Didactic Books Research Articles

Contextualized education with the semiarid: analysis of teaching books of fundamental teaching II used in the Piamonte region of Diamantin-BA

The discourse of coexistence with the semi-arid region seeks to demystify the image of a semi-arid region represented by drought, dead animals and water scarcity. Relying on the discussions of socioeconomic, cultural, socio-environmental, economic, political and educational phenomena. Thus, the textbook must be understood within the context of social dialogue, contributing to the work of the teacher (a). The objective of this work is to analyze the didactic books of Portuguese, Mathematics, History, Geography and Sciences of Elementary School II of the schools of the public network of Piedmont da Diamantina in Bahia, as well as the presence of contextualization on the Semiarid. We analyzed the books cited according to criteria and descriptors related to living with the Semiarid. All the books were considered decontextualized, although some, mainly those of geography and those of science, approached some aspects related to Semiarid. The textbooks of elementary school II used in the public network in the Piedmont region of Diamantina / BA, do not present contextualization with the Semiarid.

Don't memorize theorem proofs! The Modern Geometry of Osvaldo Sangiorgi

This paper aims to examine how deductive geometry was constituted in two didactic book collections by Osvaldo Sangiorgi — named by pre-modern (1950s) and the modern (1960s) ones. The guiding question of the study is: how does Sangiorgi change the proposal of a deductive geometry for the 3rd grade of junior Brazilian high schools in the modern collection compared to the pre-modern collection? Postulates, theorems, and demonstrations are examined in detail, emphasizing the quantitative and qualitative aspects, as well as the methodological recommendations. This analyzes shows that the modern collection brought about significant changes and contributions both in the scope of Euclidean geometry, of a geometry to teach, and in the methodological didactic aspects by proposing the insertion of exploratory and experimental exercises, different registers of representations, which means, in our point of view, a geometry for teaching, which can be interpreted as an intuitive geometry, taken from the 1st and 2nd grades of the Brazilian Minimum Program of 1951.

The Boundless Friendship between Velpari and Kapilar in Classical Literature

This article sets out to know the opinions of poets, scholars, and sages in classical literature such as Ettuththokai (Eight Anthologies), Pathuppattu (The Ten Idylls), Pathinenkilkanakku (18 books), Didactic books, and Moral literature. And also, to explore the power of unadulterated honesty, truth, and dignity in friendship. Moreover, Kapilar was a great poet who was the chief scholar of the Tamil Sangam in education, questions, and in Madurai, the city where Tamil was developed with the various periods of Sangam as First Sangam, Middle (Idai) Sangam, and Last (Kadai) Sangam. Most of the songs in Sangam literature are sung by Kapilar.It has been thoroughly researched about the excellence of the friendship between the poet Kapilar and Velpari, the leader of the Velirkulam who ruled the small land of Parambu Nadu within the boundaries of the Pandya Empire, the grammar of friendship, the necessity of friendship, and friendship, as well as the unethical friendship that has been dealt with in Purananuru, Patirupattu, Siruppanaartuppai, Thirukkural, and Naladiyar. In the classical literature, the way in which Velpari and Kapilar valued friendship more than life, and the high spirit of Kapilar who stood as a close supporter of Velpari and guided Pari to defeat the enemy and helped him to achieve victory in the time of great suffering, is also explored in this article. Knowing that Pari cannot be defeated in a face-to-face fight, Moovendars (Three Great Kings) kills Pari by stratagem. After Velpari's death, Kabila, who had intended to sacrifice himself, changed his mind, thinking that if he too died, both of Pari's daughters would be left in a state of destitution. Kapila intended to get Pari's daughters married and appealed to the chieftains, Ilavachiko and Irungo, to share the fame of Pari and marry his daughters. Fearing the enmity of the Moovendars, the two small land leaders refused to accept Kapilar's request. Kapilar, who was heartbroken and without Pari, wanted to die. Kapilar handed over Pari's daughters to a brahmin who was close to him and gave up his life from the north.

Creation and formation of information resources for children

It should be noted that according to information obtained from written sources, the first book for children appeared in India in the 6th century BC. This didactic book tells about the moral and political conversations of a Brahmin in order to educate the ruler's son. The book, written in an entertaining style, consists of stories and fairy tales. In some sources, it is possible to find information that Confucius transcribed Chinese classics for children during that period. However, it is noted that this work has not been completed and the work remains unfinished. In the 600s AD, during the Anglo-Saxon period, monks and other scholars wrote a "textbook" for children. Aldhelm, Abbot of Malmesbury and Bishop of Sherborne, went down in history as the first person to write a textbook for children. His book De Septenario, de Metris, Enigmatibus ac Pedum Regulis contains a long essay on the meaning and use of the number seven in the Bible. Aldhelm assigned 1500 writing samples for children. He used question-and-answer form or wrote in poem form in all his manuals. Bede (673-735) used more imagination than Aldhelm. One of his most famous works was called "De Natura Rerum". Containing information on the natural sciences, history, astronomy and botany, this work has been used as an English textbook for more than three hundred years. Much of the content of Bede's works is a repetition of the scientific treatises of Plato, Aristotle, St. Augustine, and others [4, p.1].

Analysing the musical elements of the Book of Inci for Piano Teaching


 The aim of the study is to contribute to the repertoire of piano teaching by conducting a musical analysis of the piano album ‘Inci'nin Kitabı’. The research is an example of a case study, one of the qualitative research techniques. Each piece in the research has been evaluated individually according to the elements determined in line with the descriptive analysis. Each piece has been examined primarily in terms of musical elements. Later, the musical expressions, tempo terms and rhythmic elements of the pieces are measured and evaluated. The sources examined in the study and the data obtained from the pieces in Inci’s Book have been interpreted with the descriptive analysis method. It has been concluded that Inci’s Book, which has been defined as an enjoyable and didactic book in the piano teaching, is an appropriate and beneficial resource for piano students’ learning at different levels.
 
 Keywords: Ahmed Adnan Saygun; Inci's Book; music education; piano students’ learning; piano teaching.

Self- Access Materials Needed for Autonomous Learning in the 21st Century at Senior High School

The existence of the covid- 19 pandemic can indeed be a polemic in all sectors, particularly in education sector. Besides the covid- 19 pandemic, the rapid progress of the 21st encourages students to become independent learners who can pursue their own studying. Self- access materials play a crucial role in the successful execution of autonomous learning goals in promoting the ability and passion of students for autonomous learning. Therefore, this research aims to find out self- access materials needed for autonomous learning in the 21st century and investigate how to implement the self- access materials for autonomous learning in the 21st century. This research is a descriptive qualitative research using interview to collect the data. The respondents of this research are 6 students of XI Grade and 1 English teacher. The result shows there are 6 strategies of autonomous learning which consist of 17 autonomous learning activities. From the 17 autonomous learning activities, there are 13 autonomous learning strategies that found in this research with 1 activities founded regarding to the interviewees responses. The self- access materials needed by students are didactic books, motivational videos, dictionary applications, YouTube, vocabulary books, registers, authentic materials, English textbooks according to curriculum, webtoons, novels, feedback worksheet, TOEFL CD-Room, educational software (British Council, BBC Learning English and social media, articles, Ome TV application and others. There are 7 steps to implement the self- access materials. Thus, to support the English learning, this research greatly beneficial for students, teachers and material developers

The “evidential paradigm” in Persian Classics: princes from Sarandip and other clue interpreters

The rich history of Persian literature reception in the West includes such a major event as the translation of the Persian narrative into European languages. This has influenced the comprehension of a new epistemological paradigm in the humanities. The story under discussion is the first chapter of Amir Khusrav Dihlavi’s poem “Eight Paradises” (Hašt bihišt, 1299–1301), in which the Indian princess tells the Sassanian king Bahram Gur a tale of three princes from Sarandip (Sri Lanka, Ceylon). As the plot progresses, the princes restore the events of the past according to clues and signs and repeatedly demonstrate their firāsa or ability to guess based on the analysis of evidence. The stages of European reception of this story are well known. All this material is discussed in the methodologically famous work “Clues: Roots of an Evidential Paradigm” (1986) by Carlo Ginzburg, who connected the “evidential paradigm” with the Arabic firāsa, a “complex notion which, in general, designated the ability to pass, on the basis of clues, directly from the known to the unknown”; Ginzburg noted that the Sarandip princes were famous exactly for that ability. In this article, the Persian prose sources of the Three princes tale are under discussion, as well as some other sagacity stories from Persian didactic books (adab). Among the detective characters Abū ʻAlī ibn Sīnā gained particular popularity; in some stories, the great philosopher and author of the fundamental canon “The Medicine” acts as a doctor who recognizes a disease by symptoms and at the same time as a detective who restores the course of events from evidence and refutes unfair accusations before a judge.

Vocative and nominative as an appellation: the language norm formation in the Soviet period

Background. The authors of Ukrainian grammar books published before 1933 were consentient that appellation expressed by a noun requires the use of the vocative case only. In 1933, new People’s Commissar of Education of the USSR V. Zatonskyi formed the commission ‘for auditing the work on the language front’. On the 26th of April, the Commission adopted several resolutions, among which there was the provision to review scholar and didactic books to reveal ‘nationalistic deformation’. After they had been made public, in the Soviet handbooks for higher and secondary education, one can find a statement that the ‘vocative form’ is used to express appellation. However, the “nominative case” can also occasionally perform this function.Purpose. The purpose of this paper is to compare the morphological variability of appellation expressing codified in the Soviet handbooks and the accurate appellation expressing in dramas of the 1920s – 30s of the XX century. To find out the presence or absence of the pragmatic differences between vocative and nominative in this function is in the focus of our analysis as well.Methods. The methodological base of research is the discourse-analytical approach, within we compound discourse analysis method (to descry the designing new syntactic norm in the linguistic-didactic discourse of the end of the 1930s – the beginning of the 50s) and content-analysis method (to find out the real means of expressing appellation in social realists’ dramas of the 1920s – 30s of the XX century).Results. Theory about vocative as non-case and legitimization of the term ‘called form (vocative form)’ to denote it became dominant in all Soviet Ukrainian language handbooks for secondary and higher education. There are no remarks about another qualification in this grammatical category in the analyzed handbooks, and it evidences the monologue style of the Soviet linguistic-didactic discourse. The authors of these handbooks codify a double language norm to express an appellation – the vocative form and the nominative case. The thesis about nominative as a means to denote an appellation is usually formulated in the way of a superficial remark that may be apprehended by a recipient as upon the table fact. The study of the morphological manifestation of appellations in the drama of late 1920–30s created by the authors transmitting the official party ideology proves that vocative case predominates. Nominative to denote appellation has mainly a pragmatic effect or is one of the means of creating characters. Moreover, only in O. Korniychuk’s plays the use of morphological forms of appellations does not follow any regularities.Discussion. Spreading the nominative case to denote appellation in modern colloquial speech is conditioned by the complex of factors. On the one hand, it is a loosening of language norm in Soviet handbooks and on the other hand, it is the fact that morphological forms of vocative and nominative in plural nouns and singular nouns of neutral gender are homonymous. However, this thesis is needed verification on more comprehensive language material that represents different functional styles of the Ukrainian language.

Language as Poetry and Drama According to Benedito Nunes

Benedito Nunes was a Brazilian philosopher and literary critic who developed his activities in the second half of the twentieth and the first decade of the twenty first centuries. A graduate in law, he was, in the beginning of his intellectual career, an autodidact in philosophy, until he could attend Merleau-Ponty’s and Paul Ricouer’s courses in France, in 1960. His publications, ranging from didactic books to treatises and anthologies of essays, approach mainly topics of aesthetics and philosophy of art (particularly philosophy of literature). In this article special attention is given to two of his most relevant books: Passagem para o poético. Filosofia e Poesia em Heidegger [Passage to the poetic. Philosophy and poetry in Heidegger] – winner of 1987’s Prêmio Jabuti award – and O drama da linguagem. Uma leitura de Clarice Lispector [The Drama of Language. A Reading of Clarice Lispector]. Article received: April 23, 2021; Article accepted: July 30, 2021; Published online: October 15, 2021; Original scholarly paper

Discourse Act Contributing to the Linguistic Formulation from Word to Sentence: Albanian Children

In this argument, based in concrete observation for toddlers 2-4 years old, will be treated the case of lexical input of this age, used in the act of speech from the communication through special words- accompanied with extra-linguistic means,- from holophrases, to generating simple sentences, as special constructs of syntax. Primal phases of owning the language have already slowly started in the first years of their lives. The child follows the unstoppable road to understanding and enriching knowledge. As helping to our material will be included, except for their group and family life, didactic materials as well, in which part of our study were “Open and Find out” books, which are made of secret windows and puzzle books, which contain plenty of material that serves to the children’s speech-gaining act. The theory treating of the problem above will be mostly supported by Albanian language data, or by Albanian children – as native speakers of that mother language. The principal phases of owning the language have slowly started during the first years of his life. Now the child follows the unstoppable way to gaining and enriching his knowledge. The methodology followed in this material includes preschool children. During this phase the child articulates more lexical words than grammatical words. We noticed the phenomena when observing 14 children, who were selected from two age groups. The conversations of the different aged and gendered subjects were analyzed, as well as the vocabularies they owned. During this treatment will be shown linguistic features that children are prone to change from one phase of life to another. It’s also interesting to emphasize how even in the word and sentence producing phase, children are developed and skilled by using didactic books on them.

A Comparative Study on the Appreciation and Adoption of Dijian tushuo in China, Korea, Japan, and France

Dijian tushuo (帝鑑圖說; The Emperor's Mirror, Illustrated and Discussed) is a book compiled by Zhang Juzheng (張居正, 1525-1582), a great scholar during the late period of the Ming Dynasty of China. The book was made for the education of Wanli Emperor (萬歷帝, r.1572-1620), who rose to the throne at an early age. It contains 117 stories about the virtuous and evil deeds of previous emperors, complete with illustrations and relevant articles. After its presentation to the emperor in 1572, several editions of the book were produced by the end of the nineteenth century, and copies were distributed to neighboring countries like Korea and Japan and even to France via Jesuit missionaries. There are copies of more than twelve extant woodblock-printed and lithographic editions in East Asia, as well as copies reprinted with copper plates in France. Also, copies of the book with color illustrations remain in China and France. In Korea, colored illustrations of Dijian tushuo are kept under different titles such as Gunwang jwaumyeong (君王左右銘; The King's Motto) and Dohae yeokdae gungam (圖解歷代君鑑; The Mirror of Rulers throughout the Ages, An Illustrated Explanation) at the Gyeonggi Provincial Museum and the Jangseogak, the archive of the Academy of Korean Studies, respectively.<br/>In China, Dijian tushuo formed part of the education of the crown princes during the Ming and Qing Dynasties. More than eight different editions were made by the flourishing commercial publication industry during the two dynasties. In Joseon royal court, the book was recognized as one of the didactic books for the discipline of kingship. As for Japan, the shoguns of the Edo Bakufu used the book to advertise themselves as ideal rulers or to make Chinese royal palace genre paintings as an exotic hobby. Isidore Stanislas Henri Helman (1743~1809), a French engraver, made reprinted copies of the book amid Chinoiseries popularized in eighteenth-century France. The French edition reflects not only the public criticism of King Louis XVI and Marie Antoinette but also Helman’s implicit intention to receive financial support from Marie Louise Josephin de Savoie and the Count of Provence (later Louis XVIII), first in line to the throne at the time.<br/>Dijian tushuo was adopted in various countries in East Asia and Europe between the end of the sixteenth century and the early twentieth century, although the way it was used differed from country to country depending on their respective political, social, and cultural situations. However, all these countries had one thing in common– they had future rulers read the book. Perhaps, the fact that it was written for the education of the crown princes of China served as the stimulus for leaders and intellectuals alike. Studies on the ways in which books like Dijian tushuo were distributed as an aggregation of knowledge, information, and culture are thought to be significant and useful in identifying certain characteristics shared by diverse countries and in shedding light on differences in their political and social backgrounds and their art history.

Освоение педагогического потенциала культурно-образовательной среды города: опыт реализации проектной магистратуры

The purpose of the study is to present the methodological fundamentals of the development of cultural and educational environment of the city within primary education. We proved the necessity of revising training techniques for teaching culture under conditions of higher education. We explained top priority of orientation towards humanitarian, anthropological and axiological approaches to organization of mastering local lore at school and university. The cultural and educational environment of the city, i.e. the place, where a person was born, is considered as a tool for the interiorization of universal human values. The study gave reasons for importance of involving children in local lore activities at primary school age. Local lore is considered as a scientific basis for designing the content of school subjects; as a cultural training, activity aimed at learning about the heritage of one’s native city, preserving and enhancing the cultural level of the region, its inner potential; as a social activity aimed at developing civic mindedness. The article determined the possibilities of using local lore to teach moral and spiritual values to primary schoolchildren. The study described experience of creating and implementing a project-based research-based master’s degree programme at Saratov State University, aimed at training primary school teachers to use local lore materials in the educational process at school. The article reveals the structural and content components of the educational programme, the main forms and teaching methods. The article outlines the topics for student projects in the field of literary, linguistic, mathematical, and ecological local lore. We presented various methodological forms of incorporating local material in the class and extracurricular activities of younger students: compilation of interactive educational resources (books, reference books, albums, presentations, didactic problem books), preparation of quest games, virtual excursions, subject and intersubject projects. The article gives examples of cross-curricular competitions, mathematical problems with regional content. The priority area is the immersion of students (both students and schoolchildren) in the cultural environment of the city, region.

Mothers' discourse during shared reading of books relating to ‘positive’ and ‘negative’ emotions in different genres

BackgroundThe current study provides information about differences in parent–child discourse during shared book reading (SBR) surrounding narrative and didactic book genres about ‘positive’ (e.g. love, happiness) and ‘negative’ (e.g. anger and sadness) emotions. Research shows that characteristics of different children's book genres impact discourse during SBR, but narrative and didactic books have not been examined. Children's books often relate to the characters' inner mental and emotional states. Research has not explored parent–child conversations during SBR regarding different types of emotions, yet studies on other discourse contexts reveal that parents discuss ‘positive’ emotions differently than ‘negative’ emotions.MethodsParticipants were 26 mothers of 5‐ to 6‐year‐olds (M = 64.30 SD = 6.27). There were 18 boys and 8 girls. Eleven dyads received a narrative and didactic book on ‘positive’ emotions, and 15 dyads received a narrative and didactic book on ‘negative’ emotions. Interactions were video‐recorded and analysed. We examined the number of turns, initiations, general utterances and mental–emotional utterances.ResultsPrimary results revealed that mothers used more general utterances when reading both narrative and didactic books surrounding ‘negative’ emotions compared with books surrounding ‘positive’ emotions. Mothers used more mental–emotional utterances with a didactic book on ‘negative’ emotions compared with a narrative on ‘negative’ emotions and with a didactic book on ‘positive’ emotions compared to a narrative on ‘positive’ emotions.ConclusionsThis study highlights the importance of text selection for SBR and how it may impact the discourse. Mothers used didactic books for detailed conversations with their children. The simpler structure of the book may have facilitated the discourse about emotions. Mothers related more to anger and sadness compared with love and happiness. This may indicate that they feel they have to explain and teach their children about ‘negative’ emotions and how to cope with them, whereas positive emotions may be more implicitly understood.

Educación en salud

Objetivamos analisar a forma como o tema drogas é abordado em livros didáticos de biologia. Esta pesquisa apresenta abordagem qualitativa e utiliza o referencial da análise de conteúdo. A partir da análise, percebemos que a maioria dos trechos analisados é de abordagem biomédica, com apenas um de abordagem comportamental e dois de abordagem socioecológica. Também foram identificados trechos que contêm mais de uma abordagem, além de um erro conceitual relacionado à caracterização de uma espécie de fungo. Destacamos a importância de uma ampliação de abordagens para os temas saúde e drogas nos livros didáticos não se restringindo aos efeitos negativos e aos processos de adoecimento do corpo.

As conjunções integrantes em dicionários escolares para o Ensino Médio

Os dicionários são obras que descrevem o léxico em suas mais variadas formas. Por isso, assim como a Gramática, um de seus papéis é a apresentação de informações sobre as palavras gramaticais, cujo sentido está diretamente relacionado a sua função sintática. Esse é o caso das conjunções, elementos gramaticais geralmente usados na conexão de outros elementos e fundamentais para a coesão textual. Partindo desse contexto, este artigo tem como objetivo descrever as informações lexicográficas presentes nos verbetes das conjunções integrantes que e se dos dicionários escolares tipo 4 presentes no PNLD-2012. Para compreender o conceito de conjunção, discutimos as ideias de pesquisadores como Cunha e Cintra (2017), Bechara (2009) e Bagno (2012), além dos trabalhos de Pontes (2009) e Brasil (2012), para entender como se organizam os dicionários escolares. Essa pesquisa tem orientação qualitativa e se propõe a ser descritiva em sua análise de dados. Nossos resultados apontam que a maioria dos verbetes analisados apresenta orientação gramatical nas informações lexicográficas sobre as conjunções integrantes, abordando sua função sintática, como ocorre comumente nas gramáticas. Podemos perceber, ainda, que a abordagem gramatical dada às conjunções pelas obras analisadas é de orientação normativa, pautada em regras e nomenclaturas, o que dificulta a compreensão dos verbetes para leitores que não conhecem as normas da sintaxe, especialmente as relacionadas à construção dos períodos compostos.

A ânsia eterna, a violência, o silenciamento e o grotesco em Os Porcos, de Julia Lopes de Almeida

Julia Lopes de Almeida foi uma abolicionista do século XIX e uma das idealizadoras da Academia Brasileira de Letras. O objetivo da discussão é resgatar essa escritora, tomando como base o processo de silenciamento e violência que atinge as mulheres dentro e fora do âmbito literário e personificado por Umbelina, em Os porcos, escrito em 1903. A referida obra não faz parte do cânone, dos renomados manuais de literatura, dos livros didáticos, nem tampouco do conhecimento do grande público. Contudo ela reflete as mazelas sociais resultantes de anos de submissão e ausência de reconhecimento, sobretudo da crítica que fomenta, grotescamente, pontos cegos na escrita feminina na historiografia da literatura. O diálogo entre a violência ficcional sofrida pela protagonista do conto e a violência simbólica e empírica vivida pela referida escritora andam ombro a ombro com as inúmeras violações de direitos vivenciadas pelas mulheres até os dias atuais. O referencial teórico compõe-se, principalmente, por Woolf (1928), Telles (1988), Perrot (2005) e Colling (2004). Discutiu-se a representação dessa mulher que anseia sair do silenciamento, que, por sua vez, também é uma forma de violência.

Compêndio geografia para quarta série secundária (1938) de Aroldo de Azevedo sob a perspectiva da organização do trabalho didático

Este trabalho analisa o compêndio intitulado Geografia, 6ª edição (1938), destinado à quarta série secundária, de autoria de Aroldo de Azevedo. Objetivamos apreender o papel desempenhado por essa obra no ensino secundário. Para tanto, elegemos como categoria central a organização do trabalho didático, formulada por Gilberto Luiz Alves. No que se refere à metodologia, procedemos à revisão bibliográfica de trabalhos sobre a formação intelectual, experiência profissional e produção literária de Aroldo de Azevedo e de estudiosos da área da História da Educação e da legislação educacional pertinente. Verificamos que a obra analisada se trata de um compêndio, precisamente de um compêndio em transição, pois certas características evidenciam a aproximação com o manual didático.

ACESSIBILIDADE E AUDIODESCRIÇÃO: UM OLHAR PARA A APRENDIZAGEM DOS ESTUDANTES COM DEFICIÊNCIA VISUAL

O texto em tela tem como objetivo apresentar a audiodescrição de imagens estáticas de um livro didático como ferramenta de adequação pedagógica contributiva para o acesso às imagens por estudantes com deficiência visual. Enquanto escolha metodológica, trata-se de um ensaio teórico, pois traz, de forma dialógica, uma proposta de reflexão acerca do objeto de conhecimento elencado. Assim, a audiodescrição, como recurso de tecnologia assistiva pode ser um aporte para que professores, no ambiente escolar, garantam que estudantes cegos e com baixa visão tenham autonomia e empoderamento em atividades, exercícios e afins. Esse recurso de acessibilidade comunicacional pode ser compreendido como a descrição de toda e qualquer informação pertinente e essencial para que as pessoas com deficiência visual, ao mesmo tempo que as pessoas videntes, tenham acesso ao evento visual. Conclui-se que presença da audiodescrição nas imagens estáticas como ferramenta de adequação pode garantir a acessibilidade visual dos estudantes com deficiência visual, posto que promove equiparação de oportunidades para a erradicação do silêncio entre o texto e a imagem, tão comum nas escolas ao se tratar do estudante cego e com baixa visão.

In‐depth analysis of an RCD snubber applied to a DC‐DC boost converter

SummaryResistor‐capacitor‐diode (RCD) snubbers are traditionally used in practice aiming to maintain the stresses on semiconductors within safe operating limits. However, a serious drawback is the power lost in the resistor, which may affect the converter efficiency significantly. In this context, this work proposes a detailed procedure for the accurate design of an RCD snubber based on two additional key parameters that are not considered in typical guidelines provided in didactic books, that is, the forward recovery time of the main diode and the inductor current ripple. The impact of the maximum additional voltage spike on the switch is first assessed considering that it influences both the power dissipated in the snubber resistor and the current stresses on all semiconductors. A systematic optimization of the design is presented later on, considering that proper tradeoffs can be made among the type of main diode used in the converter, the maximum voltage spike on the switch, and the inductor current ripple as demonstrated mathematically. A dc‐dc boost converter operating in continuous conduction mode (CCM) is thoroughly analyzed so that is possible to derive a consistent methodology comprising all power stage elements. This study intends to shed new light on an old research topic, as well to investigate the snubber impact on the converter operation and overall performance. The effectiveness of the proposed approach is demonstrated experimentally employing a laboratory prototype rated at 200 W. The results clearly show that is possible to optimize the design as desired, with good overall performance over a wide load range considering all aforementioned aspects.

Teorías geográficas, técnicas cartográficas y diplomacia: Hans Steffen, un geógrafo prusiano en los Andes Australes

Hans Steffen, un destacado geógrafo prusiano (1865-1936) fue contratado por el Gobierno de Chile en 1889 como profesor de geografía para trabajar en el por entonces recientemente formado Instituto Pedagógico. A finales del siglo XIX, cuando Steffen ya había consolidado su posición profesional en Santiago, Chile y Argentina decidieron someter el litigio limítrofe sobre los Andes a un arbitraje internacional. En ese contexto, Steffen se involucró activamente en la preparación del documento que el gobierno chileno llevaría al diferendum. Esta presentación analiza las ideas, las teorías y las prácticas geográficas desarrolladas por Steffen para la conceptualización y la demarcación de la frontera entre Argentina y Chile a partir de los textos que produjo (diarios, libros didácticos, declaraciones diplomáticas, conferencias publicadas), las imágenes (mapas, fotos, bocetos, esquemas y notas de campo).