1,721,011 research outputs found
Eyes on Kepler laws: a multimedia based on data/images by a planetarium
Full text link“Eyes on Kepler Laws” has been realised on the basis of data and dynamic images from the Planetarium in Caserta (Italy) (scientific director L.A. Smaldone, http://www.planetariodicaserta.it). The three Kepler’s laws are addressed in the case of the planets of the solar system.
The visualization of the planets’ motions, the surrounding stars and the Milky Way are based on real data and images. The polar projection (fish-eye format) allows to observe the full hemisphere of the sky. The time counters measure the time in Universal Time (U.T.).
Pedagogical Effectiveness and Transformation Potential.
These keywords summarise the educational contributions offered by “Eyes on Kepler Laws” in addressing some learning/teaching problems commonly encountered by students and teachers when the Kepler’s laws are studied (e.g. meaning of each law, similarities and differences in the planets’ orbits, evaluation of revolution periods, areal vs orbital velocity, etc.).
Two historical portraits show Tycho Brahe (1546 – 1601) and Johannes Kepler (1571 – 1630) together with the first edition of Quadrans Muralis (1598) and Astronomia nova (1609), Harmonices Mundi (1619). These allude to the great power of abstraction of the work by Kepler, based on the analysis of very many and much accurate observations by Tycho Brahe.
The connection between the orbits of the 8 planets in the solar system and their abstract representations as visualization of the orbits (dynamic display) can help the learners familiarise with these phenomena. The used planetarium images together with the possibilities of various viewpoints and scale changes (zooming in/out) produce a context very close to reality and much richer then that of a simulation based only on mathematical models. It is therefore possible to discuss power and limits of a model, approximations, graphic displays, etc...
The Kepler First Law and the difficulty in understanding the different eccentricity of elliptical orbits is addressed by visualising Mercury, Venus and Earth orbits, the last two being almost circular while the first is clearly elliptical.
The Second Law is clarified by analysing the motion of Mercury, with special focus on its position and velocity near perihelion and aphelion. The constancy of areal velocity can be checked be measuring the area swept off in four days of Mercury revolution (PM = 88 days).
The Third Law is addressed via the examples of Mercury and Venus; the periods and semi-axes of their dynamically shown orbits are measured and related.
The two planets move on the real background of a steady Milky Way and the moving Earth and Mars.
The well acknowledged Predict – Observe - Explain (POE) learning cycle can be easily implemented. The learners are initially asked to predict features of the motion of various solar planets; then the multimedia is used and the learners explain, with their words (orally or in writing) the results of their observations. The comparison between the P and O phases of the cycle allows to address possible learning difficulties. Iteration of the POE cycle facilitate both spiralling around Kepler’s Laws and addressing their content at diverse depth.
Eyes on Kepler Laws can be used for class activities, home work, tasks and problem-based learning. It is also appropriate in teacher’s education programs
L’insegnamento della fisica e delle scienze nella scuola; proposte operative per un approccio laboratoriale low-cost / no cost.
No full textAvviare i ragazzi allo studio di discipline scientifiche con forte componente sperimentale, come è la Fisica, significa essenzialmente contribuire alla formazione di una forma mentis scientifica adeguata alla corretta interazione con la realtà che li circonda. L’approccio sperimentale quantitativo è la base delle scienze, il provare e riprovare di Galileo, padre della metodologia alla base di tutte le scienze moderne, è tentare sensate esperienze. Le sensate (cioè concrete) esperienze consentono la lettura del gran libro della natura, che è scritto in caratteri matematici, come sostiene Galileo. L’interpretazione della natura si basa su modelli: la natura è il Gran Libro ed è dato; la questione è mettere i ragazzi in condizione di leggere tale libro.
Il primo passo all’indispensabile approccio laboratoriale è l’acquisizione del concetto di misura, diretta ed indiretta, come confronto tra una grandezza e la grandezza campione. Più semplice, più quotidiano è il campione utilizzato nelle prime esperienze di misura, più forte e duratura sarà la conoscenza maturata. Ecco un primo esempio di laboratorio a costo basso o nullo, ma di grandissima valenza: misure di lunghezze di banchi usando spaghi graduati (dagli stessi studenti), centimetri da sarto, righelli etc. e confronto dei risultati ottenuti.
Questo brevissimo corso offre un primo stimolo per sviluppare la fantasia e l’inventiva dei docenti nell’utilizzare materiali di riciclo e di uso quotidiano; esso si concentrerà, essenzialmente, su esperimenti di ottica: lenti di ingrandimento costruite con gocce d’acqua, lenti cilindriche realizzate riciclando vasetti di vetro o bottiglie riempite d’acqua, una camera oscura realizzata impiegando scatole di cartone, uno spettroscopio a visione diretta costruito con scatole di biscotti e vecchi CD, l’interferenza da fenditura realizzata usando puntatori laser reperibili sulle bancarelle e pellicola d’alluminio etc.
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Improving secondary students’ scientific literacy and laboratory skills: the Italian Project “Scientific Degrees”
No full textAn overview of the Italian National Project “Progetto Lauree Scientifiche” (PLS, Scientific Degrees Project
is presented (http://www.progettolaureescientifiche.eu/). The Project, established in 2005 by the
Ministry of Education, University and Research, was initially aimed at addressing the constant decrease,
since 2000, in the enrolment of secondary school students in tertiary scientific education. The involved
University degrees have been: Chemistry, Mathematics, Physics, Sciences of Materials. Due to the strong
focus on motivating students towards scientific-related professional careers, the Project was developed
in cooperation also with the Italian National Board of Industries, to give students an informed view about
employment possibilities in industrial companies. From the scientific viewpoint, the main objectives
have been to: enhance knowledge of Science contents and perception about Nature of Science through
laboratory activities that actively involve students; improve competences of in-service teachers on
laboratory activities focusing on both contents and methodological aspects; help students become
aware of their own scientific knowledge and of the pre-requisites requested to take full advantage of the
University curricula; deepen special Science topics for the most motivated students. In this paper, a brief
overview of the PLS Project is presented. Then, emblematic activities carried at the Naples Department
of Physics are described. Finally, some conclusions are drawn
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Learning and teaching motion: MBL approaches
No full textThe paper deals with some MBL approaches to teaching-learning motion in different school contexts. Positive global results indicate that open MBL approach can introduce significant innovative changes
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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