Monitoring Dynamic Recrystallisation in Bioresorbable Alloy Mg-1Zn-0.2Ca by Means of an In Situ Acoustic Emission Technique

The tensile behaviour of the biocompatible alloy Mg-1Zn-0.2Ca (in wt.%) in the fine-grained state, obtained by severe plastic deformation via multiaxial isothermal forging, has been investigated in a wide range of temperatures (20 ÷ 300) °C and strain rates (5 × 10−4 ÷ 2 × 10−2) s−1 with the measurements of acoustic emission (AE). The dependences of mechanical properties, including the yield stress, ultimate strength, ductility, and the strain-hardening rate, on the test temperature and strain rate, were obtained and discussed. It is shown for the first time that an acoustic emission method is an effective tool for in situ monitoring of the dynamic recrystallisation (DRX) process. The specific behaviour of the acoustic emission spectral density reflected by its median frequency as a function of strain at various temperatures can serve as an indicator of the DRX process’s completeness.

Behawioralne finanse przedsiębiorstw jako interdyscyplinarny nurt neoklasycznej teorii finansów

Nowadays, we see increasing interconnections between different scientific disciplines. It is becoming increasingly difficult for scholars to practice exclusively within their own field. Economics, finance and related disciplines, in recent years, have made extensive use of theoretical and empirical findings of other social sciences. The aim of this article is to present the issue of behavioural finance, the assumptions of which make it easier to understand what and why makes financial managers choose a particular course of action. Focusing on the tendencies of a psychological nature characteristic of managers that determine their specific behaviour, it is explained how the behaviour of finance professionals can be analysed through the prism of psychology. The article is based on the analysis of the literature on the subject, where the method of source analysis was mainly used.

Lecture 10: Rhetoric and Behavioral Economics

Although behavioural economists are not rhetoricians, and rhetoricians are not behavioural economists, they are both interested in persuasion, even as they come at it from different points of view. Lecture 10 argues that behavioural economics examines our choice-making practices and considers how a range of influences works in concert with conventional economic interests to shape the procedures by which we come to decisions. These influences use rhetoric to nudge people to adopt particular beliefs, engage in specific behaviour, and endorse ideas believed to be in the public interest. Les économistes comportementaux ne sont pas rhétoriciens, et les rhétoriciens ne sont pas économistes comportementaux, mais ils s’intéressent tous les deux à la persuasion, même si leurs points de vue diffèrent. Le cours 10 soutient que l’économie comportementale examine notre manière de faire des choix et il considère comment un éventail d’influences, de concert avec des intérêts économiques conventionnels, façonne les procédures par lesquelles on prend des décisions. Ces influences utilisent la rhétorique afin d’inciter les gens à adopter des croyances particulières, adopter des comportements spécifiques, et appuyer des idées censées être dans l’intérêt public.

Design of a Characterisation Environment for a MEMS Ultrasound Sensor under Guided Ultrasonic Wave Excitation

Microelectromechanical Systems (MEMS) are a current subject of research in the field of structural health monitoring (SHM) for the detection of guided ultrasonic waves (GUW). The dispersive behaviour of GUW, reflections and other kinds of wave interactions might result in a complex wave field that requires a specific analysis and interpretation of the recorded signals. This makes it difficult or impossible to interpret the sensor signal regarding the distinguishability between the sensor transfer behaviour and the specific behaviour of the test structure. Therefore, a proper application-suited design of the tested structure is crucial for reliable sensor characterisation. The aim of this contribution is the design and evaluation of a setup that allows a representative situation for a GUW application and provides a defined vibration energy for a MEMS sensor characterisation. Parameters such as the specimen’s geometry, material properties and the sensor specifications are taken into account as well as the experimental settings of the GUW excitation. Furthermore, the requirements for the test application case are discussed.

Self-care tooling innovation in a disabled kea (Nestor notabilis)

Tooling is associated with complex cognitive abilities, occurring most regularly in large-brained mammals and birds. Among birds, self-care tooling is seemingly rare in the wild, despite several anecdotal reports of this behaviour in captive parrots. Here, we show that Bruce, a disabled parrot lacking his top mandible, deliberately uses pebbles to preen himself. Evidence for this behaviour comes from five lines of evidence: (i) in over 90% of instances where Bruce picked up a pebble, he then used it to preen; (ii) in 95% of instances where Bruce dropped a pebble, he retrieved this pebble, or replaced it, in order to resume preening; (iii) Bruce selected pebbles of a specific size for preening rather than randomly sampling available pebbles in his environment; (iv) no other kea in his environment used pebbles for preening; and (v) when other individuals did interact with stones, they used stones of different sizes to those Bruce preened with. Our study provides novel and empirical evidence for deliberate self-care tooling in a bird species where tooling is not a species-specific behaviour. It also supports claims that tooling can be innovated based on ecological necessity by species with sufficiently domain-general cognition.

Missing value or behaviour: how to increase the signal of social media data

Social media has become a widespread element of people’s everyday life, which is used to communicate and generate contents. Among the several ways to express a reaction to social media contents, the “Likes” are critical. Indeed, they convey preferences, which drive existing markets or allow the creation of new ones. Nevertheless, the appreciation indicators have some complex features, as for example the interpretation of the absence of “Likes”. In this case, the lack of approval may be considered as a specific behaviour. The present study aimed to define whether the absence of Likes may indicate the presence of a specific behaviour through the contextualization of the treatment of missing data applied to real cases. We provided a practical strategy for extracting more knowledge from social media data, whose synthesis raises several measurement problems. We proposed an approach based on the disambiguation of missing data in two modalities: “Dislike” and “Nothing”. Finally, a data pre-processing technique was suggested to increase the signal of social media data.

Mathematical modeling of bioprocesses with the use of fractional order derivatives

This work brings together two recently discussed topics: mathematical modeling of a bioreactor and working with derivatives of non-integer order. Generally, it turns out that it is reasonable to replace the integer order derivatives in some of the already well known mathematical models describing bioprocesses with fractional order ones. However, the specific structure of such type of derivatives makes the study of the properties of the models a real challenge. This work contains primary results for modeling of a bioreactor with appropriately selected numerical approximations. Different scenarios are taken into consideration: starting from the simplest one - without mortality and then complicating by adding nonzero mortality term. In the classical case the solution of the system of differential equations describing the process has a specific behaviour in terms of monotonicity. Therefore, the focus of the further examinations is to find out whether it is possible to generalize the model into a fractional order one such that the key properties considering monotonicity still hold. The results show that the latter requires certain dependencies between the orders of the derivatives in the mathematical model. The hypothesis is based on two types of experiments which are described in detail. Lotka-Volterra and Monod specific growth rate are used in the mathematical model. The paper contains figures which illustrate the results from different numerical computations performed via Wolfram Mathematica software.

Personality of hosts and their brood parasites

Brood parasites such as the common cuckoo Cuculus canorus exploit the parental abilities of their hosts, Hosts avoid brood parasitism and predation by showing specific behaviour such as loss of feathers, emission of fear screams and contact calls, displaying wriggle behavior to avoid hosts or potential prey, pecking at hosts and prey and expressing tonic immobility (showing behaviour like feigning death or rapid escape from predators and brood parasites). These aspects of escape behavior are consistent for individuals but also among sites, seasons and years. Escape behaviour expressed in response to a broad range of cuckoo hosts and prey are consistently used against capture by humans, but also hosts and brood parasites and predators and their prey. An interspecific comparative phylogenetic analysis of escape behavior by hosts and their brood parasites and prey and their predators revealed evidence of consistent behaviour when encountering potential parasites or predators. We hypothesize that personality axes such as those ranging from fearfulness to being bold, and from neophobic to curiosity response in brood parasites constitute important components of defense against brood parasitism that reduces the overall risk of parasitism.