Quantitative study on teacher quality: case of middle grades mathematics

This quantitative study examines whether and how different proxies of teacher quality such as cognitive type of teacher knowledge, coursework and certification are associated with student achievement. In the context of this study, the cognitive type of teacher content knowledge refers to the amount and organization of mathematical facts and procedures, concepts and connections, and models and generalizations in the minds of teachers. Teachers were tested using a specifically designed Teacher Content Knowledge Survey. Teacher preparation and teacher demographic characteristics, such as teaching experience, teacher certification, teacher coursework were collected and analyzed with respect to the cognitive type of teacher knowledge and student achievement. The type of teachers' content knowledge was assessed and tested for correlation with student achievement on the state-mandated standardized test using multivariate methods including, but not limited to, tests for variance and independence, and correlation analysis

CONTENT INTERACTIVITY AND CONTENT COMMUNICATION IN ENGINEERING OF ONLINE MATHEMATICS METHOD CLASS

In today's world, current revolutionary changes are associated with the intensive use of digital technologies in many spheres of human life, which democratize knowledge and access to open education. The ICT is increasingly implemented in the daily lives of individuals and the society. We are witnessing the formation of a new phenomenon - a global virtual learning community, which today includes more than one billion users. And the numbers continue to grow. Along with this, the market of online educational services is steadily growing. To meet the demands of the market, content development, content interactivity and content communication play important role in the engineering of online learning. In this paper, we will consider some of the approaches that will help to enhance content interactivity, such as cognitive visualization and other emerging techniques, for example, video streaming, screencasting, and gamification. We will also discuss different formats of content communication.8-2

Un estudio cuantitativo del conocimiento del contenido del maestro de matemáticas y su “saber actuar” en el aula

El objetivo de este estudio fue medir el conocimiento del contenido matemático del maestro de secundaria y su relación con el “saber actuar” del maestro. La pregunta de investigación es: ¿Qué tan asociados están los tipos cognitivos del conocimiento matemático con el “saber actuar” del maestro? Un estudio correlacional se desarrolló para establecer la relación entre estos dos tipos del conocimiento del maestro. Dos encuestas se aplicaron a 70 maestros de secundaria en la frontera norte de México. Una encuesta mide el conocimiento del contenido matemático del maestro (TCKS) y la otra examina el “saber actuar” (KtAS) del maestro

Etude de diodes lasers pour des applications métrologiques de la rétro-injection optique

Le phénomène de « self-mixing » (interférences à deux ondes dans le milieu actif d’une diode laser) est utilisé pour des applications métrologiques telles que la mesure de distance, de déplacement ou de vitesse. Dans ces dispositifs, une diode laser émet un faisceau en direction d’une cible. Une partie de l’onde lumineuse est réfléchie en direction du laser et perturbe la puissance d’émission. L’information métrologique recherchée est alors déterminée en traitant ces variations de puissance. Les principales caractéristiques de ces capteurs sont leur simplicité de mise en oeuvre, leur auto-alignement et leur faible coût. Dans la première partie (chapitres I à III), les limitations intrinsèques des interférences par self-mixing dues à la source laser sont étudiées. En particulier, nous déterminons la limite de portée de nos capteurs. En effet, la mesure de distance ou de déplacement par self-mixing est un système de détection cohérente. Comme pour les interférences classiques, les interférences par self-mixing possèdent donc une limitation fondamentale liée à la longueur de cohérence de la source utilisée en présence d’une cible. La seconde partie (chapitres IV à VI) a pour objectif de déterminer les critères prépondérants au choix de la source laser à utiliser pour chaque application métrologique du self-mixing. Ainsi, dans le quatrième et le cinquième chapitre, le comportement et la stabilité du mode longitudinal lasant d’une diode laser Fabry-Perot sont étudiés précisément avec et sans cible. La théorie semi-classique utilisée pour y parvenir est plus complète que celle présentée au premier chapitre. Il ressort que parmi les diodes lasers Fabry-Perot existantes, les diodes lasers multi-puits quantiques émettant autour de 800 nm sont celles qui couvrent le mieux les besoins des applications du self-mixing. Le chapitre VI présente différentes structures de cavité laser moins conventionnelles, susceptibles d’être intéressantes pour les applications du self-mixing. En particulier, l’utilisation d’une diode laser DBR à trois électrodes pour la télémétrie a permis d’obtenir une résolution de 0.5 mm de 20 à 60 cm. Enfin, nous présentons un télémètre contrôlé en fréquence optique dont les premiers résultats (résolution de 50 µm à 10 cm) sont encourageants pour la suite de son développement. ABSTRACT : The self-mixing interference is used for sensing applications like distance, displacement or velocity measurements. In such a set-up, interference occurs into the laser cavity between the beam inside this cavity and the beam back-scattered from a mirror-like or a rough target in front of the laser. Variations of the optical output power caused by this interference can be used to determine relative or absolute distances. In the first part of this manuscript (chapter I to III), self-mixing limitations due to the laser source are exhibited. Like for classical interference, the phenomenon can only be used for a target located at a distance smaller than the half coherence length. However, the self-mixing effect is quite different from classical interference as the coherence properties of the laser source are modified by the distance to the target and its reflection coefficient. The range of a relative or absolute distance sensor, developed in our laboratory, is then determined in terms of the spectral characteristics of laser sources. In the second part, the choice of the laser sources is optimised in function with each sensing application of the self-mixing effect. In chapter IV and V, the stability and the spectral behaviour of Fabry-Perot laser diode are analysed. The proposed semiclassical theory shows that multi-quantum well lasers emitting around 800 nm are the best choice for both self-mixing applications. Chapter VI presents different exotic laser structures which can be of great interest for self-mixing sensors. A 3 electrodes DBR laser diode has been used for distance measurement, a resolution of 0.5 mm being reached for a range between 20 to 60 cm. Finally, a new self-mixing range finder has been designed with a real-time chirp control, using an all-optical fibre Mach-Zender interferometer. A resolution of 50 µm has been obtained at a distance of 10 cm

QUALITATIVE STUDY OF SECONDARY MATHEMATICS TEACHERS' NOT-KNOWING WHILE SOLVING GEOMETRIC REASONING TASKS

Not-knowing is an underexplored concept defined by an individual's ability to be aware of what they do not know as a means to plan and more effectively face complex situations. This qualitative study focuses on analyzing students' ability to express their "not-knowing" while completing tasks and reflecting periodically. It becomes evident rather quickly that these students have difficulty expressing their not-knowing. Through transcription analysis, reflection coding, and interviews, four recurring themes emerge that could possibly determine why students have difficulty expressing their not-knowing. These four themes are deflection, student pressure, heuristic sense, and fractured knowledge. Each one of these themes will be discussed followed by a conclusion of their overall importance in relation to a students' ability to express not-knowing.147-15

SECONDARY SCHOOL MATHEMATICS TEACHERS' DISPOSITION TOWARD MISTAKES: CROSS-CULTURAL MIXED METHODS STUDY

The reported mixed methods study focused on exploration of mathematics teachers' dispositions toward errors in two countries - Mexico and USA. More specifically, this study addressed borderland secondary teachers' dispositions toward mistakes in teaching and learning mathematics. An explanatory sequential method design was used that involved collecting quantitative data first and then explaining the quantitative results with in-depth qualitative analysis. The instrument - Error Orientation Questionnaire (EOQ) - was used to collect quantitative data on teachers' disposition toward errors in the context of their own learning and their students learning. Following up on EOQ, the semi-structured interview was used to collect qualitative data. Two research questions guided the study. First, we were interested in what dispositions toward mathematical mistakes do secondary teachers in the US and Mexico have. The second question addressed ways the interview aimed at teachers' dispositions toward errors helped to explain the quantitative results.The reported mixed methods study focused on exploration of mathematics teachers' dispositions toward errors in two countries - Mexico and USA. More specifically, this study addressed borderland secondary teachers' dispositions toward mistakes in teaching and learning mathematics. An explanatory sequential method design was used that involved collecting quantitative data first and then explaining the quantitative results with in-depth qualitative analysis. The instrument - Error Orientation Questionnaire (EOQ) - was used to collect quantitative data on teachers' disposition toward errors in the context of their own learning and their students learning. Following up on EOQ, the semi-structured interview was used to collect qualitative data. Two research questions guided the study. First, we were interested in what dispositions toward mathematical mistakes do secondary teachers in the US and Mexico have. The second question addressed ways the interview aimed at teachers' dispositions toward errors helped to explain the quantitative results.188-19

Narrative analysis of college students' inconsistecies in representing duality of infinity

Interpreting students? views of infinity posits a challenge for researchers due to the dynamic nature of the conception. There is diversity and variation among the students? process-object perceptions. The fluctuations between students? views however reveal an undeveloped duality conception. This paper seeks to examine college students? conception of duality in understanding and representing infinity with the intent to elucidate strategy that could guide researchers in categorizing students? views of infinity into different levels. Data for the study were collected from N=69 college pre-calculus students at one of the southwestern universities in the U.S. using self-report questionnaire and interviews. Data was triangulated using multiple measures analyzed by three independent experts using self-designed coding sheet to assess students? externalization of the duality conception of infinity.223-23

Caracterización de las prácticas sociales asociadas a la génesis de la inducción matemática: Un estudio exploratorio en estudiantes de ingeniería

Este trabajo pretende caracterizar las prácticas sociales asociadas a la génesis de la inducción matemática para dar sentido o significado a la inducción matemática. Primeramente, se hizo una revisión bibliográfica en torno a la problemática de la inducción matemática. Después, se efectuó un análisis histórico-epistemológico de la génesis de la inducción matemática comprendiendo dos épocas: la época de los siglos anteriores al siglo XVI y la de los siglos XVI y XVII. Basándonos en la aproximación teórica de la socioepistemología se identificó la práctica social asociada a la inducción matemática: la demostración. Considerando esta práctica, se analizó la existencia de elementos útiles para lograr un rediseño del discurso matemático escolar considerando al estudiantado de ingeniería (varias). En esta exploración cuatro estudiantes y dos docentes participaron. A través de un cuestionario exploramos las dificultades que el alumnado encuentra al resolver problemas de inducción matemática. Se concluye que la inducción matemática es un método de demostración importante en las matemáticas, pero debido a la práctica social de la demostración asociada a su génesis se infiere que su resignificación es muy compleja e inapropiada para llevarla al aula de estudiantes de ingeniería. Por ello, se recomienda un análisis histórico-epistemológico del siglo XVIII a la fecha para considerar el rediseño del discurso escolar

A stochastic design optimization methodology to reduce emission spread in combustion engines

This paper introduces a method for efficiently solving stochastic optimization problems in the field of engine calibration. The main objective is to make more conscious decisions during the base engine calibration process by considering the system uncertainty due to component tolerances and thus enabling more robust design, low emissions, and avoiding expensive recalibration steps that generate costs and possibly postpone the start of production. The main idea behind the approach is to optimize the design parameters of the engine control unit (ECU) that are subject to uncertainty by considering the resulting output uncertainty. The premise is that a model of the system under study exists, which can be evaluated cheaply, and the system tolerance is known. Furthermore, it is essential that the stochastic optimization problem can be formulated such that the objective function and the constraint functions can be expressed using proper metrics such as the value at risk (VaR). The main idea is to derive analytically closed formulations for the VaR, which are cheap to evaluate and thus reduce the computational effort of evaluating the objective and constraints. The VaR is therefore learned as a function of the input parameters of the initial model using a supervised learning algorithm. For this work, we employ Gaussian process regression models. To illustrate the benefits of the approach, it is applied to a representative engine calibration problem. The results show a significant improvement in emissions compared to the deterministic setting, where the optimization problem is constructed using safety coefficients. We also show that the computation time is comparable to the deterministic setting and is orders of magnitude less than solving the problem using the Monte-Carlo or quasi-Monte-Carlo method

Anatolia, Turks and cultural living together culture in the historical romants Of Tasos Athanasiadis

Çağdaş Yunan edebiyatında roman ve özellikle de tarihsel roman türünde en çok eser veren Yunan yazarları, 30 Kuşağı içinde yer almaktadır. Bu dönem romanlarında, tarihsel olaylar yazarların bakış açısıyla okuyucuya yansıtılmaktadır. 30 Kuşağı yazarları içinde önemli isimlerden biri de Manisa Salihli doğumlu olan Tasos Athanasiadis’tir. Yazar, Kurtuluş Savaşı yıllarında ailesiyle birlikte Yunanistan’a göç etmiştir. Çok sayıda tarihsel roman yazmış olan yazarın eserleri Yunanistan sınırları dışında da büyük ilgi görmüştür. Yazarın dikkat çeken romanlarından biri, Ta Pedya Tis Niovis (Niobe’nin Çocukları) romanıdır. Dört ciltten oluşan romanın ilk iki cildi Türkiye’de, yazarın memleketi olan Salihli’de geçmektedir. Yazar Salihli’yi çocukluk anılarındaki güzellikleriyle okuyucuya aktarmaktadır. İzmir, Manisa ve Salihli’de yer alan mekân isimlerine, bölgede bulunan kasabalara ve çevre tasvirlerine ayrıntılarıyla değinmektedir. Hayranlıkla anlattığı bu bölgede paylaşılan yaşamı, yarattığı güçlü roman kahramanlarıyla zenginleştirerek, farklı bir olay örgüsü yaratmıştır. Roman, Türkler ve Rumların aynı coğrafyada barış ortamında geçirdikleri yılları, ardından Yunan ordusunun Batı Anadolu’yu işgaliyle başlayan savaş yıllarını, savaşın Türk ve Rumların günlük yaşamına etkilerini ve yenilginin ardından yaşanan göçü ele almaktadır. Romanın incelenen bölümlerinde mekân Batı Anadolu bölgesidir. Yazarın otobiyografik bilgilerine ve kurgulama yeteneğine dayanarak kaleme aldığı Ta Pedya Tis Niovis romanı, roman çözümleme yöntemlerinden yararlanarak incelenmiş ve yazarın, Türkleri nasıl yansıttığı, Türk ve Rumların sosyal yaşantısının nasıl verildiği, roman mekânı olarak Anadolu’yu nasıl tanıttığı imgebilim verilerinden faydalanarak incelenmiştir.Novel and especially historical novel in contemporary Greek literature Greek authors who publish works of the genre,located within 30 generations.İn this novel period,historical events are transmitted to the reader from the authors' perspective,One of the important names of the 30 generation writers was Thasos Athanasiadis who was born in Manisa Salihli.The author emigrated to Greece with his family during the war of liberation.He has written a number of novels, and his work has received much attention outside the borders of Greece. One of his notable novels is Ta Pedya Tis Niovis (The Children of Niobe).The first two volumes of the novel take place in Salihli, where the author was born, and the novel consists of four volumes.The author conveys Salihli to the reader with the beauties of his childhood memories.The site names in İzmir, Manisa and Salihli are mentioned in detail with respect to the towns in the region and their depictions of the environment.He created a different plot by enriching the life shared in this region, which he told with admiration, with the powerful novel heroes he created. The peaceful years spent by the Roman, Turks and Greeks in peace in the same geography, followed by the years of war that began with the invasion of the Greek army in Western Anatolia,it handles the effects of the war on the daily life of Turks and Greeks and the migration after the defeat.In the examined parts of the novel, the place is Western Anatolia.The novel of Ta Pedya Tis Niovis, based on the author's autobiographical knowledge and ability to construct,novel analysis methods and how the author reflects the Turks, the social life of the Turks and Greeks how was given and how Anatolia was introduced as a place of novel was examined by utilizing imagology data