A Review of the Main Temperature Sensors for Control System and Assignment

A Review of the Main Temperature Sensors for Control System and Summary of the Typical Sensors for Measurement of Rainfall - Assignment Example Thermocouples are widely used because they are reliable, simple to use, and have a relatively lower price compared to other sensors (Seaton & Leach, 2005). Thermocouples are self-powered, thus eliminating the use of a separate or an external power supply to the sensors. They are durable when they are chosen appropriately for a designed application. Ibrahim and Coupland confirm that the thermocouple sensors are used in applications that handle very high temperatures such as incinerators. A thermocouple is a temperature transducer, which operates on a principle that unlike conductive materials is capable of generating current when they are joined (Setback effect) (Jianwei Shen & Shen, 2009). Such devices are made by joining two wires that are made of alloys (different metals) joined at one end, and then generating a voltage of EAB when heated. Jikwang, Jonsung, and Younghwa (2009) emphasize that the produced voltage is proportional to the difference between the measured joint temperatures and the reference point, which is determined experimentally and it depends on the type of materials that are used. A temperature monitoring system when using a thermocouple includes connectors, thermocouple, isothermal block, extension wires, and a transmitter also known as a voltmeter.  This schematic (figure 6) is for type J iron (Fe) Constantin Cu-Ni thermocouple. Nieuwenhove and Vermeeren (2004) describe that when the thermocouple junction is cooled or heated, a digital voltmeter or potentiometer can be used to measure the resulting voltage.   

Biology Essay Example | Topics and Well Written Essays - 500 words - 17

Biology - Essay Example There were no fossils available at this time to make comparisons or linkages. As a result what was available was visual and the comparison was made to gorillas and chimpanzees which included bonobos. Authors and researchers A. C. Wilson and V. M. Sarich wrote that quantitative comparisons made of serum albumins, transferrins, hemoglobins, and DNA show that man is more similar to African Apes than to old world monkeys. They argued that the inference made by some regarding monkeys to men is not correct. (Wilson, Sarich 1088) This argument is made well simply because the original argument made by Darwin as Dawkins points out was in favor of Apes and chimpanzees versus monkeys. Additional support for the theories originally postulated by Darwin abounds as a result of the use of DNA. Dawkins address’s the various fossils and skeletons found, Ape Man, Java man, Peking man and more and debunk the creationist approach in this regard. He does make it clear that he respects the creationists approach regarding the use of arguments that are not valid, though his disdain for them shines through in the surrounding texts. Though the argument against the missing links has valid points, the author Dr. Marvin Lubenow makes it clear that the fossil presentations can be called into question simply because they cannot be definitively shown to be human or of human ancestry. (Lubenow 10-17) Dawkins continues to place what is known and accepted ahead of these arguments however, and shows that some of the more lurid attempts to challenge the fossil records are not based in science but in popular belief. As we read through the next two chapters we are quickly made to see that some of the more normal arguments made against evolution truly are baseless. One argument for which Dawkins quotes a brilliant response is the argument that man could come from a single cell. The response is swift