You should get more exercise. (The speaker thinks this is a positive or even necessary course of action.) You might find work on a farm. (The speaker thinks there is a weak possibility of finding work.) B. share certain grammatical features that make them grammatically, but not semantically, interchangeable 12 Formal Modals and general semantic areas (not exhaustive)
semantic area: potere
|
semantic area: dovere
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semantic area: futurity/conditionality/dovere
| |
can
|
must
|
will
|
need
|
could
|
should
|
would
|
dare
|
may
|
ought to
|
shall
| |
might
| | | | Potere as:
can
|
be able to
|
must
|
have to
|
could
| |
should
|
had better
|
may
|
be allowed to
|
ought to
|
be supposed to
|
might
| | | |
Semi-modal forms:
ability, capacity
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present
|
can
be able to
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I can speak French.
This glass can hold 400 centilitres of liquid.
| |
past
|
could
was able to
|
I could swim when I was 10.
He was able to swim to shore when the boat sank.
|
permission
|
present
|
may
is allowed to
can
|
You may not park here.
cannot
are not allowed to
| |
past
|
was allowed to
|
When I was a child, girls were not allowed to wear trousers to school.
| Potere as possibility/probability:
present/
future
|
may
|
He may be at home.
could
might
| |
could
| | |
might
| |
past
|
may have
|
They may have told Sue.
could
might
| |
could have
| | |
might have
| | Potere as possibility/probability:
Possibility/probability is an opinion
is will may could/might
factual certain prediction possible less possible
Jack is studying. (I know it for a fact.)
He will study all afternoon. (I feel very certain in predicting this.)
He may study all afternoon. (He has a test tomorrow.)
He could/might study all afternoon. (He has a test tomorrow but he is already well prepared.)
Multimedia hardware: - Multimedia Hardware
- Platforms and Processors – aspects of personal computer that affect the development and delivery of multimedia applications.Input Devices – there are a wide variety of ways of interacting with multimedia applications.Multimedia Storage – the high storage demands of multimedia materials require careful estimation and consideration of storage media.Multimedia Connections – speed of presentation will depend on the appropriate connection between devices.
- 3 Platforms and Processors The multimedia platform – the equipment on which multimedia is developed or played – needs a very comprehensive description because it covers not only the processor and operating system but also screen resolution, bit depth and sound, amount of memory and the size of the hard disk storage.It is important to distinguished between development and delivery platforms. Although these can be the same it is quite common for the multimedia application to the developed on one platform (which may have a better performance and features to support the development) and delivered on lower specification machine at a correspondingly lower cost.
- 4 Platforms and Processors Transferring multimedia assets from one platform to another must be done with care as there can be small but significant differences between how the media elements are dealt with (e.g. slightly different sampling rates for sound).
- 5 Platforms and Processors The platform should be precisely defined in terms of the version of operating system, what multimedia facilities are supported, its interaction devices (such as mouse or touch screen) and ancillary devices such as CD-ROM.Other details include:Type and speed of processorSize of hard disk storageSpeed of CD-ROM sizeConnection to networks, both local areas as well as wide area and InternetScreen resolutionNumber of colors supportedSound card features (8-bit, 16-bit etc.)Video compression facilities (AVG, MPEG etc.)
- 6 Platforms OptionsIdeally every multimedia application would run on every platform, but just as in other computer applications this is often not possible.(There are some authoring systems which will generate software for more than one platform).It is of course, possible for one computer platform to emulate another and this will be effective where the ‘host’ platform is based on a fast and powerful processor.A further development of this is the ‘virtual machine’ where a software layer separates the application from the actual machine operating system and the interface between the application and the virtual machine is standard whatever the underlying operating system.
- 7 Platforms OptionsThis approach works best where there is a fairly low level of interactivity as the application software is likely to run more slowly in this arrangement. There may also be problems in the speed of video clips, or number of colors, if the application is not running at optimal performance.UNIX systems have rarely been used for multimedia applications although there may be some potential with on-line systems particularly where UNIX machines run as servers for networks.
- 8 Platforms OptionsVery high quality multimedia can be created on specialized workstations from Silicon Graphics, Sun Microsystems and sometimes mainframe computer, but the two most significant platforms for the production and delivery of multimedia in terms of affordability and availability are:The Windows operating system running on Intel-based IBM PC compatible computersThe Apple Macintosh Operating System
- 9 Platforms OptionsThe IBM PC has been the standard computer platform for business application for many years – there are more than seven IBM compatible PCs for every one Apple Macintosh computer.The same is true of delivery platforms for multimedia applications for business. When installed with Windows a sound card, and Super VGA graphics, the PC rivals the Macintosh in delivering high quality audio and video presentations.
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