The amplitude and frequency of such tides is affected by the moon's location as it revolves around the Earth. The gravitational pull of the moon creates a tidal bulge at the location directly beneath its location. Every two weeks or so, the moon aligns with the Earth and sun in a straight line -- the new and full moon phases -- resulting in the maximum gravitational force on our planet's oceans. These periods are referred to as spring tides..
http://d3fzrw9hngh8qa.cloudfront.net/glossary/CORECountries.mp4. According to a way of thinking about economies known as World Systems Theory, CORE countries are strong and wealthy countries that generate lots of wealth, and on which other countries depend. In the 14th century, Mongolia was a CORE country, and Italy was a peripheral country.
(plural inner cores) 1  Used other than as an idiom: see inner,â core. ( planetology) The solid material found in the centre of some planets at extremely high temperature and pressure, distinct from the liquid outer core.