The bispectrum has a different analysis functions compared to the power spectrum analysis. The bispectrum provides additional information for nonlinear or non-Gaussian data, and also the method gives detailed information on the phase information signal. In this study, bispectrum and energy analysis was performed for wind speed data for the regions of Turkey Kırklareli. Hourly wind speed data of Kırklareli Region belonging to the year 2011 is used. Data were obtained from The General Director of Meteorology, Ankara, Turkey. As well as time-amplitude graph, energy graph obtained and monthly analysis is made of this diagram. Subsequently, sufficiency level of speed zones has been tested frequency from time and frequency information by obtaining spectrograms of velocity information. Random processes which are described more accurately than statistically and high grade statistics for processing phase information (more than two) and studies on spectrum can provide useful results. In this context, bispectrum of annual velocity information was obtained. In addition to the bispectrum analysis, methodology of the diagonal slices spectrum is used for data which do not show mark in the non-linear structure or Gaussian distribution researches. Also, after obtaining bispectrum surfaces, monthly results through these charts were found and evaluated by removing diagonal slices analysis. Peaks in the bispectrum indicates the frequency component and phase overlap in the signal. By means of these analyses, the frequency component and phase conflict are determined in the wind speed data. The results of the analysis determined by the energy level was consistent with the wind speed. Wind speed phase-coupling and diagonal slices are calculated. As a result of the calculations, it is determined low and high frequency groups. 

No abstract

Ferroresonance is a nonlinear phenomenon that damages the undesired, destructive system for energy transmission lines. The formation and development of this overvoltage ferroresonance phenomenon is an important research topic as a mysterious event in energy power systems. In this study, Seyit Omer-Iklar energy transmission line from Turkey’s electrical transmission networks was modelled using real parameters. Ferroresonance scenario was created on the model. The energy transmission system with the scenario is set to a simulation time of 4 seconds. The first two seconds are set to normal. By cutting off the transmission line in the 2nd sec., the system is provided with ferroresonance drift. According to the data obtained therefrom, spectrograms, instantaneous amplitude, instantaneous frequency and instantaneous phase were conducted. The analyses have made clear that the instantaneous frequency amplitude defined the system’s ferroresonance moment very well.

Bu çalışmada Elektroensefalogram (EEG) sinyallerinin analizi ve bu analiz üzerinden sınıflandırılması amaçlanmıştır. Bu amaçla EEG işaretleri Hilbert Huang metodu ile alt frekans bantlarındaki bileşenlerine ayrılmış, anlık frekans ve marjinal izge vektörleri elde edilmiştir. Bu vektörler ve bileşenler kullanılarak istatistiksel öznitelikleri çıkarılmıştır. Bu öznitelikler göz açık – göz kapalı , sağlıklı-epileptik ve epileptik nöbet alt sınıflarında incelenmiş, destek vektör makinesi (DVM), yapay sinir ağları (YSA) ve doğrusal ayrım analizi (DAA) algoritmaları ile sınıflandırılmış ve sonuçlar karşılaştırmalı olarak tartışılmıştır.

In this study, Bicoherence method was applied to analyze the state of 6 ceramic plates made from the same material is cracked or not. Of all six plates, while 1 consisted of an undamaged plate, the other 5 comprised of cracked plates. Cracks in damages plates have non-identical deformations. The centre points of the plates were applied to shock at equal severity by means of the pendulum. The sound, which emerged as a result of the impact, was recorded and transferred to the data processing environment. A single bicoherence peak was observed at the centre of the durable plate and more than one peak was seen in the cracked plates by the analysis conducted, in addition, their magnitudes were so much smaller than those of durable plates. While large rising magnitudes were formed at the centre on the bi-coherence plane of the durable ceramic plate, more than one bicoherence peaks, with low magnitudes, were formed on the cracked ceramic plates. Differentiation and feature extraction can clearly be identified in the feature diagonal slice analysis of the cracked plates with the bicoherence analysis carried out. While maximum bicoherence coordinates were formed in the coordinate centre of the durable ceramic plate, deviation from the centre presented itself in the cracked ceramic plates.