The open field system was a system of agriculture in which large fields were divided into strips that were farmed by individual peasants. This form of farming predominated in Europe from the middle ages until the 1800s.Know More
In the open field system, the farmers did not own the land they farmed, according to "Story of Farming" at History 101. Instead, they managed this land during the growing season, but had little control over their strips of farmland the rest of the year. The peasants paid for the right to a strip of land to farm, and they paid taxes on the food they grew on this land. Yet even after paying for the right to the land, the peasants (or serfs) had little say in its management. Serfs were required to work the land for a set amount of time each day, and their crops were often prescribed by the landowners from whom they leased the land.
The size of the strip of land each peasant farmed was defined in acres. An acre was measured by the amount of area that a single farmer could plow in a single day.
The open field system declined in use due to soil depletion and more individualized methods of farming. Peasants planted the same crops year after year to make a living; however, this ran the soil dry of essential nutrients, such as nitrogen. Gradually, the open field system shifted to a more-regulated form of crop rotation, in which fields were planted in three-year rotations. This system helped push agriculture toward the modern model of individual land-owning farmers.Learn more about Agriculture
Closed-loop and open-loop systems are two different control types. Control theory is an interdisciplinary branch of engineering and mathematics that deals with the behavior of dynamical systems with inputs. Systems in which the output quantity has no effect on the processes' input quantity are open-loop control systems. Systems in which the output quantity and negative feedback affect the processes' input quantity are closed-loop control systems.Full Answer >
In the biological world, an open system is one in which materials and energy are transferred between organisms and the exterior environment. In an open system, there is some type of boundary that allows energy or materials to cross over for the purpose of growth and change.Full Answer >
Farmers most commonly feed pigs soybean or corn meal that has been mixed with dried whey, and they also add some vitamins and minerals, such as limestone and dicalcium phosphate to the food. Pigs can eat both plant and animal products, and they also need to drink water. Farmers ultimately plan their pigs' diets based on factors like age, size, the temperature outside and the housing method used.Full Answer >
More than 150 billion animal are killed each year for human consumption, and over 100 million animals are killed for laboratory purposes in the United States. These numbers do not reflect animal deaths from shelters, zoos or blood sports.Full Answer >