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Estimation of frequency and its rate of change for applications in power systems
2003 IEEE Power Engineering Society General Meeting (IEEE Cat. No.03CH37491), 2004A new method for estimation of power frequency and its rate of change is presented. Unlike conventional methods which are based on the concept of linearization, the proposed scheme accommodates the inherent nonlinearity of the frequency estimation problem. This makes the method capable of providing a fast and accurate estimate of the frequency when its
H. Karimi +2 more
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IEEE International Conference on Communications, 2005. ICC 2005. 2005, 2005
Digital burst-mode transmission is ordinary in a few wireless communications systems such as satellite time-division multiple access (TDMA) and terrestrial mobile cellular radio. In those situations the received carrier may be affected by non-negligible Doppler shift and Doppler rate due to relative motion between transmitter and receiver.
L. GIUGNO, LUISE, MARCO
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Digital burst-mode transmission is ordinary in a few wireless communications systems such as satellite time-division multiple access (TDMA) and terrestrial mobile cellular radio. In those situations the received carrier may be affected by non-negligible Doppler shift and Doppler rate due to relative motion between transmitter and receiver.
L. GIUGNO, LUISE, MARCO
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Trajectory Sensitivity Analysis of Rate of Change of Frequency Using System Frequency Response Model
2018 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe), 2018This paper provides trajectory frequency sensitivity analysis of a large scale power system deploying its simple and reduced order system frequency response (SFR) under sudden load disturbances. By implementing this simple SFR model the calculation time of the real time simulation is reduced while maintaining the accuracy.
Rasoul Azizipanah-Abarghooee +4 more
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An instrument for the measurement of rate of change of power-system frequencies
Proceedings of the IEE - Part II: Power Engineering, 1950A knowledge of the rate of change of frequency of a supply system is a useful addition to the information generally available in control rooms. At times when the available generating plant is inadequate to meet the prospective peak-demand, it assists in the recognition of critical conditions, and thus enables the necessary action to be taken to meet ...
E. Bradshaw, M.Z. Tanyeloglu
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Implications for the Rate of Change of Frequency on an Isolated Power System
2019 54th International Universities Power Engineering Conference (UPEC), 2019The Irish power system illustrates today the main issues which many power systems need to address from an operations and control viewpoint, i.e. the advent of stochastic generation in the form of wind, solar and wave energy, and the change in the constitution of the electrical loads.
Michael O'Donovan +3 more
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An Improved Under Frequency Load Shedding Scheme Based on Rate of Change of Frequency
2010 International Conference on Electrical and Control Engineering, 2010In allusion to the traditional UFLS scheme's deficiencies of changeless frequency setting value and amount of load shedding of every run, this paper proposes improved UFLS scheme which can alter the frequency setting value of the first run and the amount of load shedding of every run dynamically according to the magnitude of frequency change rate ...
Huilan Jiang +4 more
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International Journal of Epidemiology, 1994
Estimation of the number of women infected during pregnancy with Toxoplasma gondii from seroconversion or seroprevalence data meets with various difficulties. Because of the high risk of transmission of the infection to the fetus such infections are however a major concern in pregnancy-related health planning.The expected annual percentage of pregnant ...
S O, Larsen, M, Lebech
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Estimation of the number of women infected during pregnancy with Toxoplasma gondii from seroconversion or seroprevalence data meets with various difficulties. Because of the high risk of transmission of the infection to the fetus such infections are however a major concern in pregnancy-related health planning.The expected annual percentage of pregnant ...
S O, Larsen, M, Lebech
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Development of a frequency-separated knob with variable change rates by rotation speed
Applied Ergonomics, 2014The principle of frequency separation is a design method to display different information or feedback in accordance with the frequency of interaction between users and systems. This principle can be usefully applied to the design of knobs. Particularly, their rotation speed can be a meaningful criterion for applying the principle.
Huhn, Kim, Dong-Han, Ham
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Audibility of short-duration tone-glides as a function of rate of frequency change
Hearing Research, 1982Thresholds for rising and falling tone-glides were determined against a background of 50-6000 Hz noise at a level of 60 dB re 20 microPa. Glides were centered around 2000 Hz and changed frequencies linearly at rates of 24, 48, 96 and 192 Hz/ms; tone-glide durations were 5, 10, 20 and 40 ms.
J K, Cullen, M J, Collins
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Changes in the frequency power spectrum of fetal heart rate in the course of pregnancy
Prenatal Diagnosis, 2003AbstractObjectiveThe aim of this study was to examine changes in the heart rate variability based on the frequency power spectrum of healthy fetuses during the second and third trimester of pregnancy.MethodsWe analyzed 222 fetal magnetocardiograms recorded in 49 healthy singleton pregnancies between the 16th and 42nd week.
Peter, Van Leeuwen +4 more
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