Load, average factor

Traffic analysis consists of estimating the axle load distribution spectrum (single, tandem, tridem and squad axle loadings) applied to the pavement structure. These data are obtained from WIM studies default values for axle load distribution are also available in case limited WIM data are available. The MEPDG does not use ESAL and hence does not require load equivalency factors. The MEPDG procedure, apart from average annual daily truck traffic, lane distribution, truck growth factor and axle load distribution, also utilises some new input data. These are the operational speed, the monthly and hourly distribution of traffic and the lateral wander of axle loads. 

Figure 6.66 Average load factor Ki. when started against load...

Ki = mean load factor, i.e. the ratio of the average load torque to the motor torque which depends upon the loading on the motor during start-up. 

Emission factors must be also critically examined to determine the tests from which they were obtained. For example, carbon monoxide from an automobile will vary with the load, engine speed, displacement, ambient temperature, coolant temperature, ignition timing, carburetor adjustment, engine condition, etc. However, in order to evaluate the overall emission of carbon monoxide to an area, we must settle on an average value that we can multiply by the number of cars, or kilometers driven per year, to determine the total carbon monoxide released to the area. 

Load factor The ratio of the average demand to the maximum demand may relate to electrical, heating, or cooling load. 

Diesel engines, however, operate on an unrestricted air flow at all speeds and loads to provide the cylinders with an excess air charge. This results in a very lean air/fuel ratio of approximately 90 1 to 100 1 or higher at an idle speed. At the engine s rated speed (full load maximum power output) the air/fucl ratio will drop to 20 1 to 25 1 but still provide an excess air factor here of 10 to 20 percent. This excess air supply lowers the average specific heat of the cylinder gases, which in turn increases the indicated work obtained... 

Liquid height, ft = Non-condensable load factor = Latent heat of vaporization of steam, BTU/lb = Average mol weight of system vapors = Molecular weight of non-condensable gas = Molecular weight of condensable vapor = Total absolute pressure, Ibs/sq in. absolute (or other consistent units), or system operating pressure, torr... 

Power-Factor Correction. The induction motors used for oil-well pumping have high starting torques with relatively low power factors. Also, the average load on these motors is fairly low. Therefore, it is advisable to consider the installation of capacitors to avoid paying the penalty imposed by most power companies for low-power factor. They will be installed at the individual motors and switched with them, if voltage drop in the distribution system is to be corrected as well as power factor. Otherwise they may be installed in large banks at the distribution center, if it is more economical to do so. 

Power factor adjustment Although related to the average power factor of the load, the method of calculation may be based directly on measured power factor or on the measurement of reactive kVA over the period. Values at which power factor charges are incurred vary from 0.8 to 0.95 lag. 

With a supply system pressure of 1 kPa and another 250 Pa for the return air duct, the total fan energy of a central all-air system may amount to 12.5% of the maximum installed cooling load, and a much greater proportion of the average operating load. This power loss can only be reduced by careful attention to design factors. 

The connection of AA-size cells in parallel can replace larger cells (e.g., D-size cells). Four AA cells fit into a D-size can, and six AA-cells are in equivalent weight to a D-cell [27]. The utilization of the Mn02 cathode is considerably improved because the cathode thickness is only 2 mm in a AA cell, but 5 mm in a D-cell. The internal resistance is also lower by a factor of 4 to 6. Figure 11 depicts a 5 PxlO S bundle battery five AA cells in parallel = 1 bundle, 10 bundles in series make a (nominal) 12 V battery. It is used as the power source for a transmitter/receiver service. A typical load profile is 2 A for 1 min, 0.33 A for 9 min average load, 0.5 A per bundle or 0.1 A per cell service, about 15 h. Smaller bundle batteries (with 2x9 cells) are very suitable for notebook-computers 18 AA cells weight 0.36 kg, and the total initial capacity is 32 Wh. 

Fig. 9-8 Histogram of dissolved solids of samples from the Orinoco and Amazon River basins and corresponding denudation rates for morpho-tectonic regions in the humid tropics of South America (Stal-lard, 1985). The approximate denudation scale is calculated as the product of dissolved solids concentrations, mean armual runoff (1 m/yr), and a correction factor to account for large ratios of suspended load in rivers that drain mountain belts and for the greater than average annual precipitation in the lowlands close to the equator. The correction factor was treated as a linear function of dissolved solids and ranged from 2 for the most dilute rivers (dissolved solids less than lOmg/L) to 4 for the most concentrated rivers (dissolved solids more than 1000 mg/L). Bedrock density is assumed to be 2.65 g/cm. (Reproduced with permission from R. F. Stallard (1988). Weathering and erosion in the humid tropics. In A. Lerman and M. Meybeck, Physical and Chemical Weathering in Geochemical Cycles," pp. 225-246, Kluwer Academic Publishers, Dordrecht, The Netherlands.)...

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