Bio-Inspired Filter Banks for SSVEP-based Brain-Computer Interfaces

Brain-computer interfaces (BCI) have the potential to play a vital role in future healthcare technologies by providing an alternative way of communication and control. More specifically, steady-state visual evoked potential (SSVEP) based BCIs have the advantage of higher accuracy and higher information transfer rate (ITR). In order to fully exploit the capabilities of such devices, it is necessary to understand the features of SSVEP and design the system considering its biological characteristics. This paper introduces bio-inspired filter banks (BIFB) for a novel SSVEP frequency detection method. It is known that SSVEP response to a flickering visual stimulus is frequency selective and gets weaker as the frequency of the stimuli increases. In the proposed approach, the gain and bandwidth of the filters are designed and tuned based on these characteristics while also incorporating harmonic SSVEP responses. This method not only improves the accuracy but also increases the available number of commands by allowing the use of stimuli frequencies elicit weak SSVEP responses. The BIFB method achieved reliable performance when tested on datasets available online and compared with two well-known SSVEP frequency detection methods, power spectral density analysis (PSDA) and canonical correlation analysis (CCA). The results show the potential of bio-inspired design which will be extended to include further SSVEP characteristic (e.g. time-domain waveform) for future SSVEP based BCIs.Comment: 2016 IEEE International Conference on Biomedical and Health Informatics (BHI

Export-led growth, real exchange rates and the fallacy of composition

exports, exchange rates

Dynamo action between two rotating discs

Dynamo action is considered in the region between two differentially rotating infinite discs. The boundaries may be insulating, perfectly conducting or ferromagnetic. In the absence of a magnetic field, various well-known self-similar flows arise, generalising that of von Kármán. Magnetic field instabilities with the same similarity structure are sought. The kinematic eigenvalue problem is found to have growing modes for Rem>Rc≃100. The growth rate is real for the perfectly conducting and ferromagnetic cases, but may be complex for insulating boundaries. As Rem→∞ it is shown that the dynamo can be fast or slow, depending on the flow structure. In the slow case, the growth rate is governed by a magnetic boundary layer on one of the discs. The growing field saturates in a solution to the nonlinear dynamo problem. The bifurcation is found to be subcritical and nonlinear dynamos are found for Rem≳0.7Rc. Finally, the flux of magnetic energy to large r is examined, to determine which solutions might generalise to dynamos between finite discs. It is found that the fast dynamos tend to have inward energy flux, and so are unlikely to be realised in practice. Slow dynamos with outward flux are found. It is suggested that the average rotation rate should be non-zero in practice

Auditor independence and earnings management

Abstract. This research paper investigates the auditor’s independence especially in today’s modern age where the role of auditor is becoming more and more important as businesses are developing and more and more use of technology, on one hand limits the use of personnel but on the other hand hides the possible effects of human error makes the job even more difficult. So, this paper investigates that how independent the auditors are in today’s world and what are the factors that can affect their independence like non-audit services and what sort of affects, auditor independence can have on earnings management and some suggestions that how the auditors can actually be independent instead of hiding behind the image of being independent when actually they are just a dummy in the hands of the management. I have examined the independence of the auditor by the provision of non-audit services and to what extent auditors independence can allow management to do earnings management or window dressing in Finnish markets by taking the data of the Finnish listed companies. I have used three hypotheses to prove that either the provision of non-audit services does affect the independence or not and to what extent earnings management can be linked with loss of auditor independence. I have used yearly regression model initially and tested the same models with pooled regression models. The yearly tests which I have used suggest that there is a positive relationship between audit and non-audit fees. Though I couldn’t find significant results for either of relationship between audit fees and discretionary accruals or non-audit fees and discretionary accruals, a measure of earnings management. When I used pooled regression model, I do find positive relationship between audit and non-audit fees. I also found positive relationship between audit fees and discretionary accruals, when the results were insignificant in yearly regression model. The pooled regression results for relation between non-audit fees and discretionary accruals were insignificant though. So, my findings were not enough to prove that auditors do lose their independence because of provision of non-audit services and that to what extent auditors independence can give room to management for earnings management

Investigation of the coupling asymmetries at double-slit interference experiments

Double-slit experiments inferring the phase and the amplitude of the transmission coefficient performed at quantum dots (QD), in the Coulomb blockade regime, present anomalies at the phase changes depending on the number of electrons confined. This phase change cannot be explained if one neglects the electron-electron interactions. Here, we present our numerical results, which simulate the real sample geometry by solving the Poisson equation in 3D. The screened potential profile is used to obtain energy eigenstates and eigenvalues of the QD. We find that, certain energy levels are coupled to the leads stronger compared to others. Our results give strong support to the phenomenological models in the literature describing the charging of a QD and the abrupt phase changes.Comment: conference paper, 50th anniversary of Aharonov-Bohm effec

Pretratamiento enzimático en el prensado en frío: Influencia en los aceites de linaza, hueso de albaricoque y semilla de uva

A commercial enzyme preparation consisting of pectolytic, cellulotic and hemicellulotic enzymes was applied to the oil extraction by cold pressing from apricot kernel, flaxseed and grape seed. The effects of enzyme pre-treatment varied depending on the different oil seed used as raw material. Although the increase in free fatty acidity can be considered as a negative effect (from 0.37 to 0.52), the decrease in peroxide number and p-anisidine values, increase in oil yield (22.75%), higher levels of total carotenoids and tocopherols, as well as a remarkable increase in phenolic content (x1.68) and radical scavenging effect (including hydrophilic and lipophilic-induced and total antioxidant capacity) showed that the use of enzyme application in the cold pressing of apricot kernel oil would be beneficial. Many of these positive results could not be achieved in the pressing of flaxseed or grape seed oils under the same conditions. A high negative correlation (r=-92.2) was found between p-anisidine value and δ-tocopherol for grapeseed oil. Hydrophilic and lipophilic antioxidant capacity, total phenolics, and total carotenoids negatively correlated well (r values above 80) with peroxide values for apricot seed oil. Correlation results showed that carotenoids play an important role in the oxidative stability of the oils, where it was much more evident for apricot seed oil (r=-97.5).Se aplicó un preparado enzimático comercial que consta de enzimas pectolíticas, celulóticas y hemicelulóticas en la extracción de aceite de prensado en frío de albaricoque, linaza y semilla de uva. Los efectos del pretratamiento enzimático variaron dependiendo de las diferentes semillas oleaginosas como materia prima. Aunque el aumento de la acidez libre puede considerarse como un efecto negativo (de 0,37 a 0,52), la disminución del valor de peróxidos y de p-anisidina, el aumento del rendimiento de aceite (22,75%), niveles más altos de carotenoides totales y tocoferoles, además de un aumento notable en el contenido de fenoles (x1.68) y el efecto captador de radicales (incluida la capacidad antioxidante total e inducida por hidrófilos y lipófilos) mostraron que la aplicación de enzimas en el prensado en frío del aceite de hueso de albaricoque resulta beneficioso. Muchos de estos resultados positivos no se pudieron lograr al prensar los aceites de semillas de linaza y uva, en las mismas condiciones. Se encontró una alta correlación negativa (r = -92.2) entre el valor de p-anisidina y el δ-tocoferol para el aceite de semilla de uva. La capacidad antioxidante hidrófila y lipófila, los fenoles totales y carotenoides totales se correlacionaron negativamente bien (valores de r por encima de 80) con los valores de peróxido para el aceite de semilla de albaricoque. Los resultados de correlación mostraron que los carotenoides juegan un papel importante en la estabilidad oxidativa de los aceites, mucho más evidente para el aceite de hueso de albaricoque (r = -97,5)

Approximate Computation of DFT without Performing Any Multiplications: Applications to Radar Signal Processing

In many practical problems it is not necessary to compute the DFT in a perfect manner including some radar problems. In this article a new multiplication free algorithm for approximate computation of the DFT is introduced. All multiplications $(a\times b)$ in DFT are replaced by an operator which computes $sign(a\times b)(|a|+|b|)$. The new transform is especially useful when the signal processing algorithm requires correlations. Ambiguity function in radar signal processing requires high number of multiplications to compute the correlations. This new additive operator is used to decrease the number of multiplications. Simulation examples involving passive radars are presented