An analysis of different representations for vectors and planes in ℝ3

The purpose of this paper is to present an analysis of the difficulties faced by students when working with different representations of vectors, planes and their intersections in \(\mathbb {R}^{3}\). Duval’s theoretical framework on semiotic representations is used to design a set of evaluating activities, and later to analyze student work. The analysis covers three groups of undergraduate students taking introductory courses in linear algebra. Different types of treatments and conversions are required to solve the activities. One important result shows that, once students choose a register to solve a task, they seldom make transformations between different registers, even though this facilitates solving the task at hand. Identifying these difficulties for particular transformations may help teachers design specific activities to promote students cognitive flexibility between representation registers.     

Refining Students’ Explanations of an Unfamiliar Physical Phenomenon-Microscopic Friction

Research in Science Education - The first phase of this multiphase study involves modeling of college students’ thinking of friction at the microscopic level. Diagnostic interviews were...     

Reflections on obesity,exercise,and musculoskeletal health

Obesity is a disease that has become an epidemic in economically developed countries,and manifests itself at increasing rates in economically developing countries.Obesity is associated with a variety of comorbidities,such as metabolic disease,diabetes,cardiovascular diseases,and musculoskeletal disorders,all resulting in tremendous costs to health care systems around the world,a reduced capacity for work,and reduced quality of life for people with obesity,coupled with physical inactivity,thereby producing a vicious circle of inactivity-induced diseases that enhances obesity.