In this module you will study the motion of a vibrating string under undamped and damped conditions. There are interactive exercises to link everyday experiences with mechanics and mathematics. In particular, you will derive the equation which governs the motion of a vibrating string; study the motion of a vibrating string in a vacuum and in a fluid; compare real experimental data with theoretical predictions. Integrating the concepts of higher math with their applications in science and engine
The wondrous flight of millions of monarch butterflies from their roosts in the Sierra Madre mountains of Mexico has long captured the imagination of scientists, nature lovers and tourists. Each spring, the butterflies begin their remarkable journey north. They travel thousands of miles on a trek that provides them with optimal breeding conditions and ultimately ensures the survival of the species. This video segment from Nature captures the butterflies' spring awakening. Run time 03:02.
Biomes Interactive Site
The distribution of plants and animals around the world is anything but random. Instead, it is a result of the interplay of individual environmental tolerances of species and the environmental conditions, especially variations in temperature and precipitation. These interactions result in biomes, the categories into which ecologists organize similar communities of plants, animals, and the environmental conditions in which they live. This interactive resource adapted from NASA features some of th
Radioactive Decay Events Model
The EJS Radioactive Decay Events Model simulates the decay of a radioactive sample using discrete random events. It displays the number of events (radioactive decays) as a function of time in a given time interval. You can change the initial number of nuclei, the decay constant and the time interval for the event distribution.
The Horn of Africa has been experiencing exceptional droughts over the last decade. Using data collected from the NOAA POES satellite, changes in the severity of the drought conditions in the Horn and around the world are shown.
Lecture 4 [slides]: SQL, Continued
MySQL. SQL. MySQL types. Indexes, constraints. MySQL Functions. JOIN. Race conditions. INSERT ... ON DUPLICATE KEY UPDATE. Transactions (InnoDB). Locks (MyISAM). CSV.
Accounting at the London School of Economics: Opportunity Lost?
Given the aims of the founders of the London School of Economics, it is not surprising that accounting should have been taught at the School from soon after its establishment. An early focus on teaching practical accounting, with professional practitioners as teachers, was gradually supplanted by approaches informed by the economics of decision-making in conditions of scarce resources. By the 1930s, the Department of Business Administration provided an intellectual basis for thinking about finan
Securing Financially Sensitive Environments with OpenBSD
This thesis investigates the use of a free, open source
UNIX-based operating system in providing security features
to a financially sensitive business function such as a
We start by examining some of the main security features
(such as the pf firewall and systrace policies) which are
included with the operating system, how they work and how
such features can be used within a financial environment.
We then examine possible probl
La traite négrière
A partir du VIII siècle, environ des esclaves africains ont été vendus en Afrique du Nord et Arabie. Du XVIe au XIXe siècle, le commerce des esclaves ou la traite négrière a pris de l'ampleur : Ce furent d'abord les Portugais et les Espagnols qui s'adonnent à ce trafic. Plus tard, les Français, les Anglais, les Hollandais et les Allemands en firent de même. En Afrique des millions d'hommes et de femmes ont ainsi été faits prisonniers, transportés par bateaux et vendus comme esclaves
Right Triangles and Trigonometric Functions
In this video, the instructor talks about trigonometric functions as they relate to right triangles. He defines each function and how to find it using the different sides of right triangles. Then, he does example problems using the definitions of the trigonometric functions defined at the beginning. There is a buzzing sound in the background of this video, but the instructor is still able to be heard well.
Biology Mitosis vs. Meiosis
In this lesson, mitosis and meiosis are compared in terms of DNA replication, the number of divisions, the presence of synapsis, the number of daughter cells, and the numbers of chromosomes in the products and function. Only a partial lesson.
Run time (3:23)
Important Body Parts
An introduction to important body parts and their function for young school age children. It teaches about the parts that are inside our body, including the brain, heart, lungs, kidneys, and liver. Run time 04:51.
In this video from Vegas PBS, host Brian Wignall and two butterfly experts discuss butterfly species commonly found in the Nevada wilderness. Among the topics they talk about are the best time of year to see butterflies in Nevada, the means by which they protect themselves from predators, how weather conditions and daylight affect their flight, their longevity, and the distances some travel to and from their wintering grounds. Closed captioning included. Run time 04:35.
Weather Barometers : What Does a Barometer Measure?
A barometer measures the pressure of the atmosphere on the earth or the weight of the atmosphere pressing down towards the earth. Learn how high pressure means clear skies and good weather, while low pressure generally means cloudy, stormy conditions with information from a television meteorologist. Video is short and good quality and
How the Kidneys Work
This is brief, computer-animated video of an overview of the kidneys and their function in the human body.
This is a brief (01:10) video using computer animation that discusses the kidneys and how they function.
How the Body Works : The Pancreas
This is a short, narrrated video (01:30) about the function and structure of the pancreas.
Reviews the structure and function of the blood vessels. Computer animation and video with narration. Grades 7-12. 2:16.
This is a brief explanation/overview of functions in Calculus. The video explains what critical points are in a function.
Biology of Plants
The video gives a nice overview of the process of photosynthesis and then continues with the biology of plants - function, reproduction and life. Run time 17:42.