Study one economic concept in depth
In managerial economics, managers in depth analyze all the economic situation of the country. After the in depth analysis they take the decisions. In this way economics is integrated with decision making.
Regulatory measures help offset negative impacts; for instance, controls on the number of tourist activities and movement of visitors within protected areas can limit impacts on the ecosystem and help maintain the integrity and vitality of the site. Such limits can also reduce the negative impacts on resources. Limits should be established after an in-depth analysis of the maximum sustainable visitor capacity. This strategy is being used in the Galapagos Islands, where the number of ships allowed to cruise this remote archipelago is limited, and only designated islands can be visited, ensuring visitors have little impact on the sensitive environment and animal habit
The US economy is the largest economy in the world, with one of the highest GDP per Capita. However, despite its position as the most powerful economy, it now faces many serious economic problems. Some of these are short term, but some of them reflect an underlying weakness. National debt and Government Borrowing Due to decades of government borrowing the US national debt is fast approaching $10,000 billion, or more than 65% of GDP. The consequence of such high levels of national debt is to increase the cost of interest payments. It also limits the potential for future tax cuts and higher government spending. High levels of government borrowing can also lead to crowding out. Where government borrowing reduces private sector spending. Current Account deficit and External Debt In the past 2 decades US economic growth has mostly been financed by high levels of consumer spending. This consumer spending has created an increase in imports that has not been met by a corresponding increase in exports. At its peak the US current account deficit reached 7% of GDP. This current account deficit was financed by foreigners buying US securities. It means that most of the US external debt is held by Chinese, Japanese and other investors. A current account deficit has contributed to the declining dollar and remains a constraint on economic growth Housing Market It is estimated US house prices have fallen by 10% in the past 12 months. Although there are many different ways to measure house price statistics, most people will agree that US house prices are falling. There is a combination of oversupply and falling demand due to uncertainty about the future of the housing market. Declining house prices can be a powerful disincentive for consumer spending. As house prices fall, consumers see their wealth decline leading to lower economic growth. It is feared that falling house prices could alone tip the economy into recession. Low savings Ratio The low savings ratio is linked to the current account deficit. It is a result of consumer led growth. It is also a result of increased personal borrowing levels. It is suggested that the economic growth has been based on an unsustainable footing. It means that the American consumer is susceptible to any rise in interest rates. Rise in Commodity prices Despite a slowdown in the US economy, we have seen a rise in cost push inflation. In particular rising prices of oil, wheat and soybeans have created problems for the US economy. It could lead to a situation of stagflation - rising prices and falling growth. Updated: more in depth analysis of the problems facing the US economy. http://ezinearticles.com/?Problems-Facing-American-Economy&id=965725
MINE 290 Introduction to Mining and Mineral Processing Final Examination Time Limit: 3 hours December 5, 2003 MILLING QUESTIONS (76 marks - all questions of equal value) 1. A mill processes 12,500 tonnes of wet ore per day with a relatively low moisture content of 1.5 %H 2 0. The feed grade of dry ore is 2.5 %Pb and 4.8 %Zn. The ore is processed in a differential flotation circuit in which lead is recovered in the first stage to a Pb concentrate at a grade of 67.5 %Pb leaving a Pb circuit tailing containing 0.42 %Pb and 4.75 %Zn. This latter material is fed to a zinc flotation circuit producing a Zn concentrate of 53.6 %Zn and a final tailing containing 0.31 %Zn and 0.26 %Pb. a. What is the percent recovery of Pb to the Pb concentrate and the percent recovery of Zn to the Zn concentrate? b. What is the grade of Pb in the Zn concentrate and the grade of Zn in the Pb concentrate? c. Describe the types of chemicals that would be added to the Pb circuit feed and to the Zn circuit feed and give their function in the flotation circuit. 2. Tailing disposal at a mine site is one of the major expenses involved in both building a mine and then in operating the facility. Problems associated with environmental protection and geotechnical aspects are extremely important if a long-term viable operation is to be achieved. a. Discuss tailing disposal practices with respect to four different methods of disposal. Provide examples of where each method might be used and why its use might be preferred over the other methods? b. What is ARD and why is it such a ubiquitous 1 and important problem in mining? c. Discuss water use in milling with respect to using fresh water and with respect to using recycle water. What aspects of a mill affect the use of recycle water? How can these effects be minimized? 1 Ubiquitous means existing or being everywhere at the same time; constantly encountered; widespread. 2 3. A ore with a work index of 12.5 kWhr/t is ground in a lab ball mill for 10 minutes using a 20,125 gram charge of half-inch stainless steel balls. The 80 % passing size of the ore was initially 4 mm while the 80 % passing size after grinding was 93 microns. A second sample of a similar ore was subjected to the identical procedure. The sample had an 80 % passing size of 3 mm and the product showed an 80 % passing size of 107 microns. a. What is the work index of this second ore sample? b. What is a SAG mill and why has this unit operation become so popular over the past 25 years or so? Is this popularity deserved and what might suggest that SAG milling is overblown as a legitimate process? c. Discuss the differences and similarities between liberation and "grind size". 4. Sustainable Mining is a term used to describe how a mining company and industry designs, operates, manages and closes operations around the world in the 21 st Century. The concept of sustainable mining accounts for technical, economic, environmental, and socio-political aspects of operating a mine in a particular region or jurisdiction. a. From the viewpoint of the principal components of Mining and Milling (Mining, Liberation, Separation, Extraction), discuss how each of these components have changed as the social and political aspects take on a relatively more-important position in the decision-making involved in running a mining company. Give at least one example of how the socio-political aspects of a situation impact on technical decisions in Mining, in Liberation, in Separation and in Extraction. b. Connect each of the terms at the left with its most appropriate match on the right: i. locked particles a. middlings ii. gangue j. copper sulfate iii. hydrophilic g. pH modifier iv. carbon-in-leach i. depression v. head grade e. water-avid vi. riffles b. waste minerals vii. soda ash h. gravity separation vii.jig c. assay of mill feed ix.critcal pH d. gold recovery x.activator f. shaking table c. Why is hydrometallurgical processing becoming a more important extraction process in place of pyrometallurgical processing? Give at least three reasons. 3 MINING QUESTION (25 marks) 5. For the mineral deposit described below, prepare a detailed outline of the steps involved in bringing this prospect (including the major studies required) into a producing mine (5 marks ). Select the mining method which would be best suited, most economical, and safest for the conditions given (5 marks ), defending your choice briefly (5 marks ), and citing the main advantages and disadvantages of the method (5 marks ). Identify the cycle of operations and the major equipment pieces required for supporting your selected mining method (5 marks ). Total 25 marks. Design conditions are as follows: Deposit - a) chalcocite/chalcopyrite ore mineral disseminated in a quartz porphyry intrusive, average grade 0.5% Cu, fairly uniform ore distribution. b) massive irregular deposit, reserves estimated at 100 millions tonnes extending to 350m below ground surface, average depth of covering overburden is 25m. c) ore compressive strength set at 85 MPa, frequent joints. d) host rock is a schist with a compressive strength of 55 MPa, fractured and with distinguishable boundary contact with the ore. Topography - Desert and low mountain ridges, elevation 1370 metres. Climate - Arid, mean annual rainfall 250 mm. Ore Production Rate - 20,000 tpd over a 20-year mine life. Metal Value - $2.00 US/kg.
Both temperature and pressure increase with depth.
In geometry, a point has location but neither height, breadth or depth.
It is an inverse relationship
The depth, purity, and clarity of the individual color.
Depth of field refers to an important aspect used in photography. It describes the distance between the closest and farthest objects in a shot that should be in the camera's focus.
Computed Tomography scan (CT)
It's a 'shorthand' for a document which will be utilized by an individual who will use the notes that it contains to conduct an in-depth presentation (on some subject) to an individual or a group of people.
an aquatic ecosystem's abiotic factor of depth will determine the amount of light received.