Air Data Computer

Altitude information is determined within an Air Data Computer (ADC) using the principles of the mechanical altimeter, with the resultant altitude transmitted to the DCU on an ARINC 429 data bus (see Section 3.5). The ADC is connected to the pitot-static system, with both the No. 1 ADC and Standby Instrument being fed by the port side system and the No. 2 ADC being connected to the starboard system. Each ADC is also connected to the onside Total Air Temperature (TAT) probe. 

Each DCU is continuously supplied with altitude data from both Air Data Computers (ADCs) and will compare the readings to alert the flight crew if there is a loss of one data source or a large discrepancy between readings. 

Glover DE, Hall RG, Coston AW, Trilling RJ. Validation of data obtained during exposure of human volunteers to air pollutants. Computers Biomed Res 15(3) 240-249, 1982. 

Under the title "Formation of Pressure Wave , Cook (Ref 53, p 324) related the pressure rise in the front of an ait "shock wave to the point at which the initial air shock wave from unconfined charges is obliterated by the emerging gas cloud of the products of detonation. His table 13.3 (our Table 2) presents some selected thermodynamic data computed by R. Becker for air shocks relating, among other quan-... 

FIG. 2-5 Pressure-enthalpy diagram for dry air. Properties computed with the NIST REFPROP Database, Version 7.0 (Lemmon, E. W., McLinden, M. O., and Huber, M. L., 2002, NIST Standard Reference Database 23, NIST Reference Fluid Thermodynamic and Transport Properties—REFPROP, Version 7.0, Standard Reference Data Program, National Institute of Standards and Technology), based on the equation of state of Lemmon, E. W., Jacobsen, R. T., Penoncello, S. G., and Friend, D. G., Thermodynamic Properties of Air and Mixtures of Nitrogen, Argon, and Oxygen from 60 to 2000 K at Pressures to 2000 MPa, /, Phys. Chem. Ref. Data 29 331-385, 2000. 

Units of Measure Units of measure for dilution ventilation are volmne units of air flow. One measure is cubic feet per minute. Air changes per hour are not a good measure, because those reflect room volume only. This does not reflect the rate of contamination reduction. Dilution ventilation requirements are the amount of clean air required relative to the amount and rate of contaminant generated. Computation of ventilation required should adjust air data to standard temperatore (0 °C) and pressure (460 mm Hg). The volume of air varies somewhat with atmospheric conditions. 

GNC Navigation Responsible for estimating the current state of the vehicle based on measures provided by sensors and actuators. It also computes derived air data and aerodynamics parameters required by Guidance and Control. 

Seeing the success of the UNAMAP BBS, EPA s Office of Air Quality Planning and Standards started a BBS for information on regulatory models in June 1989. This has expanded to a BBS called TTN, Technology Transfer Network. This BBS, in Durham, NC, is reached on (919) 541-5742 and the system operator on (919) 541-5384. A part of this BBS called SCRAM, Support Center for Regulatory Air Models, contains model FORTRAN codes, model executable codes for use on personal computers, meteorological data, and in some cases model user s guides. Much of the information is downloaded in "packed" form, and software to unpack the files must also be downloaded from the bulletin board. 

Classes II and III include all tests in which the specified gas and/or the specified operating conditions cannot be met. Class II and Class III basically differ only in method of analysis of data and computation of results. The Class II test may use perfect gas laws in the calculation, while Class III must use the more complex real gas equations. An example of a Class II test might be a suction throttled air compressor. An example of a Class III test might be a CO2 loop test of a hydrocarbon compressor. Table 10-4 shows code allowable departure from specified design parameters for Class II and Class III tests. 

Atmospheric emissions of sulphur dioxide are either measured or estimated at their source and are thus calculated on a provincial or state basis for both Canada and the United States (Figure 2). While much research and debate continues, computer-based simulation models can use this emission information to provide reasonable estimates of how sulphur dioxide and sulphate (the final oxidized form of sulphur dioxide) are transported, transformed, and deposited via atmospheric air masses to selected regions. Such "source-receptor" models are of varying complexity but all are evaluated on their ability to reproduce the measured pattern of sulphate deposition over a network of acid rain monitoring stations across United States and Canada. In a joint effort of the U.S. Environmental Protection Agency and the Canadian Atmospheric Environment Service, eleven linear-chemistry atmospheric models of sulphur deposition were evaluated using data from 1980. It was found that on an annual basis, all but three models were able to simulate the observed deposition patterns within the uncertainty limits of the observations (22). 

TEMPERATURE CONTROL, WB WATER, OB OIL BATH, HAB>HOT AIR BATH, E ELECTRIC CUVETTE, P-PLASTIC, D DISPOSABLE, FT FLOW THROUGH DISPLAY, D DIGITAL, A ANALOG COMPUTER AND DATA REDUCTION, +=YES... 

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