bluuebunny/crossref_metadata_2025 huggingface dataset:
Mineralogical and Chemical Characterization of Bajrawia Iron Ore, Sudan
Authors: Abbaker Ahmed Mohammedelmubarak , Moslim Eltahir Mohamed , Elsalmawy Montasir Sabbah El Din
Published: June 2021

In this contribution, the mineralogical and chemical characterization of Bajrawia iron ore is investigated. The chemical analysis was conducted using atomic absorption spectroscopy, X-ray Fluorescence, Energy Dispersive X-ray and titration. The mineralogical characterization was obtained by optical microscopy and X-ray diffraction. The physical properties such as densities, water content and porosity were determined. It was found that Bajrawia iron ore contains about 35.5% Fe and some impurities like phosphorus and silica. Goethite is the major iron mineral associated with minor contents of hematite, kaolinite and quartz. SEM photo showed that the main minerals are goethite, clay minerals and quartz. The ore has low density because it has high porosity degree. This type of iron ore is disseminated in rock matrix and would be difficult to process.
Shear Behavior in Beams Reinforced with Glass-Fiber Reinforced Polymer Bars (GFRPB) without stirrups
Authors: Daoud Osama , Fadul Ahmed
Published: June 2021

The behavior and shear strength of concrete beams reinforced with glass fiber-reinforced polymer (GFRP) bars was investigated. Total of six reinforced concrete beams without stirrups were constructed and tested up to failure. The beams measured 1400 mm long, 150 mm wide and 300 mm deep and were tested in two-points bending with constant shear span 350 mm in all tested beams, and shear span to depth ratio a/d 1.37. The test variable was the reinforcement ratio. The test beams included three beams designed as tension control (T.C) with GFRP bars, three beams designed as compression control (C.C) with GFRP bars. The test results were compared with predictions provided by ACI 440.1R-15 design guideline and proposed equations in the literature. The test results indicated that the relatively low modulus of elasticity of FRP bars resulted in reducing shear strength. In addition, shear strength provided by ACI 440.1R-15 guideline underestimate shear strength capacity in which proposed equations in the literature had given better prediction than ACI 440.1R-15. The failure mode in T.C beams is diagonal tension by bond failure not by rupture of FRP and C.C beams is shear compression by crushing of the web in extreme fiber.
بناء المعايير والاوزان لتقيم مشاريع التخرج لطلبة العمارة - (ج)
Authors: Siddig Mohamed Yagoub Ibrahim
Published: June 2021

Evaluation criteria for graduation projects of architecture students have a major role in helping students to generate innovative graduation project, so the paper aims to build standards and criteria to evaluate graduation projects of architecture students. These criteria These will be used as a tool to assist professors and educators to fairly assess and analyze all types of graduation projects, and to achieve the research goal a methodology divided into three phases will be followed Firstly, to extract and find a draft of the standards by studying the theoretical aspect of architecture, and studying the criteria for arbitration of graduation projects in which members of the jury are interested in the academic community, secondly it deals with the foundations of building standards, and the philosophy of adding criteria to standards, then criteria of standards when evaluating each type of project Different graduations in jobs Third, testing the criteria for evaluating and applying proposed graduation projects, by selecting different samples of graduation projects for the previous year and evaluating them by arbitrators from the professors of Architecture and Planning, and comparing the results from them with previous evaluation results, in order to find out their suitability and suitability to evaluate graduation projects. It has been reached that building standards and criteria assist professors and educators to a fair evaluation of graduation projects, and help the students in the design process of innovative architectural designs that achieve the greatest benefit.
Chloride Diffusion in Cementitious Pastes:
Comparative Study between OPC and Blended Cements Containing Natural Pozzolana and Slag
Authors: Hummaida Yousif , Mubarak Alaa
Published: June 2021

Chloride apparent diffusion coefficient (Dapp) of a porous media is an indicative of its capacity to resist chloride ingress. It is used to predict the service life of reinforced concrete structures. This paper presents experimental study to measure the effect of blended cement paste containing Sudanese Natural Pozzolana (SNP) from Bayuda Desert in the Northern State on Dapp by using Bulk Diffusion Test (Nord–Test NT–Build 443). Three mixes are investigated, each mix contains 3 specimens, the first mix is a reference mix with 100% Ordinary Portland Cement (OPC) compared with second mix having another containing 75%OPC:25%NP, third mix having 50%OPC:50%GGBS. All pastes have water binder ratio of 0.55. The Dapp of 50%OPC:50%GGBS is found to be 1.794*10-6 mm2/s which is lowest among the pastes. The Dapp for 75%OPC:25%NP is 2.80*10-6 mm2/s and the Dapp for 100%OPC is 3.145 *10-6 mm2/s which is the highest.
El Impacto de la Ley del Gran Canal Interoceánico de Nicaragua sobre los Pueblos Indígenas y Afrodescendientes de Nicaragua
Authors: Acosta María Luisa
Published: June 2021

Estado actualmente promueve el mayor megaproyecto en la historia contemporánea mundial, denominado Gran Canal Interoceánico de Nicaragua. El 13 de junio de 2013, la Asamblea Nacional de Nicaragua, aprobó sin consultar a los pueblos indígenas y afrodescendientes, la concesión a la Empresa Hong Kong Nicaragua Development (“HKND”); y el 7 de julio de 2014, HKND y el gobierno de Nicaragua anunciaron la ruta del Canal y la planificación de la construcción de varios sub-proyectos, los que en el istmo de Rivas, en las costas del Océano Pacífico, y sobre el Gran Lago de Nicaragua, o Cocibolca, perjudica a las comunidades indígenas: Salinas de Nahualapa, Nancimí, Veracruz del Zapotal, Urbaite de las Pilas y San Jorge Nicaraocalí; así como la construcción de un puerto de aguas profundas en tierras de la comunidad Kriol de Monkey Point , y Rama, de Punta de Águila/Bangkukuk Tai éstos, los últimos hablantes del idioma Rama. Según los estándares internacionales, el Estado al consultar debe actuar de buena fe; entregar la información técnica, los Estudios previos, e informar sobre los impactos que pueda causar la obra; promover una participación efectiva del pueblo indígena por medio de un proceso de diálogo y discusión, culturalmente adecuado según sus costumbres y tradiciones; y acordar sobre los beneficios compartidos, como compensación al uso de sus territorios y recursos naturales. Todo lo anterior hasta llegar al consentimiento libre, previo e informado de estos pueblos y comunidades.
Autonomía regional y tierras comunales del Caribe Sur nicaragüense ante el proyecto canalero
Authors: Ayérdiz Danny Ramírez
Published: June 2021

La autonomía regional del Caribe nicaragüense está fuertemente asentada sobre las formas especiales y ancestrales de tenencia de la tierra indígena y afrodescendiente, toda vez que estas formas especiales son ideológica, cultural e históricamente distintas a cualquier otra que el Estado nacional ha reconocido en las leyes ordinarias. Entonces, y amén de la simbiosis indisoluble tierra comunal-autonomía regional, las leyes del canal no sólo ponen de manifiesto una evidente tensión con los derechos étnicos sobre la tierra per se, si no con todo el régimen autonómico cuya construcción jurídica está dada por un Estado que constitucionalmente se declara multiétnico.
Comparison of Postoperative Anatomy Using Anatomic Total Shoulder Arthroplasty Versus Soft-Tissue Balancing Total Shoulder Arthroplasty
Authors: Truntzer Jeremy , Vopat Bryan , Schwartz Joel , Anavian Jack , Barnds Brandon L. , Blaine Theodore A. , Green Andrew
Published: June 2021

Background:

The importance of anatomic reconstruction of the proximal humerus on shoulder biomechanics and kinematics after anatomic total shoulder replacement (aTSR) has been highlighted by a number of investigations. The humeral head designs of current-generation shoulder arthroplasty emphasize either anatomic or soft-tissue balancing total shoulder arthroplasty (sbTSR) philosophies. The purpose of this study was to compare the postoperative anatomy of TSR systems used to treat primary glenohumeral osteoarthritis.

Methods:

This was a matched cohort study of 60 patients treated with either press-fit aTSR or sbTSR by two shoulder surgeons. The analysis of postoperative true AP radiographs was performed to calculate multiple representative anatomic parameters of the TSR.

Results:

A significant difference was observed in the average measurements between the sbTSR and aTSR designs about the humeral head center offset (5.2 ± 0.4 mm versus 3.9 ± 0.3 mm; P = 0.02), implant–humeral shaft angle (0.3 ± 0.3 varus versus 1.7 ± 0.3 valgus, P < 0.001), and humeral head to tuberosity height (8.8 ± 0.4 mm versus 6.2 ± 0.4, P < 0.001), respectively. No significant difference was observed in the average measurements between the two systems' designs regarding the head–shaft angle (133.4° ± 0.8° versus 135.0° ± 1.0°, P = 0.16) and the relation of humeral head to lateral humeral cortex (0.15 ± 0.6 mm inside the lateral cortex versus 0.19 ± 0.6 outside the lateral cortex; P = 0.69), respectively.

Conclusions:

Despite differing design philosophies of these systems, and some notable differences, the absolute differences between the measured anatomic parameters were small and not likely clinically relevant. Anatomic and soft-tissue balancing humeral arthroplasty implants can both reliably reconstruct proximal humeral anatomy.
The Relationship Between Writing Anxiety and Writing Self-Efficacy of Students Learning Turkish as a Foreign Language
Authors: BAŞKAN Ahmet
Published: June 2021

The study aimed to determine the relationship between writing anxiety and writing self-efficacy of students learning Turkish as a foreign language. The study sample consisted of 247 international students at B1 and B2 levels at the Turkish Education Application and Research Center of a foundation university. The Writing Anxiety Scale for Learners of Turkish as a Foreign Language, developed by Şen and Boylu (2017), was used to determine students’ writing anxiety. There were 13 items and two factors on the scale: Action-Oriented Anxiety and Environmental Oriented Anxiety. The Writing Self-Efficacy Scale for Turkish Students who Learn Turkish was developed by Büyükikiz (2012) to determine the students’ writing self-efficacy. This two-factor scale had 16 items and explained 56.85% of the variance. The research was designed based on the relational screening model. SPSS 21.0 package programs were used to analyze the data. The study results indicated a significant positive relationship between writing anxiety and writing self-efficacy of students who learned Turkish as a foreign language. Besides, there was no significant difference between the Turkish learners’ scores from the writing anxiety scale and their language level.
Een integrale veiligheidsmonitor als hulpmiddel bij het sturen op beleidsdoelen: theorie, praktijk en geleerde lessen
Authors: Kroesbergen Ike , Rijkers Arthur
Published: June 2021

An integrated safety monitor to assist in the governance on policy goals: theory, practice and lessons learned

This article provides a case description of the development of an integrated safety monitor for the governance on policy goals. The governance on these safety goals took place in cooperation between eight municipalities and Police, Justice, Fireworks, Health Care providers for addiction or domestic violence and partners in incident and crisis management. Two problems were adressed. The first problem is that the evidence on process and results of monitoring from data to interpretation and policy choices in cooperation with different safety partners, is scarce. The second problem is that monitoring of a wide range of indicators on integrated safety is also scarce. In our case, the gathering of data and the interpretation of these data together with all the partners formed a cyclical process. This corresponds with the theory of governance developed by Ansell and Gash in a meta-analysis in 2008. The starting conditions were made clear. The design of the monitoring process was translated into themes of working sessions with a group of policy advisors, giving them a structure for the governance on the policy goals. This group developed a layered set of indicators. These set of indicators was broken down in the four policy goals as well as in different steps in the safety chain. Indicators from different registrations of the safety partners were combined with indicators about the perception of safety measured by a representative sample of the residents. The layered set of indicators was supportive in the discussion about a well balanced monitoring on prevention, signals, interventions and effect. The data were interpreted together with the safety partners. This was helpful in creating a joint perspective on safety problems and in the discussion about meaningful policy actions. The challenge now is to persevere in the cyclical process from data to interpretation and shared understanding about policy goals.
Problemas con el lenguaje científico en la escuela: un análisis desde la observación de clases de ciencias naturales
Authors: Galagovsky Lydia R. , Bonán Leonor , Adúriz-Bravo Agustín
Published: June 2021

The present report describes examples and reaches conclusions concerning failures in class communication between science teachers and their students. A general situation characterised as «empty discourse» could be observed through analysing classes recorded by students belonging to last year in Science Teaching degrees. We inspect some implications of our observations for pre-service teachers’ training.
L'ensenyament dels conceptes de força centrípeta i força centrífuga. Una proposta inspirada en la història mecànica
Authors: Casadellà Reig Josep , Miró C.
Published: June 2021

Textbook authors use many types of resources to teach centripetal acceleration, centripetal force and centrifugal force. They are resources between an intuitive and a formal perspective. We try to make a review, not exhaustive, of three points of view and also to present a new one supported on an original Newton’s idea, and which could present some advantages when teaching and learning these concepts.
La astronomía en textos escolares de educación primaria
Authors: García Barros Susana , Martínez Losada Cristina , Mondelo Alonso Matilde , Vega Marcote Pedro
Published: June 2021

In this paper we analyse the way in which the study of Astronomy is dealt with in Primary School textbooks. Moreover, we study how the topic should be approached at this school level.
Análisis de la transición de la física clásica a la relativista desde la perspectiva del "cambio conceptual"
Authors: Toledo B. , Arriassecg I. , Santos G.
Published: June 2021

Interviews about special relativity are realized with students of a Modem Physics course. The results of the interviews’ analysis suggest that conceptual change doesn’t mean a substitution of classic physics conceptions by the relativistic ones but that there is an interactive coexistence of both.
¿Cuándo un contenido académico tiene significado para el alumno? Implicaciones didácticas
Authors: Jiménez Gómez Emma , Marín Martínez Nicolás
Published: June 2021

The importance of identifying the prior ideas of students on a given content is based, among other reasons, on the need to accommodate the teaching processes to the cognitive peculiarities of the pupils. However, individuals tend to develop ideas or conceptions only for some academic purpose, that is to say for those that are meaningful to them. Hence the need to establish some observable criterion that permits classification of the content teaching purpose by their degree of meaning level, whose science education interest resides in the utilization of accepted teaching techniques with the said meaning level.
El trabajo práctico en la enseñanza de las ciencias: una revisión
Authors: Barberà O. , Valdés P.
Published: June 2021

This article is a review about the effectiveness of practicáis in science education at the secondary and tertiary levels. Through more than one hundred references, the authors conclude solid arguments have not been provided to justify the great deal of material and human resources needed for the implementation of this educational tool. In spite of these disappointing findings, the authors do not deny the central role of practicáis in science education, and they justify these negative results by invoking the great complexity of the subject, the ambiguity that surrounds the term «practicáis», and an unsuitable methodology that researchers use to measure their effectiveness. Finally, some plausible solutions to the problem are suggested, such as the characterisation of the educational objectives of practicáis, or the use of a qualitative evaluation methodology.
Introducción a la genética en la enseñanza secundaria y bachillerato: II. ¿Resolución de problemas o realización de ejercicios?
Authors: Ayuso G. E. , Banet Hernández Enrique , Abellán T.
Published: June 2021

In this paper we analize the level of knowledge students have at different educational levels (15-18 years), about some basic concepts related to genetic inheritance. The strategies developed by students when solving, successfully, genetic problems have also been studied.The results show the difficulties in learning through problem-solving activities. Consequently, very often, their posings (even those of cause-effect approach) allow them to find the right solution by applying the correspondent algorithm. As a conclusion, some suggestions to change the students’ position on genetic problems are presented.
Una reflexión curricular sobre la enseñanza de la estructura de la sustancia en la formación de profesores de química
Authors: Ferro V. R. , González Jonte R. H. , Cruz Z.
Published: June 2021

In this article we reconsider the manner of teaching the concept of structure of substance in order to improve the teaching performance of chemistry teachers. In order to achieve this goal we modify the habitual, static presentation of substance to relate it to thermodynamic and kinetic aspects. In this way we facilitate a better understanding of the chemical change.
Aplicación didáctica de la balanza "pesaoro" de Arquímedes
Authors: Salvat Altés A. , Sánchez Real José
Published: June 2021

In this article two methods are exposed —with its practical application in the school— in order to discover whether the golden crown of King Illeron III from Siracusa (III c. bC) was totally made of gold or, on the contrary, the goldsmith who had made it, changed by silver part of the gold given by the King.
Geología, ciencias de la tierra, ciencias de la naturaleza: paisaje de un aprendizaje global
Authors: Anguita G.
Published: June 2021

Notwithstanding its profound contributions to modern Science, Geology importance in Science Education has been (and still is) continuously dwindling. This situation is universal and has historic roots. At the same time, a reintegration of Geology with other sciences has been taking place, resulting in the Earth Sciences. The Earth Sciences concept is better adapted than Geology to new conceptual advances such as Systems Theory, Catastrophe Theory, or Chaos Physics. Nevertheless, caution is of essence when adapting those physico-mathematical theories to a Science whose methods are not mainly experimental but descriptive and historie. One of the present lines of advance in Earth Science Education is based on courses in which biologists and geologists together analyse Earth and Life systems. Viewing towards a farther horizon, we can find courses on Science integrating Biology, Chemistry, Geology and Physics concepts included in the new school curriculum. Although highly commendable in theory, the scheme is probably deemed to result in no real progress towards integrating Science, since it is not accompanied by deep changes in University curricula.
Epistemología, caos y enseñanza de las ciencias
Authors: Luffiego García Máximo , Bastida M. F. , Ramos F. , Soto J.
Published: June 2021

In this article it is maintained that modern science is going through a critical period where its epistemological assumptions and the use of a parcelling and reductionist methodology are questioned. This will surely have important implications in the teaching of the sciences, perhaps because the world today demands above all an epistemological change in the people who, within a few years, will occuppy the posts in the production and reproduction of scientific and technical knowledge
Identificación de competencias y características deseables en el profesorado de ciencias de EGB
Authors: Rodrigo M. , Agra Cadarso M. J. , Gómez Crespo M. A. , Morcillo Ortega Juan Gabriel , Vidal M. , Unamuno M. P.
Published: June 2021

This article offers the vision held by some groups of teachers on various qualities taken as important for a Science Teacher of Primary Education, as well as the opinion on to what extend those qualities are found in this type of teachers.
Contribución de la historia y de la filosofía de las ciencias al desarrollo de un modelo de enseñanza/aprendizaje como investigación
Authors: Gil Pérez D.
Published: June 2021

After the fiasco of the «Iearning by discover y» orientation and the serious limitations of the «reception learning» paradigm, a new consensus is emerging on the nature of mathematics and science learning as a construction of knowledge. These constructivist approaches have taken explicitly into account contemporary views in philosophy of science as an epistemological base for a conception of learning as a conceptual change. Teaching strategies oriented to produce conceptual changes have been developed with promising results, but serious difficulties have also appeared. Our contribution will try to show that those difficulties are due to a still insufficient consideration of the nature of science in the teaching strategies. Consequently, we shall propose some modifications of these strategies, taking more carefully into account the relationship between the nature of science and the nature of learning.
Aprendizaje por descubrimiento: principios y aplicaciones inadecuadas
Authors: Barrón Ruiz A.
Published: June 2021

This article deals with a critical analysis of the practical applications of discovery learning. To this end, the principles on which we have reconstructed that theory of learning are used, according to a constructivist foundation of cognitive activity as a conjectural activity, mediated by sociocultural orientations. This article is based on previous research by the author (Barrón 1989, 1991a, 199 I b). After defining and establishing the theoretical principles, the inadequate practical applications of discovery learning are examined, derived, in some cases, from an empiricist concept of discovery, and in others, from a «scientific reductionism», «individualist», or «rnechanistic» concepts of learning by discovery.
Las ideas de los profesores de ciencias sobre la formación docente
Authors: Martínez Losada Cristina , García Barros Susana , Mondelo Alonso Matilde
Published: June 2021

In this paper we investigate novel teachers' notions and practice regarding their conceptions about the need to receive a specific teaching formation, and the most suitable way to achieve this formation.
Nouvelles tendances dans la Didactique de la Chimie et rôle du Comité pour l'Enseignement de la Chimie de l'IUPAC
Authors: Chastrette M.
Published: June 2021

We call attention to the enormous spreading undergone by the didactic of chemistry in the last few years and comment on some of the trends that are significant in this field from the point of view of the author. We also comment on some of the projects developed by the committee for teaching chemistry in the IUPAC.
El concepto de masa en la física clásica: aspectos históricos y didácticos
Authors: Domènech A.
Published: June 2021

Different definitions of mass in classical physics are discussed in basis to their physical representation. The following questions are adressed: a) the quantitas materiae problem, b)dichotomy between inertial and gravitational masses and, c) didactic implications of the different definitional modalities.
¿Qué pueden aportar a los enseñantes los diferentes enfoques de la didáctica de las matemáticas? (segunda parte)
Authors: Brousseau Guy
Published: June 2021

In the first part of this paper we raised the question of whether a customized theory of the didactics of mathematics was legitimate and presented and overview of such a theory. This second part analyses the contribution from and constraints to the classical approaches and social practices on which they rely, and discusses the relationship between mathematics and its didactics.
Una premisa para el cambio conceptual : el cambio metodológico
Authors: Segura D.
Published: June 2021

This paper outlines some of the differences between preconceptual and Aristotelian methodology and relates the origin of preconcepts to the ordinary conception of Science underlying in textbooks and laboratory manuals. A classroom strategy aimed at changing the prevailing methodology and developing a new basis for conceptual reconstruction is put forward.
Factores psicológicos de insucesso na resoluçao de problemas de física: uma amostra significativa
Authors: Neto Antonio José
Published: June 2021

A study of the influence of some pertinent psychological factors on physics problem -solving performance is attempted. The special cases of conceptual, verbal, and procedural information and cognitive development are analysed.
Evaluación de un plan instruccional dirigido hacia la evolución de las concepciones de los estudiantes acerca de circuitos eléctricos
Authors: Andrés María Maite
Published: June 2021

This paper presents the results of a research with high school students. The work began with the diagnosis of conceptions in the students about the electrics circuit. Then it evaluated the effect of the instructional proposition. The instruction intended to stimulate the conceptual conflict and produce the conceptual change in the students.
Instrucción para la transición cognoscitiva : el caso de física
Authors: Bascones J.
Published: June 2021

Results of the evaluation of an instructional system which take account of how past experiences and knowledge influence perception, comunication and learning are presented. Experimental activities, problem solving, and discussion period for contrasting previous and new learning have been emphasized in the instructional design. Instructional strategies such as conceptual maps, Gowin's heuristic V and problem solving have been used. The instructional system was evaluated with a sample of 76 secondary school. The selection was based on previous knowledge of optics and the determination of misconceptions in cognitive structure of the same population. Results show relevant differences in tests between controlled and experimental groups.
El aprendizaje del álgebra escolar desde una perspectiva psicológica
Authors: Kieran C. , Filloy Yagüe Eugenio
Published: June 2021

This paper describes some of the main contributions of research to the growing knowledge of the cognitive processes which the learning of algebra in secondary schools involves. The continuous attempts of researchers to develop a theory on the teaching/learning of algebra are also discussed. Finally, some future trends in the teaching/learning of algebra are mentioned.
Usos y abusos de la Historia de la Física en la enseñanza
Authors: Sánchez Ron J. M.
Published: June 2021

This paper contributes to the debate concerning the introduction of the History of Science —more specifically the History of Physics— into Secondary Education and University curricula.
Circuitos eléctricos : una aplicación de un modelo de enseñanza-aprendizaje basado en las ideas previas de los alumnos
Authors: Varela P. , Manrique del Campo Mª J. , Favieres A.
Published: June 2021

In this paper we wish to present the practical realization of the constructivist view of knowledge, carried out with an experimental type of methodology. The phases of the work have been: the detection on preconcepts, the elaboration of the curriculum, the design of didactic materials and the evaluation of the results obtained. The research has been carried out on the topic «electric current» at the level of 2nd. year of B.U.P.
Estudio piloto sobre el efecto del ordenador en la adquisición de conceptos matemáticos en alumnos de 5º y 7º de EGB
Authors: Bautista García-Vera Antonio
Published: June 2021

In this paper we try to give an overview of the uses of computers in education. Then we check the effectiveness of Logo environment in a teaching method based on a problem solving approach. Finally the results of a statistical analysis are discussed.
Análisis de contenidos en óptica geométrica
Authors: Perales Palacios F. Javier
Published: June 2021

This work reports on the findings of a content analysis in geometric optics. Such analysis has been carried out through two dimensions of the scientific content structure, the substantive and curricular ones. For that purpose, a consensual criterium out of nineteen textbooks of physics including the topic mentioned has been adopted. The first type of analysis leds to identify the «key» concepts and their relations in a hierarchized conceptual map. On the other hand, the curricular analysis resulted in a proposal of sequentiation for the implied contents. At the end, didactic consequences of the procedure described are discussed.
La metodología científica y la enseñanza de las ciencias : unas relaciones controvertidas
Authors: Gil Pérez D.
Published: June 2021

In this paper we make a review of the relationship between science learning and scientific methodology. We try to show that coherent results of several lines of educative research are contributing to the rising of a science learning model as a conceptual and methodological change, in which students work has the characteristics of research.
La realimentación en la evaluación en un curso de laboratorio de Física
Authors: Colombo de Cudmani L. , Pesa de Danón M. , Salinas de Sandoval J.
Published: June 2021

Methods of continous evaluation with feedback as well as those of discontinuous evaluation without it are discussed. Even though at first sight the former offered advantages upon the latter, and considering their costs in terms of time and effort when working with large groups, it was thought advisable to make a measurement leading to some objective judgement. An experience with students attending a Physics Laboratory Course, 2nd. year Engeneering, was carried out, taking two sample groups and two reference groups, each one constituted by 50 students. After planning and carrying out the experience, results are analized and conclusions drawn which  appear to show that the disadvantages implied by continuous evaluation with feedback are largely compensated by the results obtained.
Inteligencia artificial y pensamiento real
Authors: Hernán Francisco
Published: June 2021

This paper focussses on the analysis of Hardy's point of view, «at bottom, all mathematicians think in the same way», and looks for its implications on teaching. Research on Artificial Intelligence provides some hints which suggest that a new approach to the relationship between concepts and processes.
El Bachillerato Internacional y su enseñanza de las Ciencias y de las Matemáticas
Authors: Renaud G.
Published: June 2021

This paper introduces the aims of International Baccalaureate and, more specifically, concerning science education and mathematics. The different curricula are also described, as well as the education system. Finally, reference is made to the 'pedagogical workshop' character of the International Baccalaureate.
La astronomía en el Bachillerato : diferentes enfoques
Authors: Fernández Uría E.
Published: June 2021

In this article the authors defend the introduction of Astronomy into secondary education, given the cultural and educative richness of this science. Different teaching procedures are briefly analysed, among which the use of Astronomy as a source of questions and problems of didactic value is emphasized. Different examples are offered showing the variety of possibilities than can be explored by teachers.
Como fomentar los principios de actividad y creatividad al aplicar el método científico en la Escuela. Un ejemplo para la formación de maestros
Authors: Lillo Beviá José
Published: June 2021

The results of an experiment about the permeability of soils is commented and proposed to three groups of students of the Teacher Training School in Pontevedra. A guide for the activity is not given, but with some indications. The students design the experiment and its parts, criticize their own activity and correct their mistakes. It is verified that the richess of ideas given by the students exceeds the previsions which an ordinary teacher would do in designing the guide of a given experiment. The student does not only verify the experiment guide, but he is the designer and the critic of the investigating process. The results obtained encourage us to practise an active, creative and inexpensive methodology in the training of future teachers.
Elaboración de multimedia para la enseñanza de la química
Authors: Casanova J. , Alberola A.
Published: June 2021

As a consequence of several agreements between Departament of the Science Section of the University of Valladolid and zeachers of several french universities who where trying to produce a few documents about the teaching of Chemistry of the kind «teaching aids», a research group was born with the name of GRIDUQUIVA. We give information about all the plan to make teaching aids by the GRIDUQUIVA.
De la evolución de las especies a la evolución de las ciencias
Authors: Doncel Manuel G.
Published: June 2021

In the ocassion of Darwin's centenary, toulmin's evolutive epistemology in stressed, within other modern epistemological currents, which are considered as fixist or evolutive in character. This epistemology distinguishes different levels of scienctifical change, and uses the Darwinian model to explain continuity and.change in the scientifical disciplines. The dynamical concept of rationality which emerges from this study, can be useful for teaching sciences in a more humanistic way.
Rudimentos históricos do associativismo e do sindicalismo dos trabalhadores em educação no Estado de São Paulo (1978-2017)
Authors: Bauer Carlos , Gindin Julián
Published: June 2021

Em Rudimentos históricos do associativismo e do sindicalismo dos trabalhadores em educação no Estado de São Paulo procuramos trazer um amplo mapeamento da organização dos trabalhadores em educação paulistas, tendo como base uma periodização iniciada com o ciclo das greves de 1978, se estendendo até o ano de 2017, momento este marcado por uma reforma trabalhista que alterou drasticamente a legislação que vigorava desde os idos das décadas de 1930-40. Houve ainda a preocupação de incluir os segmentos menos estudos ou pouco considerados nas pesquisas sobre esta temática na área da educação, como é o caso dos professores universitários, os docentes do ensino privado e os trabalhadores técnicos administrativos do sistema educativo.
Selected health issues related to high altitude trekking
Authors: Prószyńska-Bordas Hanna , Baranowska Katarzyna
Published: June 2021

The aim of the paper was to investigate health aspects of high altitude trekking such as preparation for the physical exertion during trekking at high altitude, the impact of mountaineering on the daily life before and after the expedition, the effect of high-mountain conditions on health and well-being. It was found that in the pre-departure period trekkers commonly train to ensure that they are physically fit for the expedition. They train alone or under the supervision of a trainer. Self-prepared workouts may turn out to be insufficient due to the lack of appropriate training plans. The most challenging aspects of high altitude trekking for the body include carrying too heavy equipment, dealing with illegibly marked routes, wearing inappropriate clothing, having an unbalanced diet, not having enough water, which can lead to dehydration and infections. Misconduct by other people poses a risk. The specific type of effort involved in mountaineering requires balanced nutrition in terms of both micro- and macro-elements. To find the right combination, one has to either experiment or seek advice from a dietitian. However, relatively few people consult a nutrition coach. Among sanitary problems, the most serious one is inappropriate human waste disposal, the resulting lack of drinkable water. Some of the observed problems result from insufficient regulations regarding the conduct in the mountains and from trekkers’ lack of awareness regarding good practices in such extreme conditions.
Online resources of the World Tourism Organization: fostering knowledge and raising awareness in society during the COVID-19 pandemic
Authors: Kozińska Katarzyna
Published: June 2021

The purpose of the article is to explore and describe the resources made available by the United Nations World Tourism Organization (UNWTO) during the COVID-19 pandemic and discuss their role in fostering knowledge and promoting awareness in society. The resources are examined using a conceptual model of website evaluation proposed by Li and Wang (2010), which has been adapted to be applicable to the organizational context of UNWTO. The findings show that the UNWTO website resources can be divided into two categories: resources related to the COVID-19 pandemic, e.g. information about existing special groups, and resources connected with the core mission of the UNWTO, e.g. important events from before the pandemic or the organization’s main goals. There are new interactive tools, developed specifically in relation to the pandemic, with relevant data for those involved or interested in the tourism sector. The resources are freely available, easily accessible, abundant, varied and highly informative. The UNWTO website is a gateway to knowledge, providing information about, reasons for and effects of relevant actions of the organization, e.g. raising awareness of the importance of both the pandemic problem but also tourism itself, securing considerable funding for the tourism sector by making world leaders aware of the facts and the importance of tourism, or promoting safe travel measures and encouraging actions aimed at accelerating the recovery of the tourism sector.
A Summary of the H. IRVING PRATT Ocean Race Handicapping Project
Authors: Kerwin Justin E. , Newman J. N.
Published: June 2021

Research has been carried out to provide improved engineering methods for handicapping ocean racing yachts. A velocity prediction program (VPP) has been developed to simulate the sailing performance of a given yacht, in terms of parameters which represent its hydrodynamic and aerodynamic characteristics. Race results have been analysed to validate the VPP, and also to optimize time allowance formulae. An electro-mechanical hull measuring device has been developed to facilitate the measurement of hull offsets in a complete and precise manner. These results of the Pratt Project already have found application, especially in the USYRU Measurement Handicapping System (MHS).
Geometry of Sailmaking
Authors: Andresen Ted
Published: June 2021

The aerodynamic force developed by a sail depends on the sail's shape. The horizontal cross-sectional shape is of particular importance in determining sail performance. Two parameters for describing the shape are presented and three methods of measuring the shape are outlined. The current practice of using edge rounding and broadseaming is de­scribed and four solutions to the problem of creating faster shapes are presented. First, the pragmatic approach which uses an interative search for the fastest edge round and broadseam pattern is examined. Three other approaches that model the sail as a mathematical surface and use geometry to compute the patterns are presented. Here the sail is treated as a stack of horizontal arcs with precisely defined shapes. In one method, a path excess equation is used to calculate the luff round for a mainsail. Another approach plots the geodesic paths on the sail's surface and computes the seam­by-seam broadseaming. Lastly, an integral method is employed to find the broadseaming for a sail based on the Penguin mainsail. Measurements of the sail made by this method are presented and discussed.
Experimental Analysis of Five Keel-Hull Combinations
Authors: Gerritsma J. , Keuning J. A.
Published: June 2021

Model tests with five different keels in combination with one particular hull form have been carried out in the Delft Towing Tank. The variations include a plain deep keel, a keel-centre board, a plain restricted draft keel,a "Scheel" keel and a "winglet" keel. Based on the experimental results performance predictions are given for a 63 ft yacht for windspeeds up to 25 knots. The measured side force and resistance as a function of heeling angle, leeway angle and forward speed are used to analyse the relative merits of the considered keel-hull combinations.
LIMITATIONS OF THE PANEL REGRESSION MODEL APPLICATION: THE EXAMPLE OF THE WESTERN BALKAN COUNTRIES
Authors: Stanić Stanko , Baškot Bojan
Published: June 2021

Panel regression model may seem like an appealing solution in conditions of limited time series. This is often used as a shortcut to achieve deeper data set by setting several individual cases on the same time dimension, where cross units visually but not really multiply a time frame. Macroeconometrics of the Western Balkan region assumes short time series issue. Additionally, the structural brakes are numerous. Panel regression may seem like a solution, but there are some limitations that should be considered.
AN INSIGHT INTO POTENTIAL FISCAL IMPLICATIONS OF THE GREAT LOCKDOWN FROM THE PERSPECTIVE OF SMALL STATES
Authors: Primož Pevcin
Published: June 2021

The Great Lockdown has caused severe economic distractions to the majority of world countries, and de-globalization trends have started to increase. Globalization was to an extent beneficial for smaller economies, and it was one of the factors contributing to the rise in the number of countries around the world during the last few decades. According to the perceived larger openness and vulnerability of smaller states, it is thus expected that those countries are hit much harder by the economic contraction, as their outputs are much more volatile in relation to the economic cycles. In this context, the paper intends to investigate the exposure of European states to the current lockdown, where the focus is particularly on assessing the fiscal impacts of the lockdown. The main research question is whether there are any differences regarding the fiscal functions of government between smaller and larger states. This is addressed through the cross-national comparative investigation based on data for 44 European countries; and we specifically assess how fiscal activities of government differentiate among smaller and larger states. The results of the study suggest that the effect of the size of the state does not affect the consumption spending of government, but the size variable matters for the transfer expenditures. This piece of research would like to add to the development of the discipline of small state studies, in particular to the issue of their vulnerability and changing global economic environment.
INVESTMENT AND ECONOMIC GROWTH: THE EXAMPLE OF BOSNIA AND HERZEGOVINA
Authors: Bjelić Jelena
Published: June 2021

An investment is a factor of the economic growth and a mandatory constituent in the majority of development models. This study analyzes the impact of the gross investment on the economic growth in Bosnia and Herzegovina (BiH) for the period 2005-2017, and provides the assessment of the interdependence of investment and a newly added value in industry. The relationship between the foreign investment and the economic growth is also included. The dependent variables are the GDP growth rate and the added value in industry (as % of GDP). The independent variables are the total investment rate (as % of GDP) and the foreign investment rate (as % of GDP). The hypothesis is that the gross investment and the foreign investment are positively correlated with the GDP growth rate. The investments contribute to a higher newly added value in industry. The results show that the gross investment is a significant factor of the economic growth because there is a high significance and positive correlation between the observed variables (the total investment and the GDP growth). This shows that the investment growth stimulates the economic growth in Bosnia and Herzegovina. But the dynamic analysis as an investment-GDP ratio shows oscillations. The impact of investments on the share of the newly added value in industry is insignificant and negative. The results of the dynamic analysis are similar. The relationship between the variables of the foreign investment rates and the GDP growth is significant and positive. Although the foreign investments are not sufficient, they still contribute, to a certain extent, to the economic growth of BiH.
THE IMPACT OF DEBT-SERVICING BURDEN ON HOUSEHOLD EXPENDITURE IN NIGERIA: A CASE OF EKITI STATE SENATORIAL DISTRICTS
Authors: Ditimi Amassoma , Matthew Ikechukwu Ogbuagu , Damilola Fasina
Published: June 2021

This study employs binary logistic regression technique to explore the impact of household debt-servicing burden on expenditure patterns in South-West geo-political region of Nigeria, using Ekiti State as a case study. Questionnaires were randomly distributed to 2500 households, and the results unveil that households with high income, large family-size and heads within the age group (40 and above) were more susceptible to debtburden. In addition, the paper highlighted that indebtedness compromises the quality of nutrition and health status of household members. Based on the above findings, we conclude that high indebtedness and debt burden trajectories cause deleterious effects on household consumption patterns and overall economic well-being. Thus, household heads should inculcate fiscal discipline which promotes saving culture and averts future shocks that could emanate from precautionary demands. Second, debt providers should regulate loans in cognizance to household repayment capacity and other stipulated policies which break the vicious cycle arising from over-indebtedness, install stability and spur economic development.
“Its Hand around My Throat”. The Social Rendering of Borrelia
Authors: Soncco Ritti
Published: June 2021

This paper builds on biomedical and anthropological discourses of microbial agency to explore the important opportunities this discourse offers medicine, politics, anthropology, and patients. “Borrelia burgdorferi”, often termed “the Great Imitator”, is an ideal candidate for this discussion as it reveals how difficult it is to speak about Lyme disease without engaging with microbial agency. Based on 12-months research with Lyme disease patients and clinicians in Scotland, this paper offers a social rendering of the bacteria that reveals epistemologies of illness not available in medical accounts: the impact of social and psychological symptoms such as body dysmorphia, depression, shame, post-traumatic stress disorder, and suicide-related deaths on patients’ illness narratives. Divorcing agency from the bacteria silences these important patient narratives with the consequence of a limited medical and social understanding of the signification of Lyme disease and the holistic methods needed for treatment. This paper furthermore argues that the inclusion of patient worldings of Borrelia acting in the medical renderings offers a democratic determination of what the illness is. Finally, building on Giraldo Herrera and Cadena, I argue for a decolonization of Borrelia, exploring how the pluriverse both takes the epistemologies of patients seriously and reveals medical equivocation.