Informacja

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

Wyszukujesz frazę "error rate" wg kryterium: Temat


Tytuł:
The modification of stepwise multiple procedure
Modyfikacja kroczącej wstępującej procedury testowania wielokrotnego
Autorzy:
Parys, Dariusz
Powiązania:
https://bibliotekanauki.pl/articles/907018.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
multiple testing
familywise error rate
stepdown procedure
Opis:
In this paper we discuss stepdown methods that control the familywise error rate in finite samples. Such methods proceed stagewise by testing an intersection hypothesis without regard to hypotheses previously rejected. However, one cannot always achieve strong control in such a simple manner. By understanding the limitations of this approach in finite samples, we can then see why an asymptotic approach will be valid under fairly weak assumptions. It turns out that a simple monotonicity condition for theoretical critical values allows for some immediate results.
Procedury kroczące w porównaniach wielokrotnych często nie są w stanie zachować silnej kontroli nad błędem rodziny (tzw. familywise errors rate FWE). Prezentujemy tutaj ogólną metodę wnioskowania wielokrotnego opartego na krokach zstępujących i na jej tle proponujemy metodę wykorzystując modyfikację stałych krytycznych, które lepiej sprawują kontrolę nad FWE dla prób skończonych.
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2008, 216
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Modified Holm’s Stepwise Rejective Multiple Test Procedure
Zmodyfikowana wielokrotna procedura testowa kroczącego odrzucenia Holma
Autorzy:
Parys, Dariusz
Powiązania:
https://bibliotekanauki.pl/articles/905696.pdf
Data publikacji:
2006
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
multiple test procedure
stepwise procedure
familywise error rate
Źródło:
Acta Universitatis Lodziensis. Folia Oeconomica; 2006, 196
0208-6018
2353-7663
Pojawia się w:
Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the binary classification problem in discriminant analysis using linear programming methods
Autorzy:
Olusola, Michael O.
Onyeagu, Sydney I.
Powiązania:
https://bibliotekanauki.pl/articles/406591.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
binary classification
discriminant analysis
error rate
hit rate
linear programming
Opis:
This paper is centred on a binary classification problem in which it is desired to assign a new object with multivariate features to one of two distinct populations as based on historical sets of samples from two populations. A linear discriminant analysis framework has been proposed, called the minimised sum of deviations by proportion (MSDP) to model the binary classification problem. In the MSDP formulation, the sum of the proportion of exterior deviations is minimised subject to the group separation constraints, the normalisation constraint, the upper bound constraints on proportions of exterior deviations and the sign unrestriction vis-à-vis the non-negativity constraints. The two-phase method in linear programming is adopted as a solution technique to generate the discriminant function. The decision rule on group-membership prediction is constructed using the apparent error rate. The performance of the MSDP has been compared with some existing linear discriminant models using a previously published dataset on road casualties. The MSDP model was more promising and well suited for the imbalanced dataset on road casualties.
Źródło:
Operations Research and Decisions; 2020, 30, 1; 119-130
2081-8858
2391-6060
Pojawia się w:
Operations Research and Decisions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Implementation of C-PolSK Modulation in FSO Network and Analysis of its Atmospheric Performance
Autorzy:
Chattopadhyay, Diptangshu
Bharti, Manisha
Powiązania:
https://bibliotekanauki.pl/articles/309433.pdf
Data publikacji:
2019
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
attenuation
bit error rate
circular polarization shift keying
quality factor
Opis:
Free Space Optical (FSO) communication is a quickly developing technology that is designed to handle high data rates while maintaining a good quality factor (Q-factor). Many novel techniques have been implemented to cope with atmospheric attenuating factors, such as fog and rain. Here, we have introduced circular polarization shift keying (C-PolSK) modulation to produce a stable and uniform light beam. The plane of polarized light keeps rotating along with the propagation vector, which helps reduce phase variations and cross-channel effects. C-PolSK provides higher penetrating power and attenuation resistance over linear polarization shift keying (L-PolSK). Two different C-PolSK models have been proposed and graphical comparisons, relying on such parameters as Q-factor, transmission distance and inputoutput power, have been made. The cases of moderate fog and rain attenuation are taken to verify the model’s efficiency. Polarized light is split into two orthogonal components and then modulated using the Mach-Zehnder modulator. One of the models also employs the principle of orthogonal differential phase shifting. Eye diagrams have been provided to verify the bit error rate (BER). The orthogonal differential phase shifted C-PolSK model proves to be the most suitable implementation prototype.
Źródło:
Journal of Telecommunications and Information Technology; 2019, 4; 43-49
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Transmitter Inclination Angle Characteristics for Underwater Optical Wireless Communication in a Variety of APD Detectors
Autorzy:
Mazin, Ali A. Ali
Powiązania:
https://bibliotekanauki.pl/articles/1192197.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Communications
Underwater Optical Communications
Avalanche Photodiode
Bit Error Rate
Channel Capacity
Opis:
In this paper, the performance of an underwater optical wireless communications system is theoretically analyzed, using 4-PPM modulation technique and an avalanche photodiodes APD receiver over underwater environment channels. Based on the line of sight (LOS) geometrical model for optical beam propagation horizontally on an underwater medium and combined with signal to noise ratio model for Si, Ge and InGaAs APD and BER; then the impacts of the distance of transmission, power of the transmitter under Jerlov water types (I, IA, IB) are analyzed. The characteristics of bit error rate BER and channel capacity for 4-PPM optical modulation technique are studied under different APD detector and Jerlov water types. Simulation results indicate that the performance of PPM and Jerlov type (I) are more suited for an underwater optical wireless communication. On the other hand, we discuss the suitability of avalanche photodiodes under this modulation technique, where the photodiode Si APD has more advantage compared with the other detectors when used as a receiver in an underwater optical communication.
Źródło:
World Scientific News; 2016, 45, 2; 355-372
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance Analysis of Hybrid Phase Shift Keying over Generalized Nakagami Fading Channels
Autorzy:
Youssuf, M.
Abdelmageed, M. Z.
Powiązania:
https://bibliotekanauki.pl/articles/308527.pdf
Data publikacji:
2010
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
bit error rate
hybrid phase shift keying
quadrature phase shift keying
Opis:
In addition to the benefits of hybrid phase shift keying (HPSK) modulation in reducing the peak to average power ratio of the transmitted signal to reduce the zero cross- ings and the 0?-degree phase transmissions, HPSK enhances the bit error rate (BER) measure of the signal performance. The constellation of the HPSK is analyzed, and an expression for the conditional probability of HPSK modulation over additive white Gaussian noise (AWGN) is derived. This BER measure of HPSK is shown to outperform quadrature phase shift keying (QPSK) modulation. HPSK performance through Nakagami - m fading channel is also considered.
Źródło:
Journal of Telecommunications and Information Technology; 2010, 3; 77-82
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hybrid PAPR reduction schemes for different OFDM-based VLC systems
Autorzy:
El-Ganiny, Mohamed Y.
Khalaf, Ashraf A. M.
Hussein, Aziza I.
Hamed, Hesham F. A.
Powiązania:
https://bibliotekanauki.pl/articles/2174839.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
visible light communication
peak-to-average power ratio
bit error rate
Opis:
Orthogonal frequency division multiplexing has been widely used in many radio frequency wireless communication standards as a preferable multicarrier modulation scheme. The modulated signals of a conventional orthogonal frequency division multiplexing system are complex and bipolar. In intensity-modulated direct detection optical wireless communications, transmitted signals should be real and unipolar due to non-coherent emissions of an optical light emitting diode. In this paper, different hybrid optical systems have been proposed to satisfy real and unipolar signals. Peak-to-average power ratio is one of the biggest challenges for orthogonal frequency division multiplexing-based visible light communications. They are based on a combination of non-linear companding techniques with spreading or precoding techniques. Simulation evaluation is performed under direct current-biased optical orthogonal frequency division multiplexing, asymmetrically clipped optical orthogonal frequency division multiplexing, and Flip-orthogonal frequency division multiplexing systems in terms of peak-to-average power ratio, bit error rate, and spectral efficiency. The proposed schemes are investigated to determine a scheme with a low peak-to-average power ratio and an acceptable bit error rate. MATLABTM software has been successfully used to show the validity of the proposed schemes.
Źródło:
Opto-Electronics Review; 2022, 30, 3; art. no. e141951
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hybrid PAPR reduction schemes for different OFDM-based VLC systems
Autorzy:
El-Ganiny, Mohamed Y.
Khalaf, Ashraf A. M.
Hussein, Aziza I.
Hamed, Hesham F. A.
Powiązania:
https://bibliotekanauki.pl/articles/2174840.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
visible light communication
peak-to-average power ratio
bit error rate
Opis:
Orthogonal frequency division multiplexing has been widely used in many radio frequency wireless communication standards as a preferable multicarrier modulation scheme. The modulated signals of a conventional orthogonal frequency division multiplexing system are complex and bipolar. In intensity-modulated direct detection optical wireless communications, transmitted signals should be real and unipolar due to non-coherent emissions of an optical light emitting diode. In this paper, different hybrid optical systems have been proposed to satisfy real and unipolar signals. Peak-to-average power ratio is one of the biggest challenges for orthogonal frequency division multiplexing-based visible light communications. They are based on a combination of non-linear companding techniques with spreading or precoding techniques. Simulation evaluation is performed under direct current-biased optical orthogonal frequency division multiplexing, asymmetrically clipped optical orthogonal frequency division multiplexing, and Flip-orthogonal frequency division multiplexing systems in terms of peak-to-average power ratio, bit error rate, and spectral efficiency. The proposed schemes are investigated to determine a scheme with a low peak-to-average power ratio and an acceptable bit error rate. MATLABTM software has been successfully used to show the validity of the proposed schemes.
Źródło:
Opto-Electronics Review; 2022, 30, 3; art. no. e141951
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of the Impact of Transient Disturbances on Railway Signaling Systems Using an Adapted Time-Frequency Analysis Method
Autorzy:
Kousri, M. R.
Deniau, V.
Heddebaut, M.
Baranowski, S.
Powiązania:
https://bibliotekanauki.pl/articles/226198.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
EMC
railways
signaling
transient disturbances
transient detection
cellular radio
bit error rate
Opis:
As many other industrial environments, the railway electromagnetic environment is characterized by a large number of electromagnetic signals and disturbances. Among these, transient signals, with high energy level and wide frequency spectrum, represent an important threat to different signaling subsystems. In this paper, a new methodology dedicated to the detection and the characterization of the transient disturbances is presented. Based on a flexible and adjustable time-frequency analysis, this methodology is used to evaluate the impact of transient disturbances on a ground-to-train radio communication. A test bench was developed in order to validate the results of this evaluation.
Źródło:
International Journal of Electronics and Telecommunications; 2017, 63, 4; 347-354
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design and performance evaluation of vehicular visible light communication system under different weather conditions and system parameters
Autorzy:
El-Mokadem, Eslam S.
Tawfik, Nagwan I.
Aly, Moustafa H.
El-Deeb, Walid S.
Powiązania:
https://bibliotekanauki.pl/articles/2204173.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
visible light communication
beam divergence
bit error rate
vehicular communication
laser diode
Opis:
Vehicular visible light communication is an emerging technology that allows wireless communication between vehicles or between vehicles and infrastructure. In this paper, a vehicular visible light communication system is designed using a non-return to zero on-off keying modulation scheme under the effect of different weather conditions such as clear, haze, and fog. The first model is a light emitting diode-based system and the second is a laser diode-based system. For both models, the influence of system parameters such as beam divergence, transceiver aperture diameters, and receiver responsivity is studied. The impact of the use of the trans-impedance amplifier is also investigated for both models. It was concluded that in the presence of the amplifier, output power of the light emitting diode and laser diode model are increased by 98.46 μW and 0.4719 W, respectively. The performance of the two proposed models is evaluated through bit error rate, quality factor, eye diagram, and output power to have some insightful results about the quality of service for the two proposed models. Under a specific weather condition, the performance of the system would be critical and other techniques should be applied. The maximum achievable link distance for the laser-based and light-emitting diode-based systems is 190 m at a data rate of 25 Gbps and 80 m at a data rate of 60 kbps, respectively, under the same system parameters and weather conditions. The obtained results provide a full idea about the availability of constructing our proposed model in a practical environment, showing a higher performance of the laser diode-based model than that of the light emitting diode-based model.
Źródło:
Opto-Electronics Review; 2023, 31, 2; art. no. e145580
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Different Transfer Functions for Optical Limiting Amplifier used in a 2R Burst Mode Optical Regenerator
Autorzy:
Deodhar, Yash
Reddy, Jeeru Jaya Sankar
Kakade, Priyanka Desai
Kakade, Rohan
Powiązania:
https://bibliotekanauki.pl/articles/1844502.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
optical limiting amplifier
burst mode
ASE noise
nonlinearity
bit error rate
optical regeneration
Opis:
The major difference between a continuous mode optical regenerator (CMOR) and a burst mode optical regenerator (BMOR) is that a BMOR is capable of handling large variations in the input power which makes it useful in optical packet switched and optical burst switched networks. This is due to the optical limiting amplifier (OLA) present in the BMOR. Using computer modelling, the impact of using different OLA non-linear transfer functions on the output bit error rate of a system consisting of a cascade of 2R BMORs has been investigated. The effect of amplified spontaneous emission (ASE) noise introduced in the inter-regenerator links has also been taken into consideration. Also, a brief review of existing OLA designs is presented.
Źródło:
International Journal of Electronics and Telecommunications; 2021, 67, 3; 409-416
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dimming control schemes combining IEEE 802.15.7 and SC-LPPM modulation schemes with an adaptive M-QAM OFDM for indoor LOS VLC systems
Autorzy:
Mohammed, Nazmi A.
Badawi, Kareem A.
Khalaf, Ashraf A. M.
El-Rabaie, S.
Powiązania:
https://bibliotekanauki.pl/articles/1818236.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
visible light communication
sub-carrier pulse position modulation
lightning topologies
bit error rate
Opis:
The presented work proposes a new dimming control schemes for indoor visible light communication which combines variable pulse-position modulation, colour shift keying as key schemes of IEEE 802.15.7 standard, and sub carrier-pulse-position modulation as a pulse-position modulation variant with orthogonal frequency division multiplexing. These schemes are then compared with traditional merging schemes utilizing pulse-width modulation and multiple pulse-position modulation with m-ary quadrature amplitude modulation OFDM. The proposed schemes are investigated in a typical room with a different lighting layout (i.e., distinctive and uniform lighting layout), followed by an illumination investigation to evaluate the performance of the proposed schemes, especially the enhanced achieved data rates, and to determine their limitations as reliable visible light communication systems that can satisfy both communication and illumination requirements.
Źródło:
Opto-Electronics Review; 2020, 28, 4; 203--212
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance Analysis of Filtered OFDM Based Downlink and Uplink NOMA System over Nakagami-m Fading Channel
Autorzy:
Mukhtar, Shaika
Begh, Gh. Rasool
Powiązania:
https://bibliotekanauki.pl/articles/1839342.pdf
Data publikacji:
2021
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
bit error rate
orthogonal multiple access
out-of-band emission
successive interference cancellation
Opis:
Efficient consumption of available resources and fulfillment of increasing demands are the two main challenges which are addressed by exploring advanced multiple access schemes along with efficient modulation techniques. To this end, non-orthogonal multiple access (NOMA) is discussed as a promising scheme for future 5G traffic. NOMA enables the users to share same resource block, permitting certain level of interference. In this paper, we propose filtered OFDM (F-OFDM) as a transmission waveform for NOMA systems, as it offers all the advantages of OFDM with the additional provision of sub-band filtering to satisfy the diverse services of the users. We examine F-OFDM in both downlink and uplink NOMA systems. Error-related performances of both downlink and uplink F-OFDM NOMA systems are analyzed and compared with conventional OFDM NOMA system over Nakagami-m fading channel. The results show that the error performance of F-OFDM NOMA is better than that of OFDM NOMA. An improvement of about 2 dB and 1 dB in bit error rate is achieved in downlink and uplink F-OFDM NOMA, respectively. Monte Carlo simulations are conducted for different values of fading parameter m, supporting the obtained analytical results.
Źródło:
Journal of Telecommunications and Information Technology; 2021, 2; 11-23
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cooperative communication with scheme selection
Autorzy:
Zadeh, S. V. M.
Fartash, B.
Powiązania:
https://bibliotekanauki.pl/articles/101926.pdf
Data publikacji:
2016
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
cooperative communication
channel information
symbol error rate
amplify and forward
decode and forward
Opis:
In this paper, a new cooperation scheme is provided that implements the advantages of both DF and AF schemes to enhance the performance in wireless networks. We suppose that nodes can access the channel information and based on this, the cooperation scheme is selected and applied. This algorithm is repeated when channel states have an effective variety. We apply this strategy to a single relay system with square MQAM signals where optimum power allocation is employed. Simulations and comparisons verify that symbol-error-rate (SER) performance can be improved properly.
Źródło:
Advances in Science and Technology. Research Journal; 2016, 10, 30; 19-23
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dimming control schemes combining IEEE 802.15.7 and SC-LPPM modulation schemes with an adaptive M-QAM OFDM for indoor LOS VLC systems
Autorzy:
Mohammed, Nazmi A.
Badawi, Kareem A.
Khalaf, Ashraf A. M.
El-Rabaie, El-Sayed
Powiązania:
https://bibliotekanauki.pl/articles/1818230.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
visible light communication
sub-carrier pulse position modulation
lightning topologies
bit error rate
Opis:
The presented work proposes a new dimming control schemes for indoor visible light communication which combines variable pulse-position modulation, colour shift keying as key schemes of IEEE 802.15.7 standard, and sub carrier-pulse-position modulation as a pulse-position modulation variant with orthogonal frequency division multiplexing. These schemes are then compared with traditional merging schemes utilizing pulse-width modulation and multiple pulse-position modulation with m-ary quadrature amplitude modulation OFDM. The proposed schemes are investigated in a typical room with a different lighting layout (i.e., distinctive and uniform lighting layout), followed by an illumination investigation to evaluate the performance of the proposed schemes, especially the enhanced achieved data rates, and to determine their limitations as reliable visible light communication systems that can satisfy both communication and illumination requirements.
Źródło:
Opto-Electronics Review; 2020, 28, 4; 203--212
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł

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