39,766 research outputs found
Plastic pollution in the ocean
Plastic pollution in the ocean was first reported by scientists in the 1970s, yet in recent years it has drawn tremendous attention from the media, the public, and an increasing number of scientists spanning diverse fields, including polymer science, environmental engineering, ecology, toxicology, marine biology, and oceanography. In the oceans, the threat to marine life comes in various forms, such as overexploitation and harvesting, dumping of waste, pollution, alien species, land reclamation, dredging and global climate change. The extremely visible nature of much of this contamination is easy to convey in shocking images of piles of trash on coastlines, marine mammals entangled in fishing nets, or seabird bellies filled with bottle caps, cigarette lighters, and colourful shards of plastic. Even without these images, anyone who has visited a beach has certainly encountered discarded cigarette butts, broken beach toys left behind, or pieces of fishing gear or buoys that have washed ashore
Graphing calculators in the teaching and learning of mathematics: a research bibliography
This review suggests that using graphing calculators in mathematics education can enable students to approach situations graphically, numerically and symbolically, and can support students’ visualisation, allowing them to explore situations which they may not otherwise be able to tackle (and thus perhaps enable them to take their mathematics to a more advanced level). In this way, using graphing calculators can lead to higher achievement among students, perhaps through increased student use of graphical solution strategies, improved understanding of functions, and increased teacher time spent on presentation and explanation of graphs, tables and problem solving activities (compared with students not using such calculators). The impact of the availability of this form of calculator on teaching methods and curricula appears to have been more limited, with teachers reportedly tending to use graphing calculators as an extension of the way they have always taught, rather than provoking any radical change in style of teaching or design of the curriculum
A new introductory quantum mechanics curriculum
The Institute of Physics New Quantum Curriculum consists of freely available
online learning and teaching materials (quantumphysics.iop.org) for a first
course in university quantum mechanics starting from two-level systems. This
approach immediately immerses students in inherently quantum mechanical aspects
by focusing on experiments that have no classical explanation. It allows from
the start a discussion of interpretive aspects of quantum mechanics and quantum
information theory. This article gives an overview of the resources available
at the IOP website. The core text is presented as around 80 articles
co-authored by leading experts that are arranged in themes and can be used
flexibly to provide a range of alternative approaches. Many of the articles
include interactive simulations with accompanying activities and problem sets
that can be explored by students to enhance their understanding. Much of the
linear algebra needed for this approach is part of the resource. Solutions to
activities are available to instructors. The resources can be used in a variety
of ways from supplements to existing courses to a complete programme.Comment: 10 pages, 2 figures, 1 table; submitted to the European Journal of
Physic
A survey of partial differential equations in geometric design
YesComputer aided geometric design is an area
where the improvement of surface generation techniques
is an everlasting demand since faster and more accurate
geometric models are required. Traditional methods
for generating surfaces were initially mainly based
upon interpolation algorithms. Recently, partial differential
equations (PDE) were introduced as a valuable
tool for geometric modelling since they offer a number
of features from which these areas can benefit. This work
summarises the uses given to PDE surfaces as a surface
generation technique togethe
Video summarisation: A conceptual framework and survey of the state of the art
This is the post-print (final draft post-refereeing) version of the article. Copyright @ 2007 Elsevier Inc.Video summaries provide condensed and succinct representations of the content of a video stream through a combination of still images, video segments, graphical representations and textual descriptors. This paper presents a conceptual framework for video summarisation derived from the research literature and used as a means for surveying the research literature. The framework distinguishes between video summarisation techniques (the methods used to process content from a source video stream to achieve a summarisation of that stream) and video summaries (outputs of video summarisation techniques). Video summarisation techniques are considered within three broad categories: internal (analyse information sourced directly from the video stream), external (analyse information not sourced directly from the video stream) and hybrid (analyse a combination of internal and external information). Video summaries are considered as a function of the type of content they are derived from (object, event, perception or feature based) and the functionality offered to the user for their consumption (interactive or static, personalised or generic). It is argued that video summarisation would benefit from greater incorporation of external information, particularly user based information that is unobtrusively sourced, in order to overcome longstanding challenges such as the semantic gap and providing video summaries that have greater relevance to individual users
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