Mines defined

In summary, it can be seen, the Aging Mine defined standard feature selection, mainly reflected in the following indicators recoverable reserves length of service economic benefits efficiency production capacity. 

The area of machine learning is thus quite broad, and different people have different notions about the domain of machine learning and what kind of techniques belong to this field. We will meet a similar problem of defining an area and the techniques involved in the field of "data mining , as discussed in Section 9.8. We will use the term "machine learning in this chapter to collect aU the methods that involve learning from data. 

Handling of complex data sets Visual data mining methods especially show huge advantages over classical approaches if only Httle information about the data is known or if the expected patterns and relationships are not clearly defined. Furthermore, very inhomogeneous data sets or data with a high noise level can still be analyzed by these methods. 

A variety of methods have been developed by mathematicians and computer scientists to address this task, which has become known as data mining (see Chapter 9, Section 9.8). Fayyad defined and described the term data mining as the nontrivial extraction of impHcit, previously unknown and potentially useful information from data, or the search for relationships and global patterns that exist in databases [16]. In order to extract information from huge quantities of data and to gain knowledge from this information, the analysis and exploration have to be performed by automatic or semi-automatic methods. Methods applicable for data analysis are presented in Chapter 9. 

Fluid deposits are defined as those which can be recovered in fluid form by pumping, in solution, or as particles in a slurry. Petroleum products and Frasch process sulfur are special cases. At this time no vaUd distinction is made between resources on the continental shelf and in the deep oceans. However, deep seabed deposits of minerals which can be separated by differential solution are expected to be amenable to fluid mining methods in either environment. 

The mean residence time T (defined as H JF) is the most important parameter, since it determines the time over which particles are exposed to grinding. Measurements on several industrial mills (Weller, Automation in Mining Mineral and Metal Processing, 3d IFAC Symposium, 303-309, 1980) (measured on the water, not the ore) showed that the maximum mill filhng was about 40 percent, and the maximum flow velocity through the mill is 40 m/h. 

Among common areas where explosion can occur are coal mines, petrochemical plants, chemical plants, paint shops, grain handling industry, etc. Explosive limits for gases and vapors are expressed as percentages (% ), and may be defined as minimum and maximum concentrations of a flammable gas or vapor between which ignition occur. Concentrations below the lower explosive limit (LEL) are too lean to burn, while those above the upper explosive limit (UEL) are too rich. Table 7.8 lists explosive limits for some common gases. 

For each unit process, a reference flow may be defined, and the inputs and outputs to the unit process calculated in relation to the reference flow. For instance, the reference flow for mining of iron ore is the mass of iron ore mined per year, and the emissions to the air may be expressed as kg dust per metric ton of ore. 

In 1976 the USGS/U.S. Bureau of Mines (USBM) defined resources and reserves (Figure 1) as follows. 

Of these neutron interactions, those that produce prompt-7 rays were evaluated as the most feasible for mine detection. As discussed in the Introduction, we define a prompt 7-ray as one which is produced as a direct result of the primary neutron interaction, usually within nanoseconds of that initial event. Such reactions are obviously attractive because they can best satisfy the desired rapid sweep rate over a minefield. The three specific neutron-prompt gamma reactions that were intensively investigated by the US Army are listed below ... 

The ratio of total water use to water availability under water stress can be defined as Water scarcity (in % = total water use/water availability). It will generally range between 0 and 100%, but can in exceptional cases (e.g. groundwater mining) be above a 100%. For example, this ratio is in Algeria 39.8%, in Egypt 105.8%, in Jordan 114.5%, in Lebanon 33.4%, in Morocco 42.2%, in Syria 75.3%, and in Tunisia 56.6 [6]. 

The propagation of premixed flames in closed vessels has been a subject of combustion research since its inception as a defined field of study in the late 1800s, when Mallard and LeChatelier [1] explored the behavior of explosions in the tunnels of coal mines. In the early decades of the twentieth century, experimenters used streak cameras to monitor the progress of premixed flame fronts propagating in tubes and channels without... 

The Y, C and B sub-types roughly correspond to types 1, 2 and 3 as defined by Urabe (1974a), who classified Kuroko deposits based on hydrothermal alteration and ore mineral assemblages type 1, kaolinite-pyrophyllite-diaspore-type type 2, sericite-chlorite-type type 3, sericite—chlorite-carbonate-type. Hydrothermal alterations in the Kuroko mine area are described in section 1.3.2. 

Fig. 2.55. Nickel contents of pyrite from the deposits of the Fujimi and Fudotaki groups of the Hitachi mine. Symbols as defined in Fig. 2.54 (Kase and Yamamoto, 1985).

More than 90% of the world s nickel is obtained from pentlandite ((FeNi)9S8), a nickel-sulfitic mineral, mined underground in Canada and the former Soviet Union (Sevin 1980 IARC 1976 WHO 1991). One of the largest sulfitic nickel deposits is in Sudbury, Ontario (USPHS 1993). Nickeliferous sulfide deposits are also found in Manitoba, South Africa, the former Soviet Union, Finland, western Australia, and Minnesota (Norseth and Piscator 1979 USPHS 1993). Most of the rest of the nickel obtained is from nickel minerals such as laterite, a nickel oxide ore mined by open pit techniques in Australia, Cuba, Indonesia, New Caledonia, and the former Soviet Union (Sevin 1980). Lateritic ores are less well defined than sulfitic ores, although the nickel content (1 to 3%) of both ores is similar (USPHS 1993). Important deposits of laterite are located in New Caledonia, Indonesia, Guatemala, the Dominican Republic, the Philippines, Brazil, and especially Cuba, which holds 35% of the known reserves (USPHS 1993). Nickel-rich nodules are found on the ocean floor, and nickel is also present in fossil fuels (Sevin 1980). 

Figure 6-5 Maximum pressure for methane combustion in a 20-L sphere. The flammability limits are defined at 1 psig maximum pressure. Data from C. V. Mashuga and D. A. Crowl, Process Safety Progress (1998), 17(3) 176-183 and J. M. Kuchta, Investigation of Fire and Explosion Accidents in the Chemical, Mining, and Fuel-Related Industries A Manual, US Bureau of Mines Report 680 (Washington, DC US Bureau of Mines, 1985).

This task was assigned to what is now called the Safety in Mines Research Establishment. It was at this organization where the concept of intrinsically safe electrical circuits was first defined after continued research into the ignition of methane-air mixtures. 

For As, Mo, and Se all samples displayed well-defined absorption edges, identified by the sharp increase in absorption over a 10 eV interval. The position of the absorption edge is sensitive to the oxidation state of the absorbing atom and thus has been used to determine the oxidation state of As, Mo, and Se in the mine tailings. 

Sour natural gas, 23 597 Sour syngas defined, 6 829 Sour taste, 11 566 South Africa, platinum-group metal deposits in, 19 604, 612 South African gold mines, 12 686 South African manganese mining, 15 555 South America... 

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