Process Controller Essay Example | Topics and Well Written Essays - 250 words

Process Controller - Essay Example The most important of these requirements is safety. This is primary, in order to ensure the well being of the people in the plant and for its continued contribution to the economic development. The operating temperatures, pressures, concentrations, etc. should always be within allowable limits. Quality is also an important factor. A plant should be producing the desired amounts and quality of the final product. Moreover, the various types of equipments have constraints inherent to their operation. Such constraints should be satisfied throughout the operation of the plant. The plant must also conform to the market conditions that are the availability of raw materials and the demand of the final products. It should be as economical as possible in its utilisation of raw materials, energy, capital, and human labour, hence, operating at minimum cost and maximum profit, striking a right balance between both to give an optimal performance. Also, various federal and state laws may specify co nstraints on temperature, flow rates of effluents, etc. to be within certain limits, keeping environmental regulations in mind. (Stephanopoulos 3) All these requirements dictate the need for a good design, which is accomplished through proper selection of controllers, plant design parameters, etc. Different controllers have different effects on the response of the controlled process. The type of feedback controller to control the given process hence forms the first step of controller design. The second design question is â€Å"How do we select the best values for the adjustable parameters of the feedback controller chosen?† This is known as the Controller Tuning Problem. Various performance characteristics such as Overshoot, Rise time, Settling time, Decay ratio and frequency of oscillation of the transient could be used as the basic criteria, while designing. The designer must strike a subjective balance between the different

The American History Essay Example | Topics and Well Written Essays - 750 words

The American History - Essay Example There arose great tension between Great Britain troops and colonial militiamen in Lexington. April 1775 kicked off the armed conflict, and one year later, the rebels were waging the full-scale war for their independence. France joined to support the Continental Army to force the British to give up their power. Finally the British surrendered at Yorktown, Virginia, in1779, and the Americans won their independence, though fighting did not formally end until 1783. These were the founding fathers of America. Just after the revolutionary war, these men came with a political system that was entirely novel for an era in which monarchs ruled most countries around the world. Just after having being freed from the British Empire, the fledgling king would have no king at all. Instead, an elected head referred to as the President of the United States of America would be elected (Michener). The president would be the leader of the federal government, enforcing the laws of the land, and acting as the commander -in- chief of the armed forces. And yet, while the presidency has since become the emblem of the American way of life, the country might have gone in a very different direction before George Washington took the oath of office on April 30, 1789, many Americans envisioned a crown for the wildly popular Virginia planter. Washington refused, and so did the farmers of the Pennsylvania Avenue in Washington D.C., and a big mansion that would be called the White House. After Washington's reign as president then followed a series of others like John Adams, Thomas Jefferson, Abraham Lincoln, and Theodore Roosevelt all the way up to the current president who is actually the first black president of the United States of America. This constitution established America's national government and fundamental laws and guaranteed the basic rights for all of its citizens. The Constitution was signed on September 17th, 1787 by the delegates to the constitutional convention to the United St ates. In 1791, The Bill of Rights that guaranteed basic individual protections such as freedom of speech and religion became part of the Constitution.