We examine vectors and attitude in Engineering with greater attention to detail than in earlier works on the subject. This tutorial is an expansion of part of a survey of attitude representations. The most salient cha...
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We examine vectors and attitude in Engineering with greater attention to detail than in earlier works on the subject. This tutorial is an expansion of part of a survey of attitude representations. The most salient characteristic of this work is a greater emphasis on the distinction between physical vectors and their representation as column vectors. The need for such a treatment arises most strongly in attitude estimation, but logically, the need is present also in attitude dynamics and control. Attitude is estimated by comparing two different column-vector representations of the same physical vector. Thus, from the beginning, the distinction between physical vectors and column vectors requires explicit treatment in attitude estimation. In works on attitude dynamics and control, however, this distinction is often overlooked or presented only in attitude statics, with the transition to attitude dynamics being made as much through verbal arguments as by mathematical development.
Controls and Operation Aspects of Microgrids. THE ENVIRONMENTAL AND ECONOMICAL BENEFITS OF THE MICROGRID, AND consequently its acceptability and degree of proliferation in the utility power industry, are primarily det...
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Controls and Operation Aspects of Microgrids. THE ENVIRONMENTAL AND ECONOMICAL BENEFITS OF THE MICROGRID, AND consequently its acceptability and degree of proliferation in the utility power industry, are primarily determined by the envisioned controller capabilities and the operational features. Depending on the type and depth of penetration of distributed energy resource (DER) units, load characteristics and power quality constraints, and market participation strategies, the required control and operational strategies of a microgrid can be significantly, and even conceptually, different than those of the conventional power systems.
Van der Pol type nonlinear oscillators are used for the design of a torus knot oscillator. This involves replacing the structurally unstable linear oscillators of previous theories by nonlinear Van der Pol ones that c...
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Van der Pol type nonlinear oscillators are used for the design of a torus knot oscillator. This involves replacing the structurally unstable linear oscillators of previous theories by nonlinear Van der Pol ones that can be designed using an op-amp-realized piecewise-linear negative resistor. The resulting five design cases are then conveniently treated, using piecewise-linear theory, to yield limit cycles from which the torus knots are formed. The resulting equations are used to obtain computer-generated torus knot trajectories.< >
The authors present a novel analytic model for the potential and electron distribution in the channel-depth direction for the buried-channel (BC) MOSFET (metal-oxide-semiconductor field-effect transistor). The purpose...
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The authors present a novel analytic model for the potential and electron distribution in the channel-depth direction for the buried-channel (BC) MOSFET (metal-oxide-semiconductor field-effect transistor). The purpose of the model is to aid in the fundamental physical understanding of the operational modes of the BC-MOSFET and the mechanisms affecting these modes. Using Poisson's equation, individual analytic expressions are formulated to predict the potential distribution and electron concentration profile under conditions of depletion, inversion, pinchoff, and accumulation as a function of the gate bias, substrate bias, and applied channel potential. While the potential distribution in the channel-depth direction enables the band-bending within the device to be visualized, the signal electron concentration profile leads to an easy physical interpretation of the modes of operation and the location of mobile charge relative to the channel surface: this is important for mobility and device speed considerations. In addition, the model can be used for device design.< >
A generalization of the van der Pol oscillator, in which a cubic non-linearity in the restoring force is considered, has been studied. For very small values of the cubic parameter, different chaotic transitions take p...
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A generalization of the van der Pol oscillator, in which a cubic non-linearity in the restoring force is considered, has been studied. For very small values of the cubic parameter, different chaotic transitions take place, via period-doubling, saddle-node bifurcations and crises, which restore the symmetry of the chaotic attractor. For larger values of the parameter a period-adding sequence of saddle-node bifurcations and the scaling laws that rule them are found. When negative values of the cubic parameter are considered, bifurcations via hysteresis following a period-adding sequence are found. Finally, it has been found that there is a strong sensitivity to very small modifications of some system parameters. (C) 1996 Academic Press Limited
A method for reconstructing the electrical conductivity profile of a contrasting object in an embedding medium is applied to the problem of induction logging as it is known in the oil industry. The conductivity of the...
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A method for reconstructing the electrical conductivity profile of a contrasting object in an embedding medium is applied to the problem of induction logging as it is known in the oil industry. The conductivity of the formation and the unknown electromagnetic fields are simultaneously reconstructed in an iterative way using-a conjugate gradient type of algorithm. In the algorithm it is assumed that the conductivity is a positive quantity. This fact, together with the knowledge that the contrasting domain is constrained in some test domain, constitutes the only a priori information about the configuration that is needed. Results of a number of numerical examples are presented which demonstrate the robustness of the present inversion scheme and show that an artificial regularization technique is not needed.
Using a 1 ns pulse from a short-pulse CO 2 laser system, the evolution of the gain in a TEA system was studied during and after amplification. This resulted in a very direct observation of a few relaxation processes. ...
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Using a 1 ns pulse from a short-pulse CO 2 laser system, the evolution of the gain in a TEA system was studied during and after amplification. This resulted in a very direct observation of a few relaxation processes. We estimated the effective intramode relaxation rate constant to be larger than 6 \times 10^{6} torr -1 /s. The Fermi relaxation time constant was found to be 30 ± 7 ns at 760 torr. We conclude that for nanosecond pulse amplification, intramode relaxation cannot be neglected.
Estimators of information theoretic measures, such as entropy and mutual information, are a basic workhorse for many downstream applications in modern data science. State-of-the-art approaches have been either geometr...
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Estimators of information theoretic measures, such as entropy and mutual information, are a basic workhorse for many downstream applications in modern data science. State-of-the-art approaches have been either geometric [nearest neighbor (NN)-based] or kernel-based (with a globally chosen bandwidth). In this paper, we combine both these approaches to design new estimators of entropy and mutual information that outperform the state-of-the-art methods. Our estimator uses local bandwidth choices of k-NN distances with a finite k, independent of the sample size. Such a local and data dependent choice ameliorates boundary bias and improves performance in practice, but the bandwidth is vanishing at a fast rate, leading to a non-vanishing bias. We show that the asymptotic bias of the proposed estimator is universal;it is independent of the underlying distribution. Hence, it can be precomputed and subtracted from the estimate. As a byproduct, we obtain a unified way of obtaining both the kernel and NN estimators. The corresponding theoretical contribution relating the asymptotic geometry of nearest neighbors to order statistics is of independent mathematical interest.
Advocates of Transactive Energy (TE) make arguments for the integration of distributed energy resources (DERs) into a market environment from the standpoint of overall energy economics, customer choice, facilitating t...
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Advocates of Transactive Energy (TE) make arguments for the integration of distributed energy resources (DERs) into a market environment from the standpoint of overall energy economics, customer choice, facilitating technology adoption, and encouraging innovation. At a very high level, this is reasonable given the rapid development and adoption of personalized transactions via the web and mobile computing in many domains and the equally rapid proliferation of DERs, at least in some geographic areas.
As human beings, we share the trait of being able to experience extreme fear A variety of events can bring about this level of distress, some of which occur naturally and others that are caused by human action. One su...
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As human beings, we share the trait of being able to experience extreme fear A variety of events can bring about this level of distress, some of which occur naturally and others that are caused by human action. One such event, terrorism, results from human action. In recent times, there has been a shift from conventional weapons for war and terrorism to a type of weapon of mass destruction (WMD) that includes chemical, biological, radiological, nuclear, and high yield explosives (CBRNE) weapons These types of weapons, in addition to their obvious effects, may be particularly capable of causing widespread fear, confusion, and stress that may alter the long-term health of affected communities and the larger community's sense of well-being.
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