Role of Operating System

David Klein

Description

• mémoire
• mémoire - matière potentielle : architecture divides memory into segments
• mémoire - matière potentielle : multiprocessor
• mémoire - matière potentielle : model
• expression écrite
• mémoire - matière potentielle : access system
• mémoire - matière potentielle : references

Nov-20-03 CSE 542: Operating Systems 1 Role of Operating System • Operating systems are designed to provide uniform abstraction across multiple applications: fair sharing of resources • General purpose OS like Solaris in wizard.cse.nd.edu – Mail, web, samba server, telnet, emacs … – Memory fs, afs, ufs … – Fibre channel devices, floppy disks … • What about applications/services such as video games, data base servers, mail servers – OS gets in the way of these applications in the name of fairness (MSDOS is the ideal OS!!)

• uniform abstraction across multiple applications
• multiple man-machine interaction to the sequential processing of absentee-user jobs
• programs access files
• hardware from a virtual address to a real address
• computer industry
• multics
• memory
• system

Sujets

• Mémoire
• Multiprocessing
• Reference
• Brian Kernighan
• Honeywell

Informations

• Publié par: kepap
• Nombre de lectures: 84
• Langue: English
• Poids de l'ouvrage: 1 Mo

Extrait

The Physics of Music  Physics 15 University of California, Irvine

Lecture 13 § Woodwinds: air reeds § Brass Instruments

Instructor: David Kirkby (dkirkby @uci.edu)

Air Reed Examples of air reed instruments include the flute, recorder, and whistles.

In an air reed instrument, a thin jet of air plays the role of the cane reed(s) of other woodwind instruments.

The air reed has two main components:  Air jet  Sharp edge

Physics of Music, Lecture 13, D. Kirkby

Air Jets and Edges An air jet striking a sharp edge will be deflected to one side of the edge.

If the jet is centered on the edge, turbulence can cause it to switch back and forth between sides in a chaotic way.

The coupling of an air jet with an edge produces sound of its own, which we describe as wind whistling or aeolian tones. These tones are inharmonic and noisy.

Physics of Music, Lecture 13, D. Kirkby

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Instructor: David Kirkby [e-mail]

Miscellaneous I will be traveling on Nov 26 (Tuesday before Thanksgiving). There will be a guest lecture, Prof. David Casper.

Problem Set #7 (the last one) will be handed out next Thursday (Nov 21) but not due for two weeks.

No office hours 1011am on Wednesday Nov 27 (afternoon hours are still OK).

Physics of Music, Lecture 13, D. Kirkby

Air Jets and Turbulence As fast air is forced out through your lips, it comes in contact with the stationary surrounding air. This contact triggers turbulent eddies to form, which in turn disturb the flow pattern.

Physics of Music, Lecture 13, D. Kirkby

When an air jet and edge are coupled to a resonator (such as an air column), the frequency selectivity of the resonator can harness the chaotic jetedge vibrations to store energy at harmonic frequencies.

The jetedge (air reed) vibrations are reinforced and synched to the air columns vibrations by a feedback mechanism (similar to the other reed instruments).

In this case, the feedback relies on the direction of air flow in the standing wave rather than pressure pulses.

Physics of Music, Lecture 13, D. Kirkby

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