Utilisation - Elecrical engineering Assignment Example | Topics and Well Written Essays - 1000 words

Utilisation - Elecrical engineering - Assignment Example In this type of lamp, there is glass tube which is filled with a mixture of mercury vapour at low pressure and argon. The inner side of the tube has a phosphorous coating which is used to illuminate the light. As current flows through the electrodes in the tube, it goes through the gas which is contained between. Consequently, there is emission of ultraviolet light from the mercury arc which is converted to visible light by the fluorescent coating found on the inside of the tube. To facilitate proper lighting in this scenario, a high mercury pressure lamp is necessary to facilitate this lighting system. This is due to the fact that this type of lamp produces less heat and uses less energy and thus it conserves energy while at the same time producing enough lighting. In the design of this type of lamp, an outer glass envelop is filled with nitrogen gas which acts as a coolant that keeps the arc tube at correct temperatures. This type of lamp contains a quartz discharge tube which is filled with argon gas and small amount of mercury which is in liquid form. Two electrodes are located at the ends of the tube which begins the discharge. A 10 – 30 â„ ¦ resistor is connected in series with the secondary electrode. On switching on the light, at first there is no current flow. Then the power supply voltage appears across the main electrode and between one of the mains electrodes and the secondary electrode through the series resistor (B & B training Associates Limited). Consequently, there is production of an arc between the secondary and the main electrode resulting in occurrence of ionisation. The pressure and the heat build-up resulting in the formation of more high pressure and vaporised and high pressure arc between the electrodes. It is made of a sintered aluminium oxide tube that is being supported by two rods. The inside of the glass is coated with white material that facilitates spreading of the light. There is a combination of sodium and

Different types of port ownership and administrative regimes Essay

Different types of port ownership and administrative regimes - Essay Example (CMAISB†¦ 1999, p. 7) These facts underscore the importance of the port ownership in an overall national interest of a state. This paper will outline and explore the various types of port ownership and administrative regimes. Specifically, this will examine four regimes, namely; state, autonomous, private and municipal port administrations. With this objective, a better understanding of various port management structures will be achieved as both the advantages and disadvantages of the four regimes will also be outlined. Company-owned: these ports are subject to the full freedoms and discipline of the commercial marketplace. They are free to seek commercial funding for investment, on commercial terms, borrowing on their assets. They are obliged to account for their performance. They are expected to generate dividends and to increase shareholder value over time. To the extent that they generate retained profits, they have wide discretion over how to invest them. (p. 27) Trust Ports: Trust ports are independent statutory bodies. They have independent boards and trustees charged with acting in the interests of al stakeholders. Any surpluses are ploughed back into improving facilities. (p. 27) Municipal ports: These are ports that are municipally owned. Local authorities operate these facilities for the benefit of the local community, town or city. The function of these ports may be commercial in nature. Company-owned ports can be considered as private ports along with the privatised ones. The main feature that distinguishes these facilities from state or municipal ports regimes is the freedom accorded in their operations. To a certain degree, autonomous ports resemble these private port administrations except that they may differ in the stakeholders involved. For example, autonomous ports may be owned by the government but that they could either be operated commercially or run privately. The port of Holyhead in