surfaces of constant degree. We show that the complexity of the Lower Envelope ofn such surface patches isO(nd?1+?), for any ?>0; the constant of proportionality depends on ?, ond, ons, the maximum number of intersections among anyd-tuple of the given surfaces, and on the shape and degree of the surface patches and of their boundaries. This is the first nontrivial general upper bound for this problem, and it almost establishes a long-standing conjecture that the complexity of the Envelope isO(nd-2?q(n)) for some constantq depending on the shape and degree of the surfaces (where ?q(n) is the maximum length of (n, q) Davenport-Schinzel sequences). We also present a randomized algorithm for computing the Envelope in three dimensions, with expected running timeO(n2+?), and give several applications of the new bounds.
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New bounds for Lower Envelopes in three dimensions, with applications to visibility in terrains
Discrete and Computational Geometry, 1994Co-Authors: Dan Halperin, Micha SharirAbstract:We consider the problem of bounding the complexity of the Lower Envelope ofn surface patches in 3-space, all algebraic of constant maximum degree, and bounded by algebraic arcs of constant maximum degree, with the additional property that the interiors of any triple of these surfaces intersect in at most two points. We show that the number of vertices on the Lower Envelope ofn such surface patches is $$O(n^2 \cdot 2^{c\sqrt {\log n} } )$$ , for some constantc depending on the shape and degree of the surface patches. We apply this result to obtain an upper bound on the combinatorial complexity of the "Lower Envelope" of the space of allrays in 3-space that lie above a given polyhedral terrainK withn edges. This Envelope consists of all rays that touch the terrain (but otherwise lie above it). We show that the combinatorial complexity of this ray-Envelope is $$O(n^3 \cdot 2^{c\sqrt {\log n} } )$$ for some constantc; in particular, there are at most that many rays that pass above the terrain and touch it in four edges. This bound, combined with the analysis of de Berget al. [4], gives an upper bound (which is almost tight in the worst case) on the number of topologically different orthographic views of such a terrain.
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FOCS - Almost tight upper bounds for Lower Envelopes in higher dimensions
Proceedings of 1993 IEEE 34th Annual Foundations of Computer Science, 1993Co-Authors: Micha SharirAbstract:We show that the combinatorial complexity of the Lower Envelope of n surfaces or surface patches in d-space (d/spl ges/3), all algebraic of constant maximum degree, and bounded by algebraic surfaces of constant maximum degree, is O(n/sup d-1+/spl epsi//), for any /spl epsi/>0; the constant of proportionality depends on /spl epsi/, d, and the shape and degree of the surface patches and of their boundaries. This is the first nontrivial general upper bound for this problem, and it almost establishes a long-standing conjecture that the complexity of the Envelope is O(n/sup d-2//spl lambda//sub q/(n)) for some constant q depending on the shape and degree of the surfaces (where /spl lambda//sub q/(n) is the maximum length of (n,q) Davenport-Schinzel sequences). We also present a randomized algorithm for computing the Envelope in three dimensions, with expected running time O(n/sup 2+/spl epsi//), and give several applications of the new bounds. >
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Symposium on Computational Geometry - New bounds for Lower Envelopes in three dimensions, with applications to visibility in terrains
Proceedings of the ninth annual symposium on Computational geometry - SCG '93, 1993Co-Authors: Dan Halperin, Micha SharirAbstract:We consider the problem of bounding the complexity of the Lower Envelope of n surface patches in 3-space, all algebraic of constant maximum degree, and bounded by algebraic arcs of constant maximum degree, with the additional property that the interiors of any triple of these surfaces intersect in at most two points. We show that the number of vertices on the Lower Envelope of n such surface patches is O (n2d2c√log n), for some constant c depending on the shape and degree of the surface patches. We apply this result to obtain an upper bound on the combinatorial complexity of the “Lower Envelope” of the space of all rays in 3-space that lie above a given polyhedral terrain K with n edges. This Envelope consists of all rays that touch the terrain (but otherwise lie above it). We show that the combinatorial complexity of this ray-Envelope is O (n2d2c√log n) for some constant c ; in particular, there are at most that many rays that pass above the terrain and touch it in 4 edges. This bound, combined with the analysis of de Berg et al. [2], gives an upper bound (which is almost tight in the worst case) on the number of topologically-different orthographic views of such a terrain.
