Optimal Nash tuning rules for robust PID controllers

In this paper, we propose tuning rules for one degree-of-freedom proportional-integral-derivative controllers, by considering important aspects such as the trade-off in the performance in the servo and regulation operation modes and the control system robustness by constraining the maximum sensitivity peak. The different conflicting objectives are dealt with by using a multi-objective optimization algorithm to generate the trade-off optimal solutions. In this context, a simple tuning rule is determined by using the Nash solutions as a multi-criteria decision making technique. The Nash criteria is shown to provide convenient trade-off solutions for the controller tuning problem. Illustrative simulation examples show the effectiveness of the method.     

Women,university and science in twentieth-century Spain

This article aims to question the widely accepted idea that female university students in Spain have, in the past, tended to opt for degrees in the field of humanities. Based on an analysis of the official statistics that are currently available, the paper demonstrates that Spanish female university students showed a clear preference for scientific studies, first medicine and later pharmacy. This pattern was not affected by Franco’s regime and remained stable until the great transformation of Spanish universities during the 1960s. Finally, the paper argues that the basic reasons for this preference for the scientific field were equal access to the prestigious male baccalaureate curriculum, which was a characteristic of the Spanish model for incorporating women into secondary education, and the uneven prestige of the professions to which the degrees provided access. The conclusion drawn is that, historically, pharmacy was the most common professional career pursued by female university graduates in Spain.     

Teams’ innovation: getting there through knowledge sharing and absorptive capacity

This study addresses the contribution of knowledge sharing behaviour and absorptive capacity to innovation at team level. Although the hypotheses reflect the dominant literature, the study’s novelty lies in the data collected from several industries in Portugal, avoiding possible industry bias. Relationships are tested outside sectors where traditionally team effects are studied, for example healthcare. Data were collected from 141 employees working in organizational teams, excluding top management teams, which are often the object of research addressing phenomena leading to innovation. There is no evidence in support of organizational size effect, team’s geographic concentration effect or gender effect. However, team tenure duration is positively related to increased knowledge sharing, that is, recent teams do not share as much knowledge as older ones. Structural Equation Modelling was used to test the mediation effect of absorptive capacity between individual knowledge sharing behaviour and team innovation. Evidence in support of full mediation was found.     

Los medios como soportes de sistemas de representación: Implicaciones educativas

En esta investigación didáctica se experimenta con el aprendizaje y uso de medios de creación y escritura audiovisual para establecer sus posibilidades educativas. El autor aboga por no encerrar los audiovisuales o los ordenadores en un «aula especial» sino integrarlos en el flujo educativo regular. La escritura audiovisual se presenta como una actividad marcadamente significativa para profesores y alumnos.     

Effects of academic dishonesty on dimensions of spiritual well-being and satisfaction: a comparative study of secondary school and university students

Recent research has shown an increase in academic dishonesty in different educational systems and levels, and negative effects on the academic institution, society and the students themselves. In order to describe the differential perception of academic dishonesty by Spanish secondary school and university students, and to study its consequences on psychological well-being, comparisons between two groups of students from secondary education and university were carried out, using measures of the perception and execution by others of dishonest behaviour, as well as psychological well-being and satisfaction with life and learning. University students revealed greater laxity of conscience, considering dishonest behaviour to be less serious and more common than secondary school students, and indulging in more dishonest behaviour themselves. They also showed greater spiritual, personal, community and environmental well-being, and greater satisfaction with learning. However, transcendental spiritual well-being was greater in the group of secondary education students. Academic dishonesty was associated with satisfaction with learning in both groups, and with satisfaction with life in secondary education. Its link with measures of spiritual well-being was greater in the group of secondary education students, being linked to transcendental well-being only in the group of university students. No gender differences were observed in any of the variables.     

Introduction to Semiconductor Physics in Secondary Education: Evaluation of a teaching sequence

The present article presents a didactic proposal oriented to teaching notions of semiconductor physics in secondary education. The methods and the results of a pilot study designed to analyse the effectiveness of a teaching sequence on the topic are also described. The subjects were 60 students, aged 14–15 years, of a secondary school in Seville, Spain. The levels of knowledge acquired by the students were evaluated by means of a test and personal interviews, which we also used to detect the most frequent obstacles they encountered against learning. Also, we employed personal interviews and analysis of the students’ notebooks to evaluate their attitudes towards semiconductor physics and its learning, and to evaluate the degree to which the teaching sequence fosters cooperative learning and the self‐regulation of learning. The results indicated that the students in general acquired ideas and reasoning in the appropriate line, although with some mistakes or inaccuracies with respect to scientific conceptions, and acquired positive attitudes towards the learning of semiconductor physics, with a high degree of motivation during the teaching–learning process. The conclusion is that it is possible to initiate teaching the basic notions of semiconductor physics in secondary education, although it is necessary to continue going deeper into the topic with new research. As a proposal for improvement in future actions, we formulate new objectives oriented at overcoming the students’ commonest obstacles against learning with respect to the topic.     

REEARCH REPORT

This paper addresses the concept of geological time as used by students who face tasks that demand three types of skills: to locate events in time, to order them according to time calendar, and to manage time intervals. The empirical study consisted of asking high school students as well as technical school students to carry out tasks that required the use of the three previously mentioned components. It was found, first, that students frequently used erroneous temporal labels, which shows a lack of knowledge that would allow them to locate events within the context of geobiologic data. Second, the students did not store the representation of a succession of events, but were nevertheless able to create it by means of the deductive use of previous knowledge. Finally, the importance of having an appropriate representation of geological time intervals became patent while observing the students' difficulties in understanding geologic changes.     

Cell-in-cell phenomenon in urinary sediment: a case report

The internalization of apoptotic cells by non-phagocytic cells has been observed in different tissues and could be an important mechanism for the elimination of dying cells. Here, we describe a probable event of phagocytosis of apoptotic cells mediated by urothelial cells in urinary sediment. A 90-years-old male patient was admitted unconscious to the hospital, visible signs included: pale skin and dry mucous membranes, presumptively diagnosed as dehydration. Blood test revealed anaemia (haemoglobin 130 g/L) and hyperglycaemia (glucose 7.8 mmol/L), urinalysis showed a picture of urinary tract infection (leukocyturia and bacteriuria). The microscopic analysis of urinary sediment revealed the presence of urothelial cells and leukocytes internalized in urothelial cells. Anti-CD68 (membrane marker of macrophages) was tested by immunocytochemistry and a negative result was observed. Based on the findings phagocytosis of apoptotic cells mediated by urothelial cells was identified. This phenomenon can be observed in urinary sediment and should not be confused with a neoplastic process since it is a physiological event of cell elimination.     

An Intellectual Capital perspective for Business Model Innovation in technology-intensive industries: empirical evidences from Italian spin-offs

Innovation and competition take place increasingly between Business Models (BM), and not just among products, processes, and technologies. Therefore, Business Model Innovation (BMI) becomes the key process to unleash value creation for both established and new companies, and, among these latter, particularly for technological spin-offs. For their constituent characteristics, it emerges that BMI in technological spin-offs appears to be related to the effective management of the Intellectual Capital (IC). Despite this, current research has paid little attention to decline BMI through the lenses of IC. This study aims to provide a contribution in this direction by investigating how technological spin-offs innovate their BM by leveraging their IC dimensions. A review of relevant literature on BMI has been carried out. Then, a case study methodology has been adopted to analyze seven technological spin-offs. The analysis highlighted three main trajectories of BMI, defined in terms of the BMI scope and the main exploited IC dimension. The discussion of findings from a research and practical perspective contributes to the debate on BMI, by providing a new interpretative key based on the relevance of the IC dimensions.