The Passing of Print

This paper argues that ephemera is a key instrument of cultural memory, marking the things intended to be forgotten. This important role means that when ephemera survives, whether accidentally or deliberately, it does so despite itself. These survivals, because they evoke all those other objects that have necessarily been forgotten, can be described as uncanny. The paper is divided into three main sections. The first situates ephemera within an uncanny economy of memory and forgetting. The second focuses on ephemera at a particular historical moment, the industrialization of print in the nineteenth century. This section considers the liminal place of newspapers and periodicals in this period, positioned as both provisional media for information as well as objects of record. The third section introduces a new configuration of technologies – scanners, computers, hard disks, monitors, the various connections between them – and considers the conditions under which born-digital ephemera can linger and return. Through this analysis, the paper concludes by considering digital technologies as an apparatus of memory, setting out what is required if we are not to be doubly haunted by the printed ephemera within the digital archive

Monitoring of lubricant film failure in a ball bearing using ultrasound

A lubricant-film monitoring system for a conventional deep groove ball bearing (type 6016, shaft diameter 80 mm, ball diameter 12.7 mm) is described. A high-firequency (50 MHz) ultrasonic transducer is mounted on the static outer raceway of the bearing. The transducer is focused on the ball-raceway interface and used to measure the reflection coefficient of the lubricant in the "contact" ellipse between bearing components. The reflection coefficient characterizes the lubricant film and can be used to calculate its thickness. An accurate triggering system enables multiple reflection measurements to be made as each lubricated contact moves past the measurement location. Experiments are described in which bearings were deliberately caused to fail by the addition of acetone, water and sand to the lubricant. The ultrasonic reflection coefficient was monitored as a function of time as the failure occurred. Also monitored were the more standard parameters, temperature and vibration. The results indicate that the ultrasonic measurements are able to detect the failures before seizure. It is also observed that, when us,ed in parallel, these monitoring techniques offer the potential to diagnose the failure mechanism and hence improve predictions of remaining life

M101: The Pinwheel Galaxy

This Hubble Space Telescope image of M101 showcases a spiral galaxy's well-known features. The text describes the features that are common to all spiral galaxies. In the accompanying educational activity, In Search of...Spiral Galaxies, students investigate the structure of spiral galaxies through a level 1 inquiry activity using the images and text from the lithograph and other resources. A level 1 inquiry activity can help prepare students to become independent thinkers. Educational levels: Middle school, High school

Jupiter's Red Spot Jr. lithograph and In Search of...Monster Storms associated classroom activity

This lithograph traces the emergence and color change of an Earth-sized storm on Jupiter. The storm appears to be the same color as Jupiter's trademark Great Red Spot and has been dubbed Red Spot Jr. In the accompanying educational activity, In Search of...Monster Storms, students compare Jupiter's storms with those of Earth through a level 1 inquiry activity using the images and text from the lithograph and other resources. A level 1 inquiry activity aims to prepare students to become independent thinkers. Educational levels: Middle school, High school

Amazing Space: Cat's Eye Nebula (NGC 6543) Lithograph

This lithograph features Hubble Space Telescope images and includes text that describes and explains the images. There is also an accompanying inquiry-based classroom activity entitled “In Search of the Complex Structures of Planetary Nebulae.” This activity is designed to encourage the development of research skills and independent thinking. Available online as well as hardcopy. Educators can access the lithograph PDF files on the Web site and print the materials for use in their classrooms. Educational levels: High school, Informal education, General public

Estrategias de enseñanza para la educación cívica y ciudadana en el siglo XXI

Uno de los retos que los educadores de la educación cívica en Europa deberán afrontar en el Siglo XXI es el uso de estrategias educativas que involucren de modo activo a los alumnos. En la actualidad abundan las estrategias didácticas; sin embargo, no todas son capaces de promover el aprendizaje para una participación activa en la sociedad. Las investigaciones más recientes apuntan hacia los siguientes rasgos fundamentales para la pedagogía de la educación cívica: fomento del aprendizaje mediante la experiencia; integración intencional de los valores, que deben ser explicados y defendidos por los educadores; fomento del pensamiento crítico y de la reflexión, a la vez que se anima a los alumnos a la elección personal y a la defensa de sus valores; creación en el aula de un clima que favorezca el aprendizaje de una participación activa en el ámbito social. Estas estrategias de la educación cívica son las más adecuadas para conseguir que los estudiantes sean ciudadanos democráticamente participativos