LINGUIST List 2.833

Wed 04 Dec 1991

Disc: Code-Switching, Helium, Mac Tree-processing, Lojban

Editor for this issue: <>

Directory

1. , code-switching in French
2. Osamu Fujimura, Re: 2.827 Responses: Macs, Tag Questions, Communicative Strategies,
3. Michel Eytan LILoL, Re: Tree-processing on Macs
4. Jacques Guy, Fantastic linguistics

In an article by Sankoff and Mainville in the Revue quebecoise de linguistique
 (1986), code-switching is referred to a 'alternance de langue'.
Lachlan Mackenzie

Message 2: Re: 2.827 Responses: Macs, Tag Questions, Communicative Strategies,

 Helium
> Date: Mon, 25 Nov 91 18:11:33 -0500
> From: gb661csc.albany.edu (BROADWELL GEORGE AARON)
> Subject: helium explained
>
> Helium is less dense than air, therefore the speed of sound in
> helium is faster. Since faster sound equals higher frequency, helium
> speech is higher than ordinary speech.
>
> (I hope I haven't muddled this recount!)
>
> I considered bringing helium balloons to class to let the students try it,
> but I decided I couldn't get it past the human subjects board. :-)
>
> Aaron Broadwell
I think the explanation above reflects a common misunderstanding.
>From a theoretical point of view, the sound propagation speed is determined,
assuming ideal gas, by the gas constant gamma, which is the ratio of
the specific heat constants, one with volume constant and the other pressure
constant. This constant is in turn determined by the degree of freedom
for describing the state of each molecule, and is a function of the number
of atoms that compose the gas molecule. Helium thus has a higher speed
of sound propagation basically because it is monoatomic, unlike most gas
molecules in the air. There are further details that affect the actual
speed. The empirical values for different gases can be found in the
handbook issued by the Institute of Physics, for example.
There is another effect that affects the formant frequencies, particularly
the lowest, as well as formant bandwidth: the acoustic impedance of the vocal
tract walls has different effects on the acoustic characteristics of the
vocal tract acoustic system depending on the density of the gas contained.
The lighter the gas, the more reflective the walls, acoustically. The effect
of the air density on the first formant frequency, particularly for high
vowels, is quite significant. For example, when the acoustic tube is
completely closed by, say, the bilabial closure, the first formant should be
zero Hz if the walls were infinitely heavy (relative to the gas). The empirical
value of the first formant frequency for bilabial closure, with the glottis
closed, is about 170Hz to 200Hz for male subjects according to our sweeptone
measurements, and higher for female subjects. This discrepancey is due to
the finite density ratio between the flesh (basically water) and gas.
References:
G. Fant and B. Sonesson, Speech at high ambient airpressures, QPSR No. 2,
Royal Inst. Tech. pp. 9-21 (1964)
O. Fujimura and J. Lindqvist, Sweep-tone measurements of vocal-tract
characteristics, J. Acoust. Soc. Am. 49, 541-558 (1971).
Osamu Fujimura
osamushs.ohio-state.edu

a few days ago smeone asked about a Mac program for tree-processing (sorry, I
 lost the message so I cannot reply directly to the sender).
There is a very old program that seems to do just what was asked for:
'Hands On' by John Glenn, Dartmouth Aug. '84
It seems very little known and I am not sure it is still sold. Anyway, it is a
 very nice product and near perfection as far as the programming is concerned,
 since it _still works_, on a Mac II si with system 6.0.7! (I must admit that I
 do not use system 7.0 because I do not feel like chucking out 50% of my INITs
 and trying to acquire new versions of the other 50%).
Although not doing exactly what Hands On does, there is another old program for
 tree-processing that might interest some people:
'Think'n Time' from Mainstay '87
it comes with some text-processing abilities but no parsing, contrary to Hands
 On. I can give the exact references to people who are interested (an address in
 the U.S. and one in Belgium); I guess there must be new versions around.
#Michel Eytan #Tel:+33 88 41 74 29	 #

...perhaps a continuation of the "language in movies" thread.
During my electronic peregrinations I have discovered this
artificial language called "guaspi", which seems to me a
send-up of Lojban and Loglan. For those interested in the
unusual, here is how to get it. Send this message:
send guaspi brochure
to this address:
langservhebrew.cc.columbia.edu