Faster and simpler online computation of string net frequency

In two areas of major importance to the electric power industry-interconnected system operation and steam-electric energy conversion--on-line computer use has expanded during the past five years to applications of increasing complexity and importance. In systems operation, direct digital control is now in successful operation, and many aspects of system security are now monitored by centralized computers. In generating plants on-line computer use has progressed beyond simple data logging; it currently includes some closed-loop control applications, and will be applied to complete boiler control with assemblies now being installed. Simulation and analysis have played an important role in these advances in the application of on-line digital computers.

As advances in computing power forge ahead at an unparalleled rate, an increasingly compelling question that spans nearly every discipline is how best to exploit these advances. At one extreme, a tempting approach is to throw as much computational power at a problem as possible. Unfortunately, this is rarely a justifiable approach unless one has some theoretical guarantee of the efficacy of the computations. At the other extreme, not taking advantage of available computing power is unnecessarily limiting. In general, it is only through a careful inspection of the strengths and weaknesses of all available approaches that an optimal balance between analysis and computation is achieved. This thesis addresses the delicate interaction between theory and computation in the context of optimal control. An exact solution to the nonlinear optimal control problem is known to be prohibitively difficult, both analytically and computationally. Nevertheless, a number of alternative (suboptimal) approaches have been developed. Many of these techniques approach the problem from an off-line, analytical point of view, designing a controller based on a detailed analysis of the system dynamics. A concept particularly amenable to this point of view is that of a control Lyapunov function. These techniques extend the Lyapunov methodology to control systems. In contrast, so-called receding horizon techniques rely purely on on-line computation to determine a control law. While offering an alternative method of attacking the optimal control problem, receding horizon implementations often lack solid theoretical stability guarantees. In this thesis, we uncover a synergistic relationship that holds between control Lyapunov function based schemes and on-line receding horizon style computation. These connections derive from the classical Hamilton-Jacobi-Bellman and Euler-Lagrange approaches to optimal control. By returning to these roots, a broad class of control Lyapunov schemes are shown to admit natural extensions to receding horizon schemes, benefiting from the performance advantages of on-line computation. From the receding horizon point of view, the use of a control Lyapunov function is a convenient solution to not only the theoretical properties that receding horizon control typically lacks, but also unexpectedly eases many of the difficult implementation requirements associated with on-line computation. After developing these schemes for the unconstrained nonlinear optimal control problem, the entire design methodology is illustrated on a simple model of a longitudinal flight control system. They are then extended to time-varying and input constrained nonlinear systems, offering a promising new paradigm for nonlinear optimal control design.

Comparison of an absolute activity analyzing device with an on-line computer in liquid scintillation counting of single and double labelled samples

Since the original work on the Delphi technique, multiple versions have been developed and used in research and industry; however, very little empirical research has been conducted that evaluates the efficacy of using online computer, Internet, and e-mail applications to facilitate a Delphi method that can be used to validate theoretical models. The purpose of this research was to develop computer, Internet, and e-mail applications to facilitate a modified Delphi technique through which experts provide validation for a proposed conceptual model that describes the information needs for a mass-casualty continuum of care. Extant literature and existing theoretical models provided the basis for model development. Two rounds of the Delphi process were needed to satisfy the criteria for consensus and/or stability related to the constructs, relationships, and indicators in the model. The majority of experts rated the online processes favorably (mean of 6.1 on a seven-point scale). Using online Internet and computer applications to facilitate a modified Delphi process offers much promise for future research involving model building or validation. The online Delphi process provided an effective methodology for identifying and describing the complex series of events and contextual factors that influence the way we respond to disasters.

Recent technological advances have made it possible to support long lifetime and large volume streaming data transmissions in sensor networks. A major challenge is to maximize the lifetime of battery-powered sensors to support such transmissions. Battery, as the power provider of the sensors, therefore emerges as the key factor for achieving high performance in such applications. Recent study in battery technology reveals that the behavior of battery discharging is more complex than we used to think. Battery powered sensors might waste a huge amount of energy if we do not carefully schedule and budget their discharging. In this paper we study the effect of battery behavior on routing for streaming data transmissions in wireless sensor networks. We first give an on-line computable energy model to mathematically model battery discharge behavior. We show that the model can capture and describe battery behavior accurately at low computational complexity and thus is suitable for on-line battery capacity computation. Based on this battery model we then present a battery-aware routing (BAR) protocol to schedule the routing in wireless sensor networks. The routing protocol is sensitive to the battery status of routing nodes and avoids energy loss. We use the battery data from actual sensors to evaluate the performance of our protocol. The results show that the battery-aware protocol proposed in this paper performs well and can save a significant amount of energy compared to existing routing protocols for streaming data transmissions. Network lifetime is also prolonged with maximum data throughput. As far as we know, this is the first work considering battery-awareness with an accurate analytical on-line computable battery model in sensor network routing. We believe the battery model can be used to explore other energy efficient schemes for wireless networks as well.

An on-line interactive computer program is described for calculating the parameters of an articulatory model of the human vocal tract corresponding to measured amplitude spectra of speech sounds. The computational procedure comprises two stages: (1) determination of the poles and zeroes of the amplitude spectrum; (2) calculation of a vocal-tract shape having the computed pole-zero pattern. In the first stage, a match to the input spectrum is synthesized from a predetermined number of resonance curves of individual pole or zero pairs having adjustable frequency and bandwidth values. In the second stage of the computation, the cross-sectional area of the vocal tract and the degree of nasal coupling are iteratively adjusted until a satisfactory match to the pole-zero pattern of the input spectrum is achieved. Specification of the vocal-tract shape in terms of the Fourier coefficients of the logarithmic area function leads to a rapidly converging matching strategy. Results for the analysis of vowel-consonant-vowel sequences are given.

On Line Computer Application in Power System - A Case Study

In this paper, we propose a fast signature scheme which realizes short transmissions and minimal on-line computation. Our scheme would require a modular exponentiation as preprocessing (i.e., off-line computation). However, there exist the following remarkable properties: neither multiplication and modular reduction is used in the actual signature generation (i.e., on-line computation). This means that in the on-line phase, our scheme requires only two operations: hashing and addition. So far, some fast signature schemes with small on-line computation are proposed. However, those schemes require multiplication or modular reduction in the on-line phase. This leads to a large amount of work compared to that of addition. As far as we know, this is the first approach to obtain the fast signature without those two calculus methods.KeywordsHash FunctionSignature SchemeRandom OracleRandom Oracle ModelModular ReductionThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Turing oracle machines, online computing, and three displacements in computability theory

On-line learning performance and computer anxiety measure for unemployed adult novices using a grey relation entropy method

MEASUREMENT OF LUNG VOLUME BY MULTIPLE INDICATOR DILUTION: Testing a Modelled Hypothesis with On-line Computation

In this paper, we propose the Fourier series interpolation (FSI) method for the solution of the SDARE* in which the state dependency of the coefficient matrices is of periodic nature. In particular, we focus on the SDAREs where the system matrix depends on a single state component in a periodic way. The main advantage of the FSI approach is that the Fourier coefficients are computed offline. This in turn results in significant reduction in online computations for the solution of the SDARE. The implementation and performance of the FSI method is explained by considering the dynamical positioning (DP) problem of a ship. This problem has been studied by using the SDARE controller and observer. This requires online computation of the solution of the SDAREs. We show that the FSI method significantly reduces the online computation time in comparison with the MATLAB routine “care” in a situation where online solution of the SDARE is required. The FSI method can be particularly useful in situations involving the systems having small time constants.

A new model for on-line arithmetic with an application to the reciprocal calculation

Nather and Evans (1970) emphasize that merely recording the light curve of an occultation is not enough. The data must be recorded in a form which is convenient for the analysis to be carried out later on. Analog methods of recording merely delay the time at which the record must be measured, usually after it has been digitized in some way. Nather and Evans have used a modified digital multiscaler with 400 storage locations for the observation. The data acquisition to be described here is in principle rather similar to a multiscaler and deserves special attention because it is in practice even more flexible and convenient due to its on-line computer. Our system has been used to measure star occultations (De Vegt and Pansch, 1970) and the Crab pulsar (Høg and Lohsen, 1970) and to sample data from a scanning photometer (Høg, 1969).KeywordsLight CurvePhoton CounterClock PulseDouble StarStrip Chart RecordThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Robust energy-to-peak sideslip angle estimation with applications to ground vehicles