Recent work on representing action and change has introduced high-level action languages which describe the effects of actions as causal laws in a declarative way. Among such action languages, the language A is the fi...
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Recent work on representing action and change has introduced high-level action languages which describe the effects of actions as causal laws in a declarative way. Among such action languages, the language A is the first and the most basic language. In dynamic domains, an agent needs the ability to react against changes of environment and to generate robust plans for a long-term goal, and appropriate representation is necessary for this purpose. In real problems, however, it is difficult to describe complete causal laws for the domain, but it is easier to get observations. In this paper, we propose an algorithm to learn causal laws from an incomplete domain description in the language A, given observations after performing action sequences. Our learning algorithm generates causal laws based on an algorithm to learn finite automata. We also prove the correctness of the learning algorithm. From the result in this work, induction of the effects of actions can now be formally characterized within action languages.
This paper describes a novel approach to motion planning for underactuated surface vessels, which belong to a class of nonholonomic nonlinear systems with drift vector field. To find an admissible trajectory which con...
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ISBN:
(纸本)0889863393
This paper describes a novel approach to motion planning for underactuated surface vessels, which belong to a class of nonholonomic nonlinear systems with drift vector field. To find an admissible trajectory which connects the fixed initial and final configurations, we have employed the well-known input/output (I/O) linearization and continuation method with slight modification. Thereby, all linearly perturbed systems along the trajectories updated iteratively can be made controllable. The convergence of the proposed iterative update algorithm for motion planning is rigorously proved and its practicality is demonstrated through a numerical example.
The authors present a study of the finite word length (FWL) implementation for digital controller structures with sparseness consideration. A closed-loop stability related measure is derived, taking into account the n...
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The authors present a study of the finite word length (FWL) implementation for digital controller structures with sparseness consideration. A closed-loop stability related measure is derived, taking into account the number of trivial elements in a controller realisation. A practical design procedure is presented, which first obtains a controller realisation that maximises a lower bound of the proposed measure, and then uses a stepwise algorithm to make the realisation sparse. Simulation results show that the proposed design procedure yields computationally efficient controller realisations with an enhanced FWL closed-loop stability performance.
This paper describes a novel field weakening technology of IPMM (Interior Permanent Magnet Motor) for the extended torque control capability. The proposed method controls the magnitude of flux according to the speed a...
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This paper describes a novel field weakening technology of IPMM (Interior Permanent Magnet Motor) for the extended torque control capability. The proposed method controls the magnitude of flux according to the speed and dc link voltage without losing the ability to regulate the command torque. The control adjusts the d and q-axis current reference toward the operating point with a reduced field magnitude along the constant torque curve. Moving along the constant torque curve insures proper torque linearity even in the field-weakening region. By combining closed-loop control using the output voltage and feed-forward control with the pre-calculated tables, the proposed strategy can achieve fast dynamic control as well as parameter insensitivity in the field-weakening region. The proposed field weakening algorithm is implemented and tested using both a 6kW IPMM designed for the 42V ISG (Integrated Starter Generator) application and a 70kW IPMM used for the elec.ric vehicle propulsion application. The experimental results are presented herein to validate the steady state and dynamic performance of the proposed algorithm.
In this work, we have characterized permittivity of human epidermis (the epidermis: the outer skin layer) using microwave up to 110GHz. A one mm-diameter coaxial probe was adopted to increase measuring bandwidth as we...
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In this work, we have characterized permittivity of human epidermis (the epidermis: the outer skin layer) using microwave up to 110GHz. A one mm-diameter coaxial probe was adopted to increase measuring bandwidth as well as to enhance the spatial resolution. Pork was used to discriminate the permittivities between muscle tissues and fat tissues. The influence of the sample thickness was also studied. Considering several factors, the permittivity was measured on epidermis of the human palm and the wrist. In addition, a relaxation phenomenon observed in the wrist skin, revealed by Cole-Cole parameters, suggested that it originated from high water content beneath thin epidermis of the wrist skin. A relaxation phenomenon revealed by Cole-Cole parameters was observed in the wrist skin. This explains that high water content cells exist beneath thin epidermis of the wrist skin.
This paper investigates time-invariant linear systems subject to input and state constraints. It is shown that the recoverable region (which is the largest domain of attraction that is theoretically achievable) can be...
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This paper investigates time-invariant linear systems subject to input and state constraints. It is shown that the recoverable region (which is the largest domain of attraction that is theoretically achievable) can be semiglobally stabilized by continuous nonlinear feedbacks while satisfying the constraints. Moreover, a reduction technique is presented which shows, when trying to compute the recoverable region, that we only need to compute the recoverable region for a system of lower dimension which generally leads to a considerable simplification in the computational effort.
This paper presents a new method for elec.rically isolating the released high-aspect ratio single crystal silicon MEMS structures. In this method, horizontal dielec.ric layers are implanted at arbitrary depths in any ...
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This paper presents a new method for elec.rically isolating the released high-aspect ratio single crystal silicon MEMS structures. In this method, horizontal dielec.ric layers are implanted at arbitrary depths in any desired region of a wafer, using the Sacrificial Bulk Micromachining (SBM) process. A z-axis microgyroscope is fabricated by the proposed method. The measured noise-equivalent angular rate resolution is 0.0074°/sec, the input range is larger than ± 50°/sec, and the measured bandwidth is 7.3 Hz. The proposed method achieves elec.rical isolation with excellent mechanical stability, and is free from the footing phenomenon.
A robust, time-dependent stress methodology for investigating "mixed-mode" (simultaneous high JC and high V CB) reliability degradation in advanced SiGe HBTs is introduced. We present comprehensive stress da...
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A robust, time-dependent stress methodology for investigating "mixed-mode" (simultaneous high JC and high V CB) reliability degradation in advanced SiGe HBTs is introduced. We present comprehensive stress data on scaled 120 GHz SiGe HBTs, and use specially designed test structures with variable emitter-to-shallow trench spacing to shed light on the resultant damage mechanisms. We also employ calibrated MEDICI simulations using the hot carrier injection current technique to better understand the damage mechanisms, and conclude by assessing the impact of mixed-mode stress in aggressively scaled 200 GHz SiGe HBTs.
To overcome the time step limitation in fluid simulation of high-density plasma disch.rge, an unconditionally stable algorithm that is applicable to Jtot (= J + 1/4π &partE/&partt) = 0 case is proposed[H. Cho...
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To overcome the time step limitation in fluid simulation of high-density plasma disch.rge, an unconditionally stable algorithm that is applicable to Jtot (= J + 1/4π &partE/&partt) = 0 case is proposed[H. Choe et al., J. Comp. Phys. 170, 550 (2001)]. In this article, we extend the algorithm to Jtot ≠ 0 case. To examine the effectiveness of new algorithm, we applied the new method to Jtot ≠ 0 case. The results indicate that the newly developed algorithm successfully overcome the time step limitation.
In this paper we present evidence of detection of B. subtilis (non-pathogene models for B. anthracis) spores using a real-time, dual QCM (quartz crystal microbalance) immuno-sensing system. Device sensitivity is achie...
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In this paper we present evidence of detection of B. subtilis (non-pathogene models for B. anthracis) spores using a real-time, dual QCM (quartz crystal microbalance) immuno-sensing system. Device sensitivity is achieved through the use of a 10MHz AT-cut quartz crystal operating in an enclosed flowcell. Specificity is maintained through the use of an immuno-sensing layer consisting of monoclonal antibodies specific to a single Bacillus species. The fidelity of both sensing parameters is ensured by the presence in our system of a reference device coated with an antibody that is not specific for the target antigen. Associating the QCM response signature with the specific binding of a particular species of Bacillus spore to an antibody has implications for future identification of pathogenic endospores such as B. anthracis.
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