Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Kim, N." wg kryterium: Autor


Wyświetlanie 1-3 z 3
Tytuł:
Generator split-phase protection
Autorzy:
Kim, S.
Finney, D.
Fischer, N.
Kasztenny, B.
Powiązania:
https://bibliotekanauki.pl/articles/410559.pdf
Data publikacji:
2012
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
protective relaying
stator differential protection
split-phase protection
Opis:
The stator winding of a hydrogenerator is often made up of coils with multiple turns in the same slot. It is therefore possible for faults to develop between adjacent turns on the same phase (turn-toturn faults). These faults cannot be detected by the stator differential protection because there is no difference between the neutral- and terminal-side currents. Split-phase protection, an overcurrent element responding to the difference between the currents in the winding parallel branches, is typically provided to detect these faults. Ideally, the split-phase element should be sensitive enough to detect a single shorted turn. Despite the fact that the current in this turn can be six to seven times the machine nominal current, the current seen by the split-phase protection can be quite small, in the order of one-twentieth of the generator full-load current. In addition, a spurious split-phase current can be measured due to current transformer (CT) errors, saturation during external faults in particular. Therefore, primary considerations in the application of split-phase protection are the method of measuring the difference in the currents between the parallel branches and the proper selection of the CT used for this purpose.
Źródło:
Present Problems of Power System Control; 2012, 2; 5-40
2084-2201
Pojawia się w:
Present Problems of Power System Control
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Error reduction of the Doppler lidar signal using a re-normalization method
Autorzy:
Park, N G
Baik, S H
Park, S K
Kim, D L
Kim, D. H.
Powiązania:
https://bibliotekanauki.pl/articles/173914.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
injection-seeded laser
Doppler lidar
frequency locking
wind lidar
Doppler velocity measurement
Opis:
In this paper, we present a re-normalization method for a Doppler signal of a Doppler lidar system. For the Doppler lidar system, we used an injection-seeded pulsed Nd:YAG laser as a transmitter and an iodine cell as a Doppler frequency discriminator. A frequency locking system that uses the absorption feature of iodine gas is too sensitive to the external or internal noises (iodine cell temperature instability, laser frequency fluctuation, environmental noises, etc.) to maintain its locking point ideally, and this frequency locking error makes the Doppler lidar system acquire the noises as the Doppler frequency shifts. To reduce the Doppler signal error induced by a frequency locking error, we used a re-normalization method by an addition of a laser beam path separated from a transmitter to the Doppler frequency discriminator for re-normalization. In this method, fluctuations of the Doppler signal were reduced using the reference signal. The reduced amount of standard deviation between the Doppler signal and the re-normalization signal was 4.838×10–3 and the Doppler signals showed a 53.3% fluctuation reduction of the averaged error value by this method.
Źródło:
Optica Applicata; 2014, 44, 1; 103-111
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A mixed control chart adapted to the truncated life test based on the Weibull distribution
Autorzy:
Khan, N.
Aslam, M.
Kim, K.-J.
Jun, C. -H.
Powiązania:
https://bibliotekanauki.pl/articles/406432.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
life test
Weibull distribution
attribute chart
binomial distribution
average run length
Opis:
The design of a new mixed attribute control chart adapted to a truncated life test has been pre-sented. It was assumed that the lifetime of a product follows the Weibull distribution and the number of failures was observed using a truncated life test, where the test duration was specified as a fraction of the mean lifespan. The proposed control chart consists of two pairs of control limits based on a binomial distribution and one lower bound. The average run length of the chart was determined for various levels of shift constants and specified parameters. The efficiency of the chart is compared with an existing control chart in terms of the average run length. The application of the proposed chart is discussed with the aid of a simulation study.
Źródło:
Operations Research and Decisions; 2017, 27, 1; 43-55
2081-8858
2391-6060
Pojawia się w:
Operations Research and Decisions
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies