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Posted: Sun 21:05, 12 Dec 2010 Post subject: ugg boots billig Measuring interference in the mea | |
Measuring the interference A new method of measuring humidity
Saturated water vapor pressure (), so you can under the (4, calculated the water vapor pressure} However, the recommended saturated vapor pressure table is not easy to directly use a computer,ugg boots billig, and a larger temperature interval of the table in order to facilitate the computer automatically measured. Also need to the saturated vapor pressure table \pressure values extracted into the second row of Table 1 (extract). From the data extracted can be seen in (20 soil 0.5) ℃ range,tory burch, air temperature and saturated water vapor pressure value is linear because in the laboratory conditions, the air temperature control in (20 soil 0.5). C,tory burch shoes, in (20 soil 0.5) ℃ within the line of the table data to be received = 145.32t an 567.85 station (5) by (5) at different temperatures in n fill the third row in Table 1 (calculation), you can see in (20 soil 0.5) ℃ range, with (5), the calculated saturated vapor in the air pressure compared with the standard value, the maximum uncertainty 1Pa. using formula (5) calculation of 19.0. C, and 21.0. C the saturated vapor pressure (see Table 1), the largest uncertainty 4Pa. means that although (5) in (20 soil 0.5). C} derived range but with at (20 ± 1.0). C range of domestic,ugg stivali, the formula itself, the bow into the error of f is still not great. With (5) to the work of eliminating the examination table, the computer automatically calculate and create the conditions for the acquisition. by (3) and (4) export U/100 × (145.32t a 567.86) (6) where, u - relative humidity,% RH; e - air, water vapor pressure, Pa} f - air temperature,. C. as long as the measurement of the environmental air temperature and relative humidity, you can use (6) calculate the water vapor pressure. On the surface, this method need to increase the air temperature measurement device f in fact, ptf calculation method itself need to measure atmospheric pressure and air temperature, air temperature has been package measuring equipment units so I do not need an additional air temperature measuring instruments. and the number of his temperature sensor is very common, so use of Ij (6) calculated water vapor pressure equipment is relatively simple. We use the Finnish company's HMP35A VAISALA type relative humidity sensor. The output is analog, the A / D converter circuit into a digital, transmission to the computer and digital display table, after calibration, environmental conditions at 20 ℃, its measurement uncertainty (including nonlinearity and hysteresis) of 2% RH [. air temperature with a thermistor temperature sensor, the temperature measurement uncertainty is 0.01. C. 2 Relative humidity measurement accuracy of 2% RH 『uncertainty into the measurement uncertainty = 2 / 100 ~ 2411 = 48.2Pa air temperature measurement uncertainty introduced by 0.01 ℃ Uncertainty. = 60/100 × 145.32 × 0.01 = 0.87Pa air saturated water vapor pressure in the calculation of the introduction of linear uncertain degrees in air temperature (2O soil 0.5) range,ugg boots günstig, a = 1Pa in air temperature (2O soil 1.0) ℃ range,. 4Pa combined standard uncertainty (2O soil 0.5) ℃ range = (chu) = (48.2 +0.87 +10) = 48.22Pa (20 soil 1..). C range \48.37Pa can be seen from the above analysis, the air temperature in a certain range. by measuring the relative humidity and air temperature to calculate the water vapor pressure, and its precision depends on the relative humidity measurement accuracy. Also, because the relative humidity sensor accuracy depends mainly on to its non-linear, if the thorns with a relative humidity of the laboratory of the characteristics of small range. considerable humidity in the humidity and the actual range of relative humidity sensor calibration can be improved so that the relative humidity sensor measurement uncertainty, so that the water vapor pressure measurement accuracy is significantly improved. 3 experiments with conventional electric ventilated psychrometer and we use the HMP35A-type relative humidity sensor, humidity conditions in the laboratory to do the actual comparison experiments. The experimental results shown in Table 2 by Table 2 shows that both methods measure the water vapor pressure difference between the measured values of relative humidity sensor is much smaller than the uncertainty of measurement. 4 Results Cambodian language means that measurements of water vapor pressure has been applied to 500ITffI1 laser interference than the length gauge, Coriolis, and two-meter grating interferometer column line pattern development of the instrument set subject, through the use to prove its accuracy to meet the measure to (continued on page 41) 相关的主题文章: tory burch sale Beijing Great Wall Institute for M tory burch GC detector performance indicators disc ugg milano Second-class standard mercury thermomet |