时间：2011-03-11 23:13来源：蓝天飞行翻译 作者：admin 点击：次
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Mock-ups can also be a portion of a complete device used as a training aid. In this regard, the control system and instruments of an aircraft or spacecraft can be made into a mock-up, so flight crews can be trained before the actual vehicle is ready for flight. mode C intruder alert (air traffic control). A function of certain air traffic control automatic systems designed to alert radar controllers to existing or pending situations between a tracked target (known IFR or VFR aircraft) and an untracked target (unknown IFR or VFR aircraft) that requires immediate attention or action. modem. A MOdulator-DEModulator used to connect two computers by way of telephone lines. Digital information from one computer is changed into tones for transmission over the phone lines. This is the function of the modulator. At the receiver end, the tones are changed back into digital information for the other computer to process. This is called demodulation. modification. An alteration or change made to the basic design of a product or component. If the basic design of an airplane calls for the installation of a particular engine, the change of the design so another engine can be installed is a modification of the original design. modify. To change something. If a schedule requiring something to be done every six days is changed to require it to be done every ten days, the schedule has been modified. modular engine construction (gas turbine engines). The method of construction used on most modern gas turbine engines. The engine is made up of several modules, or units, that can be removed and replaced or serviced independent of the rest of the engine. modular maintenance. A form of maintenance used on many types of complex machinery and equipment. Modular equipment is made in units (modules) that can be removed and replaced with another module in a minimum of time and with a minimum of equipment. The malfunctioning module can then be taken to a facility in which specialists using sophisticated equipment can isolate the problem and fix it. Modern turbine engines and most sophisticated electronic equipment are made to allow for modular maintenance. modular structure. A structure built in standard units, or modules. modulate (radio communications). In radio communications, to modulate means to change some characteristic, such as amplitude, frequency, or phase of an alternating current wave. A radio-frequency (RF) wave having a constant amplitude can be amplitude modulated (AM) by an audio-frequency (AF) voltage changing the amplitude of the RF wave in the same way the amplitude of the AF signal varies. The changes in voltage of the modulated RF wave can be used to produce a varying AF voltage. This process is called demodulation. modulated light. Light whose intensity is changed by an audio-frequency AC voltage. When modulated light shines on a photoelectric cell, the output of the cell changes in the same way as the intensity of the modulated light. |
