Authors: Paul Kleinman
The Decline and Fall of the Ming Dynasty
The Ming Dynasty began to decline under the reign of Emperor Shenzong. When his chancellor, Zhang Juzheng, died, state affairs began to be neglected, and later, his army was defeated by the “Latter-Jin” regime. The last ruler was Emperor Weizong, whose reign was defined by corruption and extreme hardship due to natural disasters. In 1628, rebel forces began attacking. In 1644, Beijing fell to a rebel army. Emperor Weizong hanged himself, thus ending the Ming Dynasty.
Reading with Touch
Braille relies on the sense of touch rather than the sense of sight. While reading, you move your index finger from left to right over the text with one hand, while the other hand searches for the next line of text. The text is a series of raised dots arranged in cells, and there are sixty-four possible combinations for one cell.
Measuring Angles
The angle is defined by the theta symbol, θ. The length of the arc is represented by the lowercase letter
s
, and the radius of a circle is represented by the lowercase letter
r
. The lowercase letter
k
is used to represent a scaling constant, and that depends on the units of measurement in the problem. The basic formula for finding the value of an angle is:
The Asteroid Belt
Asteroids are bits of rock that were left over after the formation of the Sun and the planets. These asteroids are most often found orbiting the Sun between Mars and Jupiter. This area is known as the asteroid belt, and more than 7,000 asteroids have been discovered in it. The total mass of the asteroids found in the asteroid belt is less than the mass of the Moon.
Polder Dutch
Polder Dutch is a variation of Dutch spoken by the younger generation. In Polder Dutch (a term coined by Jan Stroop), diphthongs are pronounced with a wider mouth, and are pronounced lower. Polder Dutch seems to have begun around the 1970s, and originally it was middle-aged women and the upper-middle class who were pronouncing these diphthongs in this way. It has since spread.
The Economy of the Ming Dynasty
The economy of the Ming Dynasty showed an end of feudalism and the beginnings of capitalism. From the reign of Zhu Yuanzhang and onward, porcelain making was the major source of finance, and there was a wide interest in foreign commodities from both Europe and America. Urbanization and commercial metropolises also arose during this time in cities such as Beijing, Nanjing, and Yangzhou.
Grade II Braille
Grade II Braille is an extension of Braille used in English. Beyond just letters and numbers, it includes punctuation marks, composition signs, single-cell words, contractions, short-form words, and abbreviations. Whereas Grade I Braille used a cell to represent each letter, symbol, or number, in Grade II Braille, a single cell can represent whole words.
The Trigonometric Functions
In trigonometry, sine, cosine, and tangent are used to find the relation of the angles of a triangle to the sides of the triangle. The basic equations are:
The Milky Way
The Milky Way is the spiral-shaped galaxy that is the home to our solar system. Whereas the solar system revolves around one Sun, the Milky Way contains at least 400 billion other stars (with their planets and other objects in orbit). The Milky Way is just one of 200 billion galaxies that have been observed from Earth.