0000000000522737
AUTHOR
G. Andaloro
Anomalies in the temperature dependence of the 1.2-? absorption of liquid water
The weakly absorbed 1.2-μ combination band of water was accurately studied as a function of temperature, in both its profile and first derivative, to obtain information on the bulk properties of liquid water. Arrhenius plots of integrated component intensity ratios showed well aligned experimental points, except for a neatly defined break occurring in the 30 to 40°C temperature interval for pure water A similar break, shifted by some 18°C towards lower temperature, was found in the case of 1M NaClO4 aqueous solutions. The breaks are tentatively assumed to result from abrupt though subtle changes involving low-frequency modes. This tentative, assumption appears independent of specific models…
Construction and validation of a computer-based diagnostic module on average velocity
This article describes the process of building a computer-based diagnostic module concerning the understanding of the average velocity concept. The first step consists of the production of a student model that takes into account student errors and reasoning paths. The computer module formulates its diagnosis by leading users along different patterns foreseen according to the hypothesized student model. Results are reported concerning a correlation analysis between automatic and human diagnoses.
Student knowledge and learning skill modeling in the learning environment `forces'In order to prevent further delays in publication this paper has been published without the benefit of the authors corrections.
Abstract In this paper we present a student module modeling knowledge states and learning skills of students in the field of Newtonian dynamics. Student data recorded during the exploratory activity in microworlds are used to infer mental representations concerning the concept of force. A fuzzy algorithm able to follow the cognitive states the student goes through in solving a task and to interpret the monitored changes is discussed.
I.R. Experimental studies of dynamical aspects of water structure: Effects of HD substitution and of small solutes
Abstract Results on i.r. absorption spectra of H2O, D2O and electrolytic solutions and their thermal modifications are presented. From the data, some parameters can be obtained which are suitable for a description of dynamical aspects of water structure. Solute induced changes of these parameters provide a quantitative, although phenomenologic description of the water-solute interaction.
A computer-based diagnostic tutor for average velocity
Abstract The concept of average velocity is often misunderstood, even by students at university level. To analyse student reasoning about average velocity, students who were being instructed in kinematics in an introductory physics course were shown a series of computer animations of two cars moving independently. Their answers to subsequent questions tended to use partial knowledge elements present in the problem. On this basis, a list of eight procedures used by students was drawn up and used as the basis of a computer-based diagnostic tutor, Velo. The performance of Velo is being compared with human tutors.