Ice conditions

The other area of ecological diagnostic interests is the water, water basins and ice condition monitoring. 

Another problem, prevalent ia areas where severe icing conditions are met, is referred to as galloping of power lines. When ice forms on a power line, there is frequently a prevailing wiad which causes the ice to take a teardrop or airfoil shape. This foil provides an aerodynamic lift to the conductors and under certain conditions the conductors can go iato a resonant vibration such that large standing waves are created that exert enormous forces on the system. Miles of power lines and the towers along them have been destroyed by this phenomenon. 

Highway. Rock salt, solar salt, and in some cases in Europe, evaporated salt are used to maintain traffic safety and mobiUty during snow and ice conditions in snowbelt regions throughout the world. Sodium chloride melts ice at temperatures down to its eutectic point of —21.12°C. Most snowstorms occur when the temperature is near 0°C, where salt is very effective. More than 40% of dry salt produced in the United States is used for highway deicing. 

Sers ice conditions As for other equipment (e.g. motors, transformers or swdtchgears) a surge arrester is influenced too by unfavourable operating conditiotis such as noted in Table 18.4. 

The bearings must be adequate to handle the shaft loads without excessive wear, provided lubrication is maintained. Usually this is not a point of real question provided the manufacturer has had experience in the type of loads imposed by the ser ice conditions, and the responsibility for adequate design must be his. 

Individual fill assemblies shall be designed to be removable. Fill shall be properly supported and fastened to prevent warping or buckling under all expected operating or icing conditions. 

The successful solution of some of these problems can be exemplified by the 3-D model that calculates the dynamics of radionuclide pollution of the Arctic Basin (Preller and Cheng, 1999) and the 2-D model of the ice condition of Arctic Ocean basins (Riedlinger and Preller, 1991). 

Plotnikov V.V. (1996).Long-term prognosis of Okhotsk Sea ice conditions by considering large-scale atmospheric processes. Meteorology and Hydrology (Moscow), 12, 93-100 [in Russian],... 

Since test conditions w ill seldom match the valve s serv ice conditions, the actual leakage in service may be significantly different from that specified in the standard. This may be due to temperature, fluid type, in-sen ice wear, differential pressure, or seat load. Each of these is discussed below. 

Jevrejeva, S., Moore, J. C., 2001. Singular spectnim analysis of Baltic Sea ice conditions and large-scale atmospheric patters since 1708. Geophysical Research Letter, 28, 4.503 4.506. 

A synoptic characterization of the entire area of the Baltic Sea is hardly possible because conditions vary considerably at the local level. Therefore, separate descriptions of meteorological and hydrographic conditions will be given for the individual areas. The typical ice conditions will be described with respect to each area. The mean and extreme values of some important ice parameters (beginning and end of the ice season, number of days with ice, duration of the ice season and thickness of level ice if known) for selected stations can be found in Table 8.2. Relative frequency of ice occurrence in the B altic Seals shown in Fig. 8.4. 

Ice conditions on the Polish coast differ depending on the hydrographic nature of the coasts. Ice forms. .. 

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