Cognitive agents — a procedural perspective relying on the predictability of Object-Action-Complexes (OACs)

Embodied cognition suggests that complex cognitive traits can only arise when agents have a body situated in the world. The aspects of embodiment and situatedness are being discussed here from the perspective of linear systems theory. This perspective treats bodies as dynamic, temporally variable entities, which can be extended (or curtailed) at their boundaries. We show how acting agents can, for example, actively extend their body for some time by incorporating predictably behaving parts of the world and how this affects the transfer functions. We suggest that primates have mastered this to a large degree increasingly splitting their world into predictable and unpredictable entities. We argue that temporary body extension may have been instrumental in paving the way for the development of higher cognitive complexity as it is reliably widening the cause-effect horizon about the actions of the agent. A first robot experiment is sketched to support these ideas.We continue discussing the concept of Object-Action Complexes (OACs) introduced by the European PACO-PLUS consortium to emphasize the notion that, for a cognitive agent, objects and actions are inseparably intertwined. In another robot experiment we devise a semi-supervised procedure using the OAC-concept to demonstrate how an agent can acquire knowledge about its world. Here the notion of predicting changes fundamentally underlies the implemented procedure and we try to show how this concept can be used to improve the robot’s inner model and behaviour. Hence, in this article we have tried to show how predictability can be used to augment the agent’s body and to acquire knowledge about the external world, possibly leading to more advanced cognitive traits.     

On a generalised plane strain crack problem for inhomogeneous anisotropic elastic materials

A generalised plane strain crack problem is considered for a class of inhomogeneous anisotropic elastic materials. The problem is reduced to a boundary integral equation involving hypersingular integrals. The boundary integral equation may be solved numerically using standard procedures. Some crack problems for a particular inhomogeneous material are considered in detail and the stress intensity factors are obtained in order to assess the effect of the anisotropy and inhomogeneity on the stress field near the crack tips.     

A service interruption free testing methodology for IEDs in IEC 61850-based substation automation systems

This paper presents a methodology for the testing of intelligent electronic devices (IEDs) in IEC 61850-based substation automation systems (SAS), without any service interruption to the end users, during the testing process. IEC 61850-based SAS provides opportunities for a new level of substation operation, enhancing operating efficiency, and protection reliability based on Ethernet-based communication networks. Due to these changes to the conventional substations, importance and dependency on IEDs is increasing rapidly. Frequency of faults occurring in the power systems is random in nature and is unpredictable. It is necessary to test and maintain the IEDs to ensure their proper operation at crucial times. This paper presents a novel methodology for testing the IEDs, without compromising the service reliability during the testing process. The proposed methodology exploits the inherit characteristics of IEC 61850 standard i.e. Network - based communication, interchangeability between multivendor IEDs, and engineering based on substation configuration language (SCL) files. The feasibility and robustness of the proposed method has been verified by performing several performance verification tests with different performance metrics.     

Comparison of the performance of the class modelling techniques UNEQ,SIMCA, and PRIMA

Derde, M.P. and Massart, D.L., 1988. Comparison of the performance of the class modelling techniques UNEQ, SIMCA, and PRIMA. Chemometrics and Intelligent Laboratory Systems, 4: 65-93By means of a Monte Carlo study a systematic comparison of the supervised pattern recognition techniques of the class modelling type, UNEQ, SIMCA and PRIMA is made. In particular, the success rate of the classification decisions and the influence of the sample size on it were investigated.It was concluded that better class models are obtained when a technique is used that takes the shape of the population distribution into account. If the actual distribution cannot be determined, then use should be made of techniques that make no or only weak assumptions about the shape of the distribution. However, even then it remains worthwhile to investigate whether the variables are correlated and to take this information into account.When using SIMCA and PRIMA, attention should also be paid to the way the class models are defined: an approach that makes use of certain sample parameters such as the range of the variables or the maximum distance between a training object and the class model might lead to overly broad models, especially for large training sets.     

Preparation of low- and medium-molecular weight chitosan nanoparticles and their antimicrobial evaluation against a panel of microorganisms,including cheese-derived cultures

This study employed the technique of ionic gelation in the manufacture of low- and medium-molecular weight chitosan nanoparticles. Nanoparticles were characterised (size, size distribution, surface charge and morphology) and their antimicrobial activity assessed against cheese-derived cultures, as well as a select panel of Gram-positive and Gram-negative microorganisms. Antimicrobial activity was determined by the minimum inhibition concentration via the micro dilution method using 96-well microplates. Synthesised particles were small-sized, with a moderate size distribution and positive zeta potential. Generated nanoparticles exhibited successful solubility in both water and acetic acid. Acidic nanosuspensions demonstrated greater microbial reduction than water-based nanoparticles, with no difference in activity observed between molecular weights. Cheese-derived cultures were effectively controlled, and Gram-negative species were more susceptible than Gram-positive species to the action of nanoparticles in acetic acid. Nanoparticles suspended in an acidic-based medium show promise as antimicrobial agents, particularly for use with cheese products.     

A cellular automaton simulation tool for modelling seismicity in the region of Xanthi

Seismicity is an extended geophysical characteristic of the Greek dominion. There are certain areas of high seismic activity, as well as, regions of low seismicity where strong earthquakes are rather rare events. Consequently, it is of great interest to present a methodology concerning the earthquake process in Greece even for areas considered to be of low seismicity. In this paper, a study of the earthquake activity of an area in Northeastern Greece, centred at Xanthi, Thrace, extending over a region of radius R = 80 km, during a certain time period is presented. A two-dimensional cellular automaton (CA) dynamic system consisting of cells representing charges is used for the simulation of the earthquake process. The model has been tested as well as calibrated using the recorded events of the above-mentioned region as initial conditions. The simulation results are found in good quantitative and qualitative agreement with the Gutenberg–Richter (GR) scaling relations. Finally, the CA model has a user-friendly interface and enables the user to change several of its parameters, in order to study various hypotheses concerning the seismicity of the region under consideration.     

Structure elucidation and toxicity analyses of the degradation products of aflatoxin B1 by aqueous ozone

Earlier researches showed that aflatoxin B₁ (AFB₁) can be effectively degraded using ozonation in the aqueous systems. However, the degradation products have not been identified until today. In this article, the degradation products of AFB₁ were analyzed using ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometers (UPLC Q-TOF MS). Under our experimental conditions, six key degradation product structures and possible paths for generating fragment ions were proposed. The proposals were based on the low mass error, high match rate in degradation product speculation, and possible molecular formulas that could be obtained using UPLC Q-TOF MS. UPLC revealed the existence of degradation products, whereas Q-TOF MS exposed the structures of the fragment ions for AFB₁ and its degradation products. Due to the conjugate addition reaction on the double bond of the terminal furan ring for AFB₁, the toxicity of the degradation products was significantly decreased compared with that of AFB₁ through the toxicity analysis of the degradation products according to the structure–activity relationship. The results showed that aqueous ozone treatment was an effective method for degrading AFB₁.