Contact, attrition, and structural shift evidence from Oroqen

Contact, attrition, and structural shift evidence from Oroqen
Contact, attrition, and structural shift evidence from Oroqen

Contact,attrition,and structural shift:

evidence from Oroqen

LI FENGXIANG*

Abstract

Oroqen is a Tungusic language spoken in Northeast of China and Inner Mongolia.A considerable amount of data from Oroqen reveal patterns that shed light on our understanding of the complex interplay between language contact and language attrition induced changes.Oroqen has un-dergone drastic restructuring over a relatively short time span of a few decades.I demonstrate that time depth and intensity of contact correlate very closely with the rate and extent of structural borrowing and structural shift that occurred in Oroqen.I argue that the determining factors are soci-olinguistic in nature though some of the changes were initially internally motivated.

1.Introduction

Oroqen is a Tungusic language1spoken by roughly2,500people in two provinces of northeastern China:Heilongjiang Province and Inner Mon-golia Autonomous Region.The ancestors of this remarkably peaceful and harmonious people traversed the treacherous terrain of the Siberian taiga,crossed the mighty Amur and Argun rivers,braved through the formidable almost impenetrable virgin forests of the Hinggan mountains and thrived in their hunter-gatherer lifestyle between the game rich moun-tains and?sh-?lled rivers in Northeastern China and Inner Mongolia deep in the Greater and Lesser Hinggan Mountains.According to Jan-hunen(1997:131),‘‘the ancestors of the Orochen seem to have entered the Chinese side in several waves,mainly during the eighteenth century. The Orochen then gradually spread over the two Khingan Ranges...’’Unfortunately,in recent history they su¤ered the same fate as the other native groups in many parts of the world,such as the American Indians, and the Australian Aborigines.They were ruthlessly trampled by the

0165–2516/05/0173–0055Int’https://www.360docs.net/doc/cd6693907.html,ng.173(2005),pp.55–74 6Walter de Gruyter

56Li F.

army of the Russian Czar in the17th century,and were subjected to the unspeakable atrocities of the Japanese invaders in the1930s,and the Chi-nese warlords in the1940s.Like so many people in China,the Oroqens had their share of tribulations and persecution during the Cultural Revo-lution of1966through1976.Since their settlement in the early1950s, they have been losing their language along with their traditions and cultural heritage at an alarming rate.Sadly,in the very near future,the Oroqen Tungus as a distinctive ethnic group will cease to exist for it will soon be completely engulfed by the invincible superstratum Chinese lan-guage and culture.While their older generation is trying to hold on to their language,culture and traditions,their younger generations are being assimilated into the mainstream Chinese culture at an incredibly fast pace.The Oroqen lived as hunter-gatherers until the early1950s,when the Chinese government began its e¨ort to settle them.Before this time very little was known about the Oroqen language in China outside of piecemeal information provided by the great Russian ethnographer,S. M.Shirokogorov,(Shirokogorov1923[1999],1929±1933,1935,1944). During the early1960s,after the demise of Oroqen nomadism,more comprehensive research on the language began with the pioneering work of Hu Zengyi,resulting in the?rst grammatical sketch of Oroqen(ulti-mately published as Hu1986).One additional grammatical sketch has since appeared(Zhang et al.1989)as well as two phrase books(Han and Meng1993;Saxirong1981),a collection of texts(Meng1993),and work on more speci?c aspects of the grammar(Doerfer1983;B.Li 1992,1996;F.Li1996;S.Li1981;Li and Whaley1998,2000;Whaley and Li1998,2000;Whaley et al.1999;Whaley2001;Zhang1996).It is glaringly obvious among these works that hardly any attention has been devoted to the rapid changes that Oroqen has been undergoing over the last a few decades.Therefore,the aim of this article is to explore both the internal and external factors that led to the drastic changes that have taken place in Oroqen,focusing on the dismantling and reordering of its structural system.Section one of this article is a brief introduction.Sec-tion two is devoted to a discussion of the changes that are attributable to language attrition.Section three deals with contact-induced changes.The ?nal section of the article o¨ers some explanations and systematic pat-terns about contact and attrition situations.

2.Morphological attrition

It has been abundantly demonstrated in the literature that the structure of endangered languages undergoes a certain amount of changes at all

Contact,attrition,and structural shift57 levels:phonological,morphological,syntactic,semantic,and lexical,Hill (1980),Dorian(1989),Maher(1991),Grenoble and Whaley(1998).The changes that have been described in the literature display systematic pat-terns.As Schmidt(1985)and Maher(1991)point out,the patterns found in endangered languages are remarkably similar;many show allomorphic reduction;radical simpli?cation and regularization of certain paradigms; generalization of a single case a?x to cover various peripheral case func-tions;a tendency to eliminate verbal inˉectional a?xes;a breakdown in agreement rules;replacement of synthetic forms by analytic ones or by periphrastic constructions;and so on.Fieldwork on Oroqen done by Lindsay J.Whaley and Fengxiang Li over the past nine years has yielded data consistent with some of the characteristic features given in Maher (1991).Maher(1991:68)points out that indigenous languages undergo-ing attrition due to the encroachment of a dominant language reveal a restructuring or recon?guration of morphological and syntactic structures that display the following characteristics:

(a)Reduction in the number of allomorphs(i.e.,more invariable forms,

or fewer context sensitive rules).Increased paradigmatic regularity.

(b)Replacement of synthetic forms by analytic ones or by periphrastic

constructions.

(c)Progressive reduction in inˉectional morphology,entailing lessˉexi-

ble word order.

(d)Preference for coordinate rather than embedded constructions.

(e)Distinctive aspectual constructions in verbal systems.

For example,in Oroqen,morphological processes that have restricted applications are no longer present in younger speakers'speech.Li and Whaley(2000)give a detailed description of one of the intensive marking strategies utilized in Oroqen,namely,emphatic reduplication.Emphatic reduplication operates in Oroqen by copying the?rst syllable of an adjec-tival stem onto a CVC template and pre?xing the copied material to the adjective.If the?rst syllable of the adjective is open,then[b]is inserted into the post-vocalic slot of the CVC template.These patterns are demon-strated in example(1).

(1)bagdarin`white'bag-bagdarin`very white,white as snow'

?i3ar K n`yellow'?ib-si3ar K n`very yellow,golden yellow' kara`dark,glossy'kab-kara`very dark,glossy black'

k?3?r K n`black'k?b-k?3?r K n`very black'

For some speakers,the post-vocalic[b]in the last three forms in(1)has assimilated in voicing to the following obstruent,and so is pronounced [p].

58Li F.

Emphatic reduplication occurs only with a small number of adjective stems,perhaps only the four presented in example(1).Notably,all the adjectives are color terms,and all of them are commonly associated with the hue of certain domestic animals.For example,kara is typically used for describing dogs and horses,and?i3ar K n for dogs,though not exclu-sively.Speakers routinely reject emphatic reduplication with other adjec-tives,even if they are color terms,as shown in example(2).

(2)g K lbar K n`sky blue'*g K l-g K lbar K n

t?ú3g y?n`deep blue'*t?ú3-t?ú3g y?n

èla:r K n`red'*èb-èla:r K n

t?uturin`green'*t?ub-t?uturin

The restrictive application of reduplication has made it highly vulnera-ble to rapid loss as Oroqen becomes obsolescent.Data from four female speakers demonstrate that younger speakers no longer have emphatic re-duplication in their grammar.Our two older speakers A(70-years-old) and B(60-years-old)both used Oroqen as their primary language until their early twenties.Since that time they have increasingly used Mandarin Chinese.Both use the reduplicated adjectives in example(1),though the younger of the two does not recognize or accept the last of these forms. Our two younger speakers C(46-years-old)and D(30-years-old)no longer accept or recognize any of these forms.Though both learned Oroqen in the home as a?rst language,both have grown up and been educated in a Mandarin-dominated context.

Similar patterns were found with other morphological processes indi-cating the same process of loss.Among the nominalizers in Oroqen,-3ki is by far the most productive.It occurs with practically any verb to yield a noun.Examples are given in(3).

(3)kad K-rú-n`cut-non-future-3S'

kad K-3ki`sickle/scythe'

minú-rú-n`cut-non-future-3S'

minú-3ki`cutting board with one endˉat and the other end

concave,shaped to hold meat or with both endsˉat

and the middle concave'(usually called ninan) d?ik-tú-n`slice-non-future-3S'

d?iki-3ki`cutting board'

gèld?K-ra-n`lock-non-future-3S'

gèld?K-3ki`lock/latch'

túk-tú-n`sit-non-future-3S'

tú?ú-3ki`something to sit on'

Contact,attrition,and structural shift59 Both our older speakers A and B readily produced many examples using this and other less productive nominalizers.For example,they em-ployed the nominalizer-wun(kad K-wun`knife',tukti-wun`ladder')when they produced the forms for`knife'and`ladder'.

What is noteworthy is that quite a few of the less productive nominal-izers are no longer in the repertoire of our speakers C and D.Our speaker C only used the su?x-3ki,even in forms where older speakers do not use it.Although she retains this most productive nominalizer-3ki,and in fact uses it more generally than older speakers,she alternates between having the velar nasal and leaving it out.A similar pattern held for speaker D's speech.Only the most productive nominalizer was employed.However, for her,nasal deletion in the su?x-3ki is compulsory,which is shown in the examples in(4).

(4)l?x?-r?-n`hang something up-non-future-3S'

l?x?-ki`hook'

tú?ú-rú-n`sit-non-future-3S'

tú?ú-ki`something to sit on'

mu:-lú:`water-LOC'

mu:-lú:-ki`water bucket'

tukti-rú-n`go up/climb-non-future-3S'

tukti-ki`ladder'

gèld?K-rú-n`lock-non-future-3S'

gèld?i-ki`lock(noun)'

A clear pattern emerges in the data from the four speakers A,B,C,and D.The older speakers have a much richer repertoire of derivational mor-phology than the younger ones,and there is a gradual phonological ero-sion of the productive su?xal nominalizer-3ki that correlates with the age of the speakers,which is illustrated in the table in example(5). (5)A

B

C D

tú?ú-3ki tú?ú-3ki tú?ú-3ki/tú?ú-ki tú?ú-ki

mu:-lú:-3ki mu:-lú:-3ki mu:-lú:-3ki/m·:lú:-ki mu:-lú:-ki

tukti-wun tukti-wun tukti-3ki/tukti-ki tukti-ki

kad K-wun kad K-wun kad K-3ki/kad K-ki kad K-ki

`something to sit on'

`water bucket'

`ladder'

`sickle/scythe'

These data demonstrate,for the younger generation of Oroqen speakers,the wholesale loss of certain limited derivational strategies such

as emphatic reduplication,and the replacement of low productivity deri-vational morphemes such as -wun by equivalent,yet more productive,strategies.The drastic reduction in the number of nominalizers in the younger speakers'speech,needless to say,provides supporting evidence for princi-ple (a).In fact,we also found cases conforming to Maher's principle (b).Speci?cally,our speaker D employs the periphrastic adverbial form mani `very'in place of the emphatic reduplication strategy to express degree of intensity.Such changes are not con?ned to the realm of derivational morphol-ogy.A reduction of inˉectional morphology is also found in several of our speakers'speech displaying a pattern of varying degrees of loss,con-forming to part of principle (c),shown in example (6).

(6) a.tari 3rd .sg.múmi self-múnaxa self-reˉ.suxú-rú-n hit-non-future-3rd .sg.`He hit himself.'b.bi:1st .sg.múmi self-múnaxa self-reˉ.suxú-rú-n hit-non-future-3rd .sg.`I hit myself.'c.?i:2nd .sg.múmi self-múnaxa self-reˉ.suxú-rú-n hit-non-future-3rd .sg.`You hit yourself.'d.tari 3rd .sg.mèr K n-múhorse-def.acc.suxú-rú-n hit-non-future-3rd .sg.`He hit the horse.'e.bi:1st .sg.mèr K n-múhorse-def.acc.suxú-m hit-non-future-1st .sg.`I hit the horse.'f.?i:2nd .sg.mèr K n-múhorse-def.acc.suxú-rú-n hit-non-future-3rd .sg.

`You hit the horse.'This speaker is in her late ?fties,and the data in example (6)were col-lected in July 1997.She has lost most of her subject-verb agreement using the third person singular nonfuture form for all persons.Notice that she did use the ?rst person singular verb form in sentence (6e).The examples in (6d)to (6f )were collected after we reminded her of the agreement rule by feeding her the correct forms.Even so,she still used the 3rd person singular non-future form for the second person as is shown in sentence (6f ).However,she does retain the case marking system.She used the ac-cusative markers on the noun `horse'unfailingly.In contrast,a slightly

60Li F.

younger speaker,who is 44-years-old,has lost not only

subject-verb agreement,but part of the case system as well,which is illustrated in the

examples given in examples (7)to (10).(7) a.bi:1st .sg d?úktú-yúfood-indef.acc.

d?úb-tú-n /d?úb-tú-m eat-non-future-3rd .sg./eat-1st .sg.

`I am eating (food).'

b.?i:2nd .sg

d?úktú-yúfood-indef.acc.d?úb-tú-n eat-non-future-3rd .sg.

`You are eating (food).'

c.n?nin 3rd .sg

d?úktú-yúfood-indef.acc.d?úb-tú-n eat-non-future-3rd .sg.

`He is eating (food).'

d.bu:1st .pl.excl.d?úktú-yúfood-indef.acc.

d?úb-tú-n eat-non-future-3rd .sg.

`We are eating (food).'e.biti 1st .pl.incl.

d?úktú-yúfood-indef.acc.d?úb-tú-n eat-non-future-3rd .sg.

`We are eating (food).'

f.?u:2nd .pl.d?úktú-yúfood-indef.acc.

d?úb-tú-n eat-non-future-3rd .sg.

`You are eating (food).'

g.tari-l 3rd .pl.d?úktú-yúfood-indef.acc.d?úb-tú-n

eat-non-future-3rd .sg.

`They are eating (food).'The examples in (7)show that almost

all of the

agreement

markers

between subject and verb are lost in this speaker's speech.The only excep-tion is the ?rst person singular in sentence (7a),which she uses some of

the time.Curiously,the same behavior can be observed in her use of the ?rst person plural exclusive agreement marking,which is demonstrated in

example (8).(8) a.bi:1st .sg.d?anda-rú-n sing-non-future-3rd .sg.

`I am singing.'

b.?i:2nd .sg.d?anda-rú-n sing-non-future-3rd .sg.

`You are singing.'

c.n?nin 3rd .sg.d?anda-rú-n

sing-non-future-3rd .sg.

`He is singing.'Contact,attrition,and structural shift 61

d.

biti 1st .pl.incl.d?anda-rú-n sing-non-future-3rd .sg.`We are singing.'e.

bu:1st .pl.excl.d?anda-rú-n /d?anda-rú-wun sing-non-future-3rd .sg./sing-non-future-1st .pl.`We are singing.'f.

?u:2nd .pl.d?anda-rú-n sing-non-future-3rd .sg.`You are singing.'g.tari-l 3rd .pl.d?anda-rú-n sing-non-future-3rd .sg.`They are singing.'

Clearly,all of the agreement markers are lost in sentences (8a)to (8g),except for sentence (8e)in which case the speaker sometimes put the agreement marker in.When asked what the di¨erence is between the two forms with and without the agreement marker,the speaker explains that older people prefer forms with the agreement marker,and it is too verbose to talk that way.This indicates that for speakers like her,it is not a matter of imperfectly learning the grammatical system of their L1.They use certain structures by choice,which is counter evidence to some of the claims made in the literature on language attrition situa-tions (e.g.,Dorian 1989).In terms of case markings,the speaker seems to have a preference for the inde?nite accusative marker over the de?nite accusative case marker.Notice that in example (7),the case marking used on the direct object `food'is the inde?nite accusative marker `-yú'.This is no accident,which can be proven by the sentences in example (9).

(9) a.

n?nin 3rd .sg.d?axal thing ?ilki-rú-n wash-non-future-3rd .sg.`He is washing something.'b.n?nin 3rd .sg.túti clothes ?iki-rú-n wash-non-future-3rd .sg.`He is washing clothes.'c.n?nin 3rd .sg.min-3i 1st .sg.-poss.túti-yi clothes-indef.acc.?iki-rú-n wash-non-future-3rd .sg.`He is washing my clothes.'d.n?nin 3rd .sg.min-3i 1st .sg.-poss.túti-wúclothes-def.acc.?iki-rú-n wash-non-future-3rd .sg.`He is washing my clothes.'62Li F.

e.bi:1st .sg.min-3K 1st .sg.-poss.túti-yi múmúxan clothes-inde

f.acc.1st

.sg.reˉ.

?iki-m wash-non-future-3rd

.sg.`I am washing my own clothes.'

In sentences (9a)and (9b),there is no accusative

marking on the di-rect object `thing'and `clothes'respectively.When a determiner is added,the speaker produced the sentences (9c)to (9e).The determiner seemed to have some

sort of triggering e¨ect inducing the use of the accusative markers in all of the three examples.However,the speaker apparently has a preference for the inde?nite accusative marker over the de?nite one,though she switches between the two shown in sentences (9c)to (9e)although the context requires the de?nite accusative marker.Also,

in sentence

(9e)

we again

see

the ?rst person singular agreement marker on the verb showing up.It is interesting to note that a deletion of the

consonant in the coda position of the initial syllable in the verb ?ilki-rú-n `wash'occurred in sentences (9b)to (9e),a phenomenon observed in other speakers as discussed earlier in the case of nominalizers.In both

cases,the deleted consonant is preceded by the voiceless velar stop.

The missing accusative marking in sentence (9a)

is not an

isolated

case.In

fact,this and some other speakers of a comparable age rou-

tinely leave out accusative markers,as shown in the sentences in example (10).(10) a.bi:1st .sg.araxi wine im-nú-n drink-non-future-3rd

.sg.

`I am drinking wine.'b.?i:2nd .sg.

araxi wine im-nú-n

drink-non-future-3rd .sg.

`You are drinking wine.'c.n?nin 3rd .sg.araxi wine im-nú-n drink-non-future-3rd

.sg.

`He is drinking wine.'d.biti 1st .pl.incl.araxi wine im-nú-n drink-non-future-3rd .sg.

`We are drinking wine.'

e.bu:1st .pl.excl.araxi wine im-nú-n drink-non-future-3rd

.sg.

`We are drinking wine.'

f.n?ntin /tari-l 3rd .pl.araxi wine im-nú-n

drink-non-future-3rd .sg.

`They are drinking wine.'Contact,attrition,and structural shift 63

The sentences in example (10)demonstrate that for this speaker,the accusative case marking is no longer obligatory.In fact,she only uses it infrequently.Notice also,that in example (10),all of the agreement markers have been leveled,reducing them to the default choice of the third person singular form.It is safe to say that this particular speaker has lost most of the agreement case distinctions.When asked about the di¨erences between m?:-duki ,m?:-lak ,m?:-li:,and m?:-ki the speaker said without hesitation that they all meant the same thing,despite the fact that in each case we have the root morpheme m?:`tree'plus a case marker:-duki `ablative (from)'-la:k `loco-ablative (from inside)',-li `pro-lative (pass by,along the side)',and -ki `allative (to)'.None of these cases is in the grammatical system of this speaker.This is also true with another speaker comparable in age with this speaker.Both speakers learned Oro-qen as their ?rst language at home.They did not learn Chinese until they started elementary school at the age of seven or eight.It should be pointed out that the language of instruction from grade one through grade ?ve was Oroqen.This means that their dominant language was Oroqen up until they were around ?fteen years of age,indicating that they lost those forms in a very short period of time,about three decades.A systematic pattern emerges among the speakers we have worked with over the years.The varying degree of loss of the grammatical system cor-relates quite closely with age.This particular speaker is representative of the speakers aged 45or younger,while the earlier speaker is typical of those who are between 45and 55,and those who are sixty or older still have the grammatical system mainly intact.All of the older speakers we have worked with so far never failed to use the traditional agreement markers,and they always readily rejected any violations of the agreement rules.The following paradigm was elicited from a 71-year-old speaker in Baiyina in Huma County,Heilongjiang Province.

(11) a.

bi:1st .sg.d?anda-m sing-non-future.1st .sg.`I am singing.'b.?i:2nd .sg.d?anda-ni sing-non-future.2nd .sg.`You are singing.'c.n?nin 3rd .sg.d?anda-rú-n sing-non-future-3rd .sg.`He is singing.'d.bu 1st .pl.excl.d?anda-rú-w sing-non-future-1st .pl.excl.`We are singing.'64Li F.

e.miti 1st .pl.incl.d?anda-rap sing-non-future-1st

.pl.incl.

`We are singing.'

f.su 2nd

.pl.d?anda-ra-y

sing-non-future-2nd .pl.

`You are singing.'g.n?ntin 3rd

.pl.d?anda-ra

sing-non-future.3rd .pl.

`They are singing.'The data from speakers with di¨erent degrees of conservatism in Oroqen presented so far show a clear tendency that the younger speakers are moving

away from inˉectional devices and favoring unmarked forms,showing a preference for

periphrastic

constructions over synthetic ones to express

grammatical relations.For instance,they favor the use of the

lexeme mani `very'instead of the emphatic reduplication process in the sentences in example (9)for expressing degree of emphasis.The data reveal a restructuring and recon?guration of morphological and syntac-tic structures

that display

characteristics that provide some insight into

longitudinal aspects of language obsolescence.Further investigation is

needed to answer some intriguing questions.For instance,we do not fully understand why when subject-verb agreement is lost,second person seems to go ?rst,followed by ?rst person.It is possible that the ?rst person not

only has a higher frequency of occurrence but has ego centric prominence

as well,resulting in its being more salient,which provides a certain degree

of resistance

to loss.Why third person singular is chosen as the default

agreement for all persons is unclear.One possible explanation could be that third person is less deictic.Consequently,it is relatively more stable (Lenore Grenoble personal communication).It is also unclear why the de?nite accusative case marker is lost ?rst.It is likely that the de?nite accusative case is more cognitively demanding in production since it is semantically more complex.One can argue that the unmarked form is

normally retained or lost last.This means that the inde?nite accusative

case is unmarked with respect to the de?nite accusative

case and the third

person singular

agreement marking is unmarked in relation to the other

agreement markers.Frequency of occurrence could also be a factor since third person

has the highest frequency (Bradley personal communica-tion).One of our speakers once commented that when children learn Or-oqen,they initially only use the third person singular agreement forms of

all verbs.

It is possible that frequency of occurrence,saliency,and func-

tional load all have a role to play in the retention and rate of loss of the

grammatical forms.It would be of bene?t to sort out what goes ?rst and Contact,attrition,and structural shift 65

66Li F.

why in terms of the various grammatical components of an obsolescing language.It is equally important to answer the question:What factors led to those changes and why the changes took place in such a remark-ably short period of time?Answers to such questions would help unravel the complexity of language obsolescence taking place in a number of other seriously endangered languages in China.

https://www.360docs.net/doc/cd6693907.html,nguage contact

As Seliger and Vago(1991)pointed out,many,though not all,of the lin-guistic changes attendant to attrition are simpli?catory in nature.This is de?nitely true in the case of Oroqen.The patterns evident in this simpli?-cation process are remarkably similar to what have already been docu-mented elsewhere,for example,Schmidt(1985)as is mentioned earlier. However,not all of the changes in Oroqen are explainable through such attrition induced internal motivations.

I argue that,in the case of Oroqen,some of the changes are exter-nally motivated because Oroqen has had massive contact for an extended period of time with several genetically related and non-genetically related languages,such as Chinese(Sinitic),Dagur(Mongolic),Ewenki(Machu-Tungusic),and to some extent Russian(Slavic)in the Lesser Hinggan Mountain region.It is eminently clear that for all speakers(except a few elderly speakers),Oroqen is at best a second language,which is being rapidly replaced by Mandarin Chinese.Section three of this article is an attempt to identify the changes taking place as speakers replace one lan-guage by another,with an emphasis on the role of the contact languages upon the phonological,morphological and syntactic changes which take place,as well as the rate,extent and order in which these changes occur. The situation Oroqen o¨ers in this respect is quite complex because all theˉuent Oroqen speakers are multilingual,at least in Oroqen,Mandarin Chinese,Dagur,and most importantly,some other Tungusic variety, such as Solon or Ewenki.

Among the linguistic e¨ects common to situations of language con-tact are convergence,loss of morphological and syntactic complexity, transfer,interference,and an overall increase in semantic transparency (Dorian1989).In the case of Oroqen,we observe borrowing,including structural borrowing.That is to say,some of the structural changes in this moribund language may be the result of inˉuence from linguistic patterns of the dominant languages.Before the encroachment of Man-darin Chinese in the1950s,Oroqen had had a lengthy and persistent contact with the Dagurs.The two ethnic groups coexisted in a symbiotic

Contact,attrition,and structural shift67 relationship for centuries.The traditionally nomadic Oroqen relied on the sedentary Dagur for certain agricultural goods,while in exchange supply-ing the Dagur with pelts and meat.The commercial relationship,while mutually bene?cial,established Dagur as the dominant language,and it became the norm for Oroqen speakers to learn to speak Dagur,resulting in the borrowing of certain grammatical structures.A case in point is the emphatic reduplication strategy to mark intensity seen in example(1), which is no longer present in the grammatical system of younger speakers of Oroqen as is discussed above.Whaley and Li(2000)demonstrated quite convincingly that Oroqen borrowed the emphatic reduplication strategy from Dagur,a Mongolic language.

Dagur has a formally identical reduplication strategy that copies the ?rst syllable and inserts[b]or[m]in the coda position of the pre?x (Zhong1982),as is illustrated in the examples in(12).

(12)xulam`red'xub xulam`thoroughly red'

t?i?a:n`white't?im t?i?a:n`very white'

dasu3`sweet'dab dasu3`really sweet'

súru:3`cool'súb súru:3`really cool'

xordu3`fast'xob xordu3`very fast'

Like Oroqen,Dagur employs reduplication to indicate intensity.How-ever,the process in Dagur is fully productive and operates on adjectives denoting di¨erent sorts of properties,not just colors.

The Oroqen lexicon has taken on many Dagur words,and Oroqen grammar has borrowed from Dagur,particularly in the area of deriva-tional morphology.Thus,the borrowing of reduplication can be seen as part of a more general Dagur inˉuence on Oroqen grammatical structure. As a point of comparison,consider another example of morphological borrowing.Dagur has a plural marker-nur2used for kinship terms and human nouns illustrated in example(13).

(13)(from Zhong1982:33)

úkúú`sister'

úkúú-nur`sisters'

gut?`comrade'

gut?-nur`comrades'

Oroqen uses the phonologically similar su?x-nVr,but it is only used for kinship terms.Among Tungusic languages,the su?x is only found in Oroqen and some dialects of Ewenki which are also in contact with Dagur.This fact indicates that the su?x is a borrowing.Some examples from Oroqen are given in example(14).

68Li F.

(14)(Hu1986:56)

naat?è`uncle(on mother's side)'

naat?è-n?r`uncles(on mother's side)'

amaakaa`uncle(on father's side)'

amaakaa-nar`uncles(on father's side)'

júújú`grandfather'

júújú-núr`grandfathers and those of their generation'

In Dagur,the marker-nur simply signals plurality of kinship terms and other human nouns.The borrowed marker-nVr in Oroqen,how-ever,is more restricted in two ways.It is used solely with kinship terms, and it has taken on other connotations beyond plurality.On the one hand,it can indicate an exhaustive set.The word naat?è-n?r in example (14)thus connotes all the uncles on the mother's side together.The su?x can also indicate age association,as in the?nal form in(14)júújú-núr, which designates grandfathers and everybody else belonging to their generation.

The instance of the-nur borrowing is reminiscent of the facts surround-ing the borrowing of reduplication.In both cases,a morphological strat-egy is borrowed,but in a more restricted way such that in Oroqen it can only be applied to a subset of those forms to which it can be applied in Dagur.Furthermore,perhaps as part of its limited distribution in Oro-qen,it takes on connotations that it did not have in Dagur.This pattern, which we have only discussed with respect to two morphological borrow-ings,appears to hold true for other cases of probable structural borrow-ing that we have identi?ed to date.

The sort of structural inˉuence that Dagur has had on Oroqen re-quires an extended period of relatively intimate contact.It is useful here to review the history of these groups which points to just this type of interaction.

Both the Dagurs and the Oroqens are believed to originate from the re-gion north of the Amur River,that is,in present day Russia.They both crossed the mighty Amur River several hundred years ago(most likely in the1600s)and spread over the Greater and Lesser Hinggan Mountains in Manchuria.Janhunen(1997)suggests that migrations of small Dagur populations occurred in tandem with the Oroqen and Solon migrations. Regardless,it is widely accepted that all these groups have co-existed harmoniously in Inner Mongolia and the Northeast of China for several centuries.

Trading among them was ubiquitous,usually involving the exchange of fur,game products and animal hide handicrafts from the Oroqens and Ewenkis and animal husbandry or agricultural products from the Dagurs.

Contact,attrition,and structural shift69 The frequency of the trading led to multilingualism,and some mixing of the populations through intermarriages.

Since the borrowing being discussed here is structural rather than lexical in nature,massive bilingualism on the part of the Oroqen speakers in the lending language persisting over a long period of time is a crucial prerequisite.

Another social factor frequently invoked in accounting for borrowings across languages,especially languages belonging to di¨erent families,is a prestigious status of the source language.As Moravcsik(1978:109)puts it,in perhaps an overstatement,``nothing can be borrowed from a lan-guage which is not regarded[as]prestigious by speakers of the borrow-ing language.''The Dagur people have historically held the necessary position of prestige:According to Janhunen(1997),``since Qing times (1644±1911),the Dagurs have been known as an ethnic group interested in acquiring higher learning through dominant languages such as Man-chu and Chinese.''This may help explain why the Qing emperor en-trusted the Dagurs with the control of the ethnically diverse diaspora army sent to guard Chinese borders against the potential invaders in bor-dering areas.

Dagur is not the only contact language that has had an impact on the structure of Oroqen.In more recent time,Mandarin Chinese has un-doubtedly inˉuenced Oroqen.Although the period of time that Mandarin Chinese has been in intense contact with Oroqen is relatively short,it seems to have had a strong impact on its grammatical structure.We found that for most speakers of Oroqen,the plural marker is no longer required,which could be seen as the consequence of Chinese inˉuence (cf.,Whaley forthcoming).Although Hu(1986)documented both-l and -sal as plural markers in Oroqen,they are no longer readily attested in any of the Oroqen dialects.As Whaley(forthcoming)points out,a zero morpheme is the unmarked,preferred plural marking in all of the Oroqen dialects.They also noted that Oroqen is the only Northwestern Tungusic language in which unmarked plurals are more common than su?xa-tion.Assuming that Hu's(1986)description is accurate,it is noteworthy that Oroqen has moved further on the path to losing the plural marker. We have yet to elicit any naturally occurring examples of Oroqen in which the plural markers are employed.The speakers we have worked with from southeastern,western and central Oroqen dialect regions occasionally very reluctantly accepted the plural marker-l and-sal in a highly restricted number of lexical items,most of which denote animate beings with a high frequency of occurrence.The only speaker who readily accepted forms with the plural markers-l and-sal was from the north-eastern Oroqen dialect region,speci?cally from Baiyina.Some of the

examples are :kumaxa-l `deer',utú-l `sons',ilga-l `ˉowers',búyú-xúl `per-sons',ahi-húl `women',utú-húl `sons'.Even for her,the preferred form is the analytic construction of baran kumaxa `many deer'.It is highly likely that this loss is contact induced.Chinese inˉuence is also manifested in other ways.It seems to have im-pacted those areas that had the longest and most intensive contact with Chinese much more extensively,notably the southeastern and central dia-lect regions,more than the areas that did not have any Han Chinese until after the settlement in the late 1950s and early 1960s.Our speaker from the central dialect region used the adverb ma?a3,which is a Chinese bor-rowing meaning `immediately'spontaneously without noticing it.When fed the Oroqen word diyald?i meaning the same thing,he accepted it,but strongly prefers the Chinese borrowing.Interestingly enough,our speakers from the western and northeastern dialect regions adamantly re-jected the Chinese form insisting that it is not an Oroqen word.Even in the northeastern dialect region where Oroqen is preserved the best,we saw strong Chinese inˉuence,which is shown in the examples in (15).

(15) a.

?i you t K mana tomorrow 3únú-ni go-2nd .sing.prest.yúni question part.-2nd sing.present `Are you going tomorrow or not?'b.yabu?a walk-past ha?i still-be yú?a question part.-past `Did you go or not?'In example (15),we have two examples of the A-not-A question forma-tion in Oroqen.Notice that the speaker used the Chinese haishi `still be:or not'in sentence (15b).She did so without realizing it at all until it was pointed out to her.This speaker feels at ease with both languages.In other words,she possesses native pro?ciency in both Chinese and Or-oqen.This kind of phenomenon indicates that when a speaker reaches a certain level of bilingual pro?ciency,borrowing between the languages is much easier than is generally assumed in the literature.Thus it may not take a very long time for a language to shift to a completely di¨erent ty-pological pattern in its grammatical structures.Central to the rate of such structural shifts are sociolinguistic factors.

4.Conclusion

Although some linguists would consider structural similarity and func-tional congruence as important factors in cases of grammatical borrowing

70Li F.

Contact,attrition,and structural shift71 (e.g.,Weinreich[1953]),I argue that Oroqen provides a counter-example. Dagur has both su?xes and pre?xes whereas Oroqen is purely su?xal, with the exception of emphatic reduplication.Since,in terms of genetic a?liation,Oroqen,the borrowing language,and Dagur,the lending lan-guage,belong to two di¨erent families,Tungusic and Mongolic respec-tively,typological distance and structural similarity do not obviously hold in this case.Needless to say,the di¨erence between Oroqen and Chi-nese is even greater in terms of both genetic relatedness and structural similarities.In this respect,I agree with Thomason and Kaufman(1988: 35)who contend that``it is the sociolinguistic history of the speakers, and not the structure of their language,that is the primary determinant of the linguistic outcome of language contact.Purely linguistic consid-erations are relevant but strictly secondary overall.''The case of Oroqen borrowing provides evidence in support of Thomason and Kaufman's contention.

These phenomena pose the question:What factors led to those changes and why the changes took place in such a remarkably short period of time?The complex set of conditions responsible for the restructuring are only partly explainable by internally and externally motivated principles proposed in the literature.A profound understanding of the situation must take account of the dynamic changes that take place in not only lin-guistic structures but in the social conditions as well.There is a range of social factors that contribute to language obsolescence and structural shifts.In the case of Oroqen,encroaching bilingualism with a powerful dominant language(along with schooling and social mobility),aban-donment of traditional lifestyle and values,settlement,dispersion,cross-marriages,drastic reduction of?rst language use in social functions (even at home),failure of children to acquire the traditional mother tongue,lack of social cohesion as a barrier against the rival dominant language,psychological perception of the traditional language as a liabil-ity for upward social mobility,and a prevalent negative attitude towards the cultural traditions of the dominated population are among the most prominent factors that lead to not only language attrition but particular type of changes as well.

The conditions responsible for the changes in Oroqen are mostly so-ciolinguistic.Oroqen was surrounded by several languages for centuries without su¨ering any attrition,which is attributable to the cohesion of the community,its self-imposed rule forbidding intermarriages with other ethnic groups and its strong adherence to traditional lifestyle and values prior to settlement in the late1950s.However,dramatic social changes in the1950s and1960s quickly resulted in Oroqen's very rapid ceding to the superstratum language Mandarin Chinese.The construction of a

72Li F.

railroad,massive Chinese migration to the area due to the development of the logging and mining industries,settlement of the Oroqens,schooling in Chinese,extensive intermarriage with nearby ethnic groups,abandon-ment of traditional values and lifestyle,and the local government's lack of interest in maintaining the Oroqen language and cultural traditions led to a situation characterized by an increasing use of Mandarin Chinese in more and more situations,which quickly brought about the current pro?ciency continuum determined by age among those who still speak Oroqen.The diminishing use of Oroqen severely limits the younger generation's exposure to the language,which is the major cause for their imperfect learning of their obsolescing?rst language.It is quite obvious that the Oroqen language in China is on an irreversible course to its de-mise,and we are far short of attaining our goal of having a full picture of the conˉuence of factors that led to its current sad state of a¨airs.

In this article I only presented a few salient characteristic features.I would like to emphasize that what is discussed here is a sampling which should not be construed as an attempt to provide a full picture,but rather to illustrate the attrition and contact phenomena in this rapidly dis-appearing language,contributing to the general e¨ort to achieve a com-plete description and explanation of contact induced changes and changes attendant to the attrition process.

The rapid changes taking place in languages like Oroqen make it imperative that the nature of the speech community be speci?ed in far more detail than it is now and as quickly as possible.We can already see that extensive language change in these particular languages whose speaker community is constituted by bi-or multilingual linguistic and ethnic minorities but the details need to be documented and the paths of change need to be examined.A lot more work needs to be done and done quickly before the languages in question cease to exist.

California State University Notes

*I would like to thank Juha Janhunen and David Bradley who read my article and gave very useful comments.I would also like to thank Graham Thurgood and Lenore Greno-ble for helpful discussions.I am indebted to Lindsay J.Whaley who worked with me in collecting the data on Oroqen used in this article.I am very grateful to all of the Oroqen consultants I have worked with over the past nine years in Inner Mongolia and north-east of China.This project was partially funded by NSF grants SBR9710091and BCS0220354.

Contact,attrition,and structural shift73 1.A number of Tungusic scholars treat Oroqen as an Evenki dialect.It is probably more

appropriate to refer to this variety as one of the dialects on a continuum that includes all of the sixty or so Evenki dialects spoken in both China and Siberia.For instance, Janhunen(1997)recognizes four dialectal and geographical subgroups of Oroqen,and treats them as idioms within the conglomeration of Ewenki varieties.

2.Juha Janhunen pointed out to me that``in Dagur,-nur is used to mark the plural of per-

sons,mainly kin,or groups associated with a kinship category.By contrast,the regular plural-sul(which is a borrowing from Solon)does not have such restrictions.''(Juha Janhunen personal communication)Notice that in Oroqen,-nur is even more restricted.

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ADAMS常见问题

ADAMS 使用常见问题 1、ADAMS中的单位的问题 开始的时候需要为模型设置单位。在所有的预置单位系统中,时间单位就是秒,角度就是度。可设置: MMKS--设置长度为毫米,质量为千克,力为牛顿。 MKS—设置长度为米,质量为千克,力为牛顿。 CGS—设置长度为厘米,质量为克,力为达因。 IPS—设置长度为英寸,质量为斯勒格(slug),力为磅。 2、如何永久改变ADAMS的启动路径? 在ADAMS启动后,每次更改路径很费时,我们习惯将自己的文件存在某一文件夹下;事实上,在Adams的快捷方式上右击鼠标,选属性,再在起始位置上输入您想要得路径就可以了。 3、关于ADAMS的坐标系的问题。 当第一次启动ADAMs/View时,在窗口的左下角显示了一个三视坐标轴。该坐标轴为模型数据库的全局坐标系。缺省情况下,ADAMS/View用笛卡儿坐标系作为全局坐标系。ADAMS/View将全局坐标系固定在地面上。 当创建零件时,ADAMS/View给每个零件分配一个坐标系,也就就是局部坐标系。零件的局部坐标系随着零件一起移动。局部坐标系可以方便地定义物体的位置,ADAMS/View也可返回如零件的位置——零件局部坐标系相对于全局坐标系的位移的仿真结果。局部坐标系使得对物体上的几何体与点的描述比较方便。物体坐标系不太容易理解。您可以自己建一个part,通过移动它的位置来体会。 4、关于物体的位置与方向的修改 可以有两种途径修改物体的位置与方向,一种就是修改物体的局部坐标系的位置,也就就是通过MODIFY物体的position属性;令一种方法就就是修改物体在局部坐标系中的位置,可以通过修改控制物体的关键点来实现。我感觉这两种方法的结果就是不同的,但就是对于仿真过程来说,物体的位置就就是质心的位置,所以对于仿真就是一样的。 5、关于ADAMS中方向的描述。 对于初学的人来说,方向的描述不太容易理解。之前我们都就是用方向余弦之类的量来描述方向的。在ADAMS中,为了求解方程就是计算的方便,使用欧拉角来描述方向。就就是用绕坐标轴转过的角度来定义。旋转的旋转轴可以自己定义,默认使用313,也就就是先绕z轴,再绕x轴,再绕z轴。 6、Marker点与Pointer点区别 Marker:具有方向性, 大部分情況都就是伴随物件自动产生的,而 Point不具有方向性, 都就是用户自己建立的;Marker点可以用来定义构件的几何形状与方向,定义约束与运动的方向等,而Point点常用来作为参数化的参考点,若构件与参考点相连,当修改参考点的位置时,其所关联的物体也会一起移动或改变。

adams常用函数

1.step可能是最常用的: step(time,0,0,1,50)+ step(time,4,0,6,-100)+ step(tme,9,0,10,50) 函数原形STEP(A,x1,h1,x2,h2) 解释:由数组A的x值,生成区间(x1,h1)至(x2,h2)之间的阶梯曲线,返回y值的数据。 举个常用的例子。 比如STEP(time,1,0,2,100) time在adams中是个递增的变量,相当于一个数组。那么step的返回值就是随着time变化的值。 这个例子将表示在time从(1,2)的过程中,返回值将从0,100。看看例子,两个小球,一个使用step 函数设置了位移,另外一个是参考。当然,这个变化过程,adams使用了缓和的图形,从其位移图中可以看出来。step既然是个返回值,就可以使用加减法了。如上例,如果设置下面的小球的位移如下:STEP(time,1,0,2,100)+step(time,2,0,3,400)+step(time,3,0,4,-200) 2.以前用过碰撞函数,有单向和双向函数的区分,其中系统的球面等碰撞为其特例! IMPACT (Displacement Variable, Velocity Variable, Trigger for Displacement Variable, Stiffness Coefficient, Stiffness Force Exponent, Damping Coefficient, Damping Ramp-up Distance) BISTOP (Displacement Variable, Velocity Variable, Low Trigger for Displacement Variable, High Trigger for Displacement Variable, Stiffness Coefficient, Stiffness Force Exponent, Damping Coefficient, Damping Ramp-up Distance) 3.if函数 这个函数最好不要使用,他的使用会带来突变,会使运算的时候不收敛。不过应急的时候还是可以一用。 if(time-1:1,0,if(time-2:0,-1,-1)) IF(Expression1: Expression2, Expression3, Expression4) adams要计算Expression1的值: 如果他的值小于0,则执行Expression2语句,如果Expression1的值等于0,则执行Expression3语句,如果Expression1的值大于0,则执行Expression4语句 我得if语句的意思是:如果时间小于1的时候,加速度为1,如果时间为1,加速度为0,如果时间大于1小于2,则加速度为0,如果时间大于、等于2则,加速度为-1 4. 我得一个想法 就是利用sign函数构造 比较常用的是给机构加上一个与运动方向相反的作用力等等可以先测量施加力对象的运动速度,然后利用速度的变化,插入measure到sign函数里面就可以获得与运动方向相反的作用力

ADAMS-STEP函数

在定义接触力时Normal Force有两个选项: 1、Restitution(Define a restitution-based contact); 2、Impact(Define an impact contact) 第二个选项就是利用IMPACT函数,它能方便地表达那种间歇碰撞力 (即达到某一位移值才激发的碰撞力)。 它的参数意义及力学基础: One-sided Impact (IMPACT) 1、理解:用只抗压缩的非线性的弹簧阻尼方法近似计算出单边碰撞力。 2、格式:IMPACT (Displacement Variable, Velocity Variable, Trigger for Displacement Variable, Stiffness Coefficient, Stiffness Force Exponent, Damping Coefficient, Damping Ramp-up Distance) 3、参数说明: Displacement Variable 实时位移变量值,通过DX、DY、DZ、DM等函数实时测量。 Velocity Variable 实时速度变量值,通过VX、VY、VZ、VM等函数实时测量。 Trigger for Displacement Variable 激发碰撞力的位移测量值。 Stiffness Coefficient or K 刚度系统。 Stiffness Force Exponent 非线性弹簧力指数。 Damping Coefficient or C 阻尼系数。

Damping Ramp-up Distance 当碰撞力被激发阻尼逐渐增大的位移值。 4、Impact函数的力学基理: IMPACT函数值由自变量值决定其有无: IMPACT = Off if s > so On if s <=so IMPACT函数的数学计算公式为: MAX {0, K(so - s)**e - Cv *STEP (s, so- d, 1, so ,0)} 参数说明: s ——位移变量 v ——速度变量 so——碰撞力的激发位移值 K ——刚度系数 C ——阻尼系数 D——阻尼逐渐增大的位移值

ADAMS中的函数

ADAMS/View中系统提供的数学函数大致分类介绍如下。 (1)基本数学函数 ABS(x) 数字表达式x的绝对值 DIM(x1,x2) x1>x2时x1与x2之间的差值,x1<x2时返回0 EXP(x) 数字表达式x的指数值 LOG(x) 数字表达式x的自然对数值 LOG10(x) 数字表达式x的以10为底的对数值 MAG(x,y,z) 向量[x,y,z]求模 MOD(x1,x2) 数字表达式x1对另一个数字表达式x2取余数 RAND(x) 返回0到1之间的随机数 SIGN(x1,x2) 符号函数,当x2>0时返回ABS(x),当x2<0时返回-ABS(x) SQRT(x) 数字表达式x的平方根值 (2)三角函数 SIN(x) 数字表达式x的正弦值 SINH(x) 数字表达式x的双曲正弦值 COS(x) 数字表达式x的余弦值 COSH(x) 数字表达式x的双曲余弦值 TAN(x) 数字表达式x的正切值 TANH(x) 数字表达式x的双曲正切值 ASIN(x) 数字表达式x的反正弦值 ACOS(x) 数字表达式x的反余弦值 ATAN(x) 数字表达式x的反正切值 ATAN2(x1,x2) 两个数字表达式x1,x2的四象限反正切值

(3)取整函数 INT(x) 数字表达式x取整 AINT(x) 数字表达式x向绝对值小的方向取整 ANINT(x) 数字表达式x向绝对值大的方向取整 CEIL(x) 数字表达式x向正无穷的方向取整 FLOOR(x) 数字表达式x向负无穷的方向取整 NINT(x) 最接近数字表达式x的整数值 RTOI(x) 返回数字表达式x的整数部分 位置/方向函数位置/方向函数用于根据不同输入变量计算有关位置或方向的参数。ADAMS/View中系统提供的位置/方向函数分类介绍如下。 (1)位置函数 LOC_ALONG_LINE 返回两点连线上与第一点距离为指定值的点 LOC_CYLINDRICAL 将圆柱坐标系下坐标值转化为笛卡儿坐标系下坐标值 LOC_FRAME_MIRROR 返回指定点关于指定坐标系下平面的对称点 LOC_GLOBAL 返回参考坐标系下的点在全局坐标系下的坐标值 LOC_INLINE 将一个参考坐标系下的坐标值转化为另一参考坐标系下的坐标值并归一化 LOC_LOC 将一个参考坐标系下的坐标值转化为另一参考坐标系下的坐标值

ADAMS部分常用函数的说明

ADAMS常用函数的说明 一、几个常用函数的说明 1、 STEP函数 格式:STEP (x, x0, h0, x1, h1) 参数说明: x ―自变量,可以是时间或时间的任一函数 x0 ―自变量的STEP函数开始值,可以是常数或函数表达式或设计变量; x1 ―自变量的STEP函数结束值,可以是常数、函数表达式或设计变量; h0 ― STEP函数的初始值,可以是常数、设计变量或其它函数表达式; h1 ― STEP函数的最终值,可以是常数、设计变量或其它函数表达式。 2、 IF函数 格式:IF(表达式1: 表达式2, 表达式3, 表达式4) 参数说明: 表达式1-ADAMS的评估表达式; 表达式2-如果的Expression1值小于0,IF函数返回的Expression2值; 表达式3-如果表达式1的值等于0,IF函数返回表达式3的值; 表达式4-如果表达式1的值大于0,IF函数返回表达式4的值;

例如:函数IF(time-2.5:0,0.5,1) 结果:0.0 if time < 2.5 0.5 if time = 2.5 1.0 if time > 2.5 3、AKISPL函数 格式:AKISPL (First Independent Variable, Second Independent Variable,Spline Name, Derivati ve Order) 参数说明: First Independent Variable ——spline中的第一个自变量 Second Independent Variable(可选) ——spline中的第二自变量 Spline Name ——数据单元spline的名称 Derivative Order(可选) ——插值点的微分阶数,一般用0就可以了 例如: function = AKISPL(DX(marker_1, marker_2), 0, spline_1) spline_1用下表中的离散数据定义:

adams常见函数总结

ADAMS常用函数总结 在使用adams的过程中,由于函数比较多,大概有11种之多,如1、Displacement Fu nction 2、Velocity Functions 3、Acceleration Functions 4、Contact Functions 5、Spline Functions 6、Force in Object Functions 7、Resultant Force Functi ons 8、Math Functions 9、Data Element Access 10、User-Written Subroutine Invocation 11、Constants & Variables。 在adams中也有帮助文档,但是对于初学者来说还是有一定的难度的,基于这种情况我总结了一下几种常用的函数,希望能够起到抛砖引玉的作用! 1、STEP函数 格式:STEP (x, x0, h0, x1, h1) 参数说明: x―自变量,可以是时间或时间的任一函数 x0 ―自变量的STEP函数开始值,可以是常数或函数表达式或设计变量; x1 ―自变量的STEP函数结束值,可以是常数、函数表达式或设计变量 h0 ―STEP函数的初始值,可以是常数、设计变量或其它函数表达式 h1 ―STEP函数的最终值,可以是常数、设计变量或其它函数表达式 2、IF函数 格式:IF(表达式1: 表达式2, 表达式3, 表达式4) 参数说明: 表达式1-ADAMS的评估表达式; 表达式2-如果的Expression1值小于0,IF函数返回的Expression2值; 表达式3-如果表达式1的值等于0,IF函数返回表达式3的值; 表达式4-如果表达式1的值大于0,IF函数返回表达式4的值; 例如:函数IF(time-2.5:0,0.5,1) 结果:0.0 if time < 2.5 0.5 if time = 2.5 1.0 if time > 2.5 3、AKISPL函数 格式:AKISPL (First Independent Variable, Second Independent Variable,Spline Name, Derivative Order) 参数说明: First Independent Variable——spline中的第一个自变量 Second Independent Variable (可选) ——spline中的第二自变量Spline Name——数据单元spline的名称 Derivative Order (可选) ——插值点的微分阶数,一般用0就可以function = AKISPL(DX(marker_1, marker_2, marker_2), 0, spline_1) spline_1用下表中的离散数据定义 自变量x 函数值y -4.0 -3.6 -3.0 -2.5 -2.0 -1.2

adams中函数用法

Adams常用函数 step可能是最常用的: step(time,0,0,1,50)+ step(time,4,0,6,-100)+ step(tme,9,0,10,50) 函数原形STEP(A,x1,h1,x2,h2) 解释:由数组A的x值,生成区间(x1,h1)至(x2,h2)之间的阶梯曲线,返回y值的数据。 举个常用的例子。 比如STEP(time,1,0,2,100) time在adams中是个递增的变量,相当于一个数组。那么step的返回值就是随着time变化的值。 这个例子将表示在time从(1,2)的过程中,返回值将从0,100。看看例子,两个小球,一个使用step 函数设置了位移,另外一个是参考。当然,这个变化过程,adams使用了缓和的图形,从其位移图中可以看出来。step既然是个返回值,就可以使用加减法了。如上例,如果设置下面的小球的位移如下:STEP(time,1,0,2,100)+step(time,2,0,3,400)+step(time,3,0,4,-200) 1.以前用过碰撞函数,有单向和双向函数的区分,其中系统的球面等碰撞为其特例! IMPACT (Displacement Variable, Veloci t y Variable, Trigger for Displacement Variable, Stiffness Coefficient, Stiffness Force Exponent, Damping Coefficient, Damping Ramp-up Distance) BISTOP (Displacement Variable, Velocity Variable, Low Trigger for Displacement Variable, High Trigger for Displacement Variable, Stiffness Coefficient, Stiffness Force Exponent, Damping Coefficient, Damping Ramp-up Distance) 2.if函数 这个函数最好不要使用,他的使用会带来突变,会使运算的时候不收敛。不过应急的时候还是可以一用。 if(time-1:1,0,if(time-2:0,-1,-1)) IF(Expression1: Expression2, Expression3, Expression4) adams要计算Expression1的值: 如果他的值小于0,则执行Expression2语句,如果Expression1的值等于0,则执行Expression3语句,如果Expression1的值大于0,则执行Expression4语句 我得if语句的意思是:如果时间小于1的时候,加速度为1,如果时间为1,加速度为0,如果时间大于1小于2,则加速度为0,如果时间大于、等于2则,加速度为-1 4. 我得一个想法 就是利用sign函数构造 比较常用的是给机构加上一个与运动方向相反的作用力等等可以先测量施加力对象的运动速度,然后利用速度的变化,插入measure到sign函数里面就可以获得与运动方向相反的作用力

adams初级设置教程

1、ADAMS中的单位的问题 开始的时候需要为模型设置单位。在所有的预置单位系统中,时间单位是秒,角度是度。可设置: MMKS--设置长度为千米,质量为千克,力为牛顿。 MKS—设置长度为米,质量为千克,力为牛顿。 CGS—设置长度为厘米,质量为克,力为达因。 IPS—设置长度为英寸,质量为斯勒格(slug),力为磅。 2、如何永久改变ADAMS的启动路径? 在ADAMS启动后,每次更改路径很费时,我们习惯将自己的文件存在某一文件夹下;事实上,在Adams的快捷方式上右击鼠标,选属性,再在起始位置上输入你想要得路径就可以了。 3、关于ADAMS的坐标系的问题。 当第一次启动ADAMs/View时,在窗口的左下角显示了一个三视坐标轴。该坐标轴为模型数据库的全局坐标系。缺省情况下,ADAMS/View用笛卡儿坐标系作为全局坐标系。ADAMS/View将全局坐标系固定在地面上。 当创建零件时,ADAMS/View给每个零件分配一个坐标系,也就是局部坐标系。零件的局部坐标系随着零件一起移动。局部坐标系可以方便地定义物体的位 置,ADAMS/View也可返回如零件的位置——零件局部坐标系相对于全局坐标系 的位移的仿真结果。局部坐标系使得对物体上的几何体和点的描述比较方便。物体坐标系不太容易理解。你可以自己建一个part,通过移动它的位置来体会。 4、关于物体的位置和方向的修改 可以有两种途径修改物体的位置和方向,一种是修改物体的局部坐标系的位置,也就是通过MODIFY物体的position属性;令一种方法就是修改物体在局部坐标系中的位置,可以通过修改控制物体的关键点来实现。我感觉这两种方法的结果是不同的,但是对于仿真过程来说,物体的位置就是质心的位置,所以对于仿真是一样的。

adams函数

adams 函数 ADAMS/View 运行函数及ADAMS/Solver 函数 2008-04-18 04:54 3 ADAMS/View 运行函数及ADAMS/Solver 函数 ADAMS/View 运行函数能够表明定义系统行为的仿真状态间的数学关系。在ADAMS/ View 中将这些运行函数与其他不同元素一同创建各种系统变量,这些函数大多数都以施加 力和产生运动为目的。之后在仿真中进行解算时,ADAMS/ Solver 会用到这些变量函数并 进行计算更新,在仿真过程中这些系统状态会发生改变,如随时间的改变而改变、随零件 的移动而改变、施加的力以不同方式改变等。 3.1 位移函数 (1)线位移函数 DX 返回位移矢量在坐标系X 轴方向的分量 DY 返回位移矢量在坐标系Y 轴方向的分量 DZ 返回位移矢量在坐标系Z 轴方向的分量 DM 返回位移距离 (2)角位移函数 AX 返回一指定标架绕另一标架X 轴旋转的角度 AY 返回一指定标架绕另一标架Y 轴旋转的角度 AZ 返回一指定标架绕另一标架Z 轴旋转的角度 (3)按313 顺序的角位移 PSI 按照313 旋转顺序,返回指定坐标系相对于参考坐标系的第一旋转角度 THETA 按照313 旋转顺序,返回指定坐标系相对于参考坐标系的第二旋转角度 PHI 按照313 旋转系列,返回指定坐标系相对于参考坐标系的第三旋转角度 (4)按照321 顺序的角位移 YAW 按照321 旋转顺序,返回指定坐标系相对于参考坐标系的第一旋转角度 PITCH 按照321 旋转顺序,返回指定坐标系相对于参考坐标系的第二旋转角度的相 反数 ROLL 按照321 旋转顺序,返回指定坐标系相对于参考坐标系的第三旋转角度 3.2 速度函数 (1)线速度函数 VX 返回两标架相对于指定坐标系的速度矢量差在X 轴的分量 VY 返回两标架相对于指定坐标系的速度矢量差在Y 轴的分量 VZ 返回两标架相对于指定坐标系的速度矢量差在Z 轴的分量 VM 返回两标架相对于指定坐标系的速度矢量差的幅值 VR 返回两标架的径向相对速度 (2)角速度函数 WX 返回两标架的角速度矢量差在X 轴的分量

ADAMS函数使用精华

样条差值函数 Akima Fitting Method(AKISPL) 定义:由曲线或者曲面返回曲线的导数或者曲线的拟合值。通过Akima样条曲线拟合方法,使用一系列离散点来拟合曲线。 格式:AKISPL(第一独立变量,第二独立变量,样条函数名,求导阶数) 自变量:第一独立变量(必须)--代表样条中第一独立变量的实数变量。 第二独立变量(必须)-- 代表样条中第二独立变量的实数变量。 样条函数名字(必须)—已存在的数据样条实体的名字,定义了用作拟合的一系列离散点。 求导阶树(可选)—在求离散点时用作求导的阶树。 其合法值为: *0—返回曲线坐标值。 *1—返回一阶导数值。 *2—返回二阶导数值。 注意:当拟合曲面时,不必指明Derivative Order(求导阶数)。 例子:某样条曲线,spline_1,其定义的离散点如下表所示。使用Akima样条拟合方法将这些离散点生成拟合函数。 既然样条曲线定义的是曲线而不是曲面, 因此, 将Second Independent Variable(第二独立变量)设置为零。 在下列例子中,给出了独立变量的值和数据,AKISPL返回拟合值: f = AKISPL(DX(marker_1, marker_2, marker_2), 0, spline_1) 由以上拟合点生成的样条曲线如下图所示:

CURVE 定义:CURVE 函数定义了一条B 样条曲线或者以CURVE 声明创建的用户自定义曲线。 格式: CURVE (alpha, iord, comp, id) 自变量:alpha —确定独立变量α的值的实变量,其中CURVE 函数计算曲线。如果曲线是以CURVE 计算的B 样条曲 线, α的取值范围为11-≤≤α。如果曲线是通过CURSUB 计算得出,alpha 的去值范围为MAXPAR MINPAR ≤≤α。 Iord —定义CURVE 函数中求导阶树的整数值。其合法值为 *0—返回曲线坐标。 *1—返回一阶偏导。 *2—返回二阶偏导。 Comp —定义CURVE 函数中分量的整数变量。其合法值为: *1—返回x 坐标值或者其导数值。 *2—返回y 坐标值或者其导数值。 *3—返回z 坐标值或者其导数值。 自变量iord 和icomp 组合在一起可以让你获得下面九个值的任何一个: Id —定义CURVE 中标志符的整数变量。

adams个别问题总结

Adams个别问题总结 1、如何永久改变ADAMS的启动路径 在ADAMS启动后,每次更改路径很费时,我们习惯将自己的文件存在某一文件夹下;事实上,在Adams的快捷方式上右击鼠标,选属性,再在起始位置上输入你想要得路径就可以了。 2、ADAMS中的单位的问题 开始的时候需要为模型设置单位。在所有的预置单位系统中,时间单位是秒,角度是度。可设置: MMKS--设置长度为千米,质量为千克,力为牛顿。 MKS—设置长度为米,质量为千克,力为牛顿。 CGS—设置长度为厘米,质量为克,力为达因。 IPS—设置长度为英寸,质量为斯勒格(slug),力为磅。 在模型运行的过程中也可以改变单位系统的设定。还可以在文本框中使用自己的单位,比如默认的角度单位度时可以使用R表示弧度。我感觉在ADAMS 内部好像是把所有的带单位的输入量都转换成统一的单位了。 3、关于ADAMS的坐标系的问题。 当第一次启动ADAMs/View时,在窗口的左下角显示了一个三视坐标轴。该坐标轴为模型数据库的全局坐标系。缺省情况下,ADAMS/View用笛卡儿坐标系作为全局坐标系。ADAMS/View将全局坐标系固定在地面上。 当创建零件时,ADAMS/View给每个零件分配一个坐标系,也就是局部坐标系。零件的局部坐标系随着零件一起移动。局部坐标系可以方便地定义物体的位置,ADAMS/View也可返回如零件的位置——零件局部坐标系相对于全局坐标系的位移的仿真结果。局部坐标系使得对物体上的几何体和点的描述比较方便。物 体坐标系不太容易理解。你可以自己建一个part,通过移动它的位置来体会。4、关于物体的位置和方向的修改 可以有两种途径修改物体的位置和方向,一种是修改物体的局部坐标系的位置,也就是通过modify物体的position属性;令一种方法就是修改物体在局部坐标系中的位置,可以通过修改控制物体的关键点来实现。我感觉这两种方法的结果是不同的,但是对于仿真过程来说,物体的位置就是质心的位置,所以对于仿真是一样的。 5、关于ADAMS中方向的描述。 对于初学的人来说,方向的描述不太容易理解。之前我们都是用方向余弦之类的量来描述方向的。在ADAMS中,为了求解方程是计算的方便,使用欧拉角来描述方向。就是用绕坐标轴转过的角度来定义。旋转的旋转轴可以自己定义,默认使用313,也就是先绕z轴,再绕x轴,再绕z轴。 6、Marker点与Pointer点区别

(完整版)ADAMS常用函数的说明

一、几个常用函数的说明 1、 STEP函数 格式:STEP (x, x0, h0, x1, h1) 参数说明: x ―自变量,可以是时间或时间的任一函数 x0 ―自变量的STEP函数开始值,可以是常数或函数表达式或设计变量; x1 ―自变量的STEP函数结束值,可以是常数、函数表达式或设计变量; h0 ― STEP函数的初始值,可以是常数、设计变量或其它函数表达式; h1 ― STEP函数的最终值,可以是常数、设计变量或其它函数表达式。 2、 IF函数 格式:IF(表达式1: 表达式2, 表达式3, 表达式4) 参数说明: 表达式1-ADAMS的评估表达式; 表达式2-如果的Expression1值小于0,IF函数返回的Expression2值; 表达式3-如果表达式1的值等于0,IF函数返回表达式3的值; 表达式4-如果表达式1的值大于0,IF函数返回表达式4的值; 例如:函数IF(time-2.5:0,0.5,1)

结果:0.0 if time < 2.5 0.5 if time = 2.5 1.0 if time > 2.5 3、AKISPL函数 格式:AKISPL (First Independent Variable, Second Independent Variable,Spline Name, Derivati ve Order) 参数说明: First Independent Variable ——spline中的第一个自变量 Second Independent Variable(可选) ——spline中的第二自变量 Spline Name ——数据单元spline的名称 Derivative Order(可选) ——插值点的微分阶数,一般用0就可以了 例如: function = AKISPL(DX(marker_1, marker_2), 0, spline_1) spline_1用下表中的离散数据定义:

ADAMS软件中IMPACT函数参数的确定(精)

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式(3-12)可以写成 n n F k D δδ =+ (3-16) 其中D 为该式中的阻尼参数,δ 为两物体接触时的相对移动速度。Hund 与 Grossley [83]曾提出确定D 的方法: n D μδ= (3-17) 在式(3-17)中μ被称为滞后阻尼因子。在碰撞非线性弹簧阻尼模型中,碰撞过程会导致能量的损失,这是由碰撞的阻尼项造成的。图3-4表示在碰撞过程中碰撞 力的变化: 在该图中()t -表示开始碰撞前的那一时刻, ()m t 表示碰撞达到最大穿透量的那一时刻,()t +表示开始碰撞结束后两物体分离的那一时刻。在式(3-17)中阻尼系数D 或 滞后阻尼因子μ需要确定。应用经典的冲量定理与能量守恒原理可以确定以上两个变量。 根据能量守恒定理可知在碰撞前与碰撞后两物体的动能损失可以用恢复系 数e 与两物体间的相对速度()δ - 来表示 其中()()()i j V V δ---=- (()i V -表示物体i 碰撞接触前的速度,()j V - 表示物体j 碰撞接触前的速度) 图3-4 碰撞力的变化

ADAMS函数使用精华

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ADAMS中step函数的用法

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Adams常用函数介绍

常数函数 常用的常数函数(constant):PI圆周率;RTOD弧度转化为度数时的乘积系数,值为180/PI;DTOR度数转化为弧度时的乘积系数,值为PI/ 180。 运动副的驱动函数 function:30.0d*time,type:displacement和function:30.0d,type:velocity 作用是一样的,它们都表示角速度为30.0。同样,function:30.0d*time,type:velocity和function:30.0d,type:acceleration作用也是一样的,它们都表示角加速度为30.0。一般应优先使用function:30.0d,type:velocity这种表示法,它更简单,更便于理解。 function:5,type:acceleration,表示物体的加速度为常数5;function:STEP( time , 0 , 0 , 5 , 25 ),type:velocity,表示物体的速度从(0,0)变化为(5,25),物体的加速度并不是一个常数,加速度的图形是一条先增后减的弧线。在定义驱动函数时,如果已知物体的加速度为5,则应采用第一个表达式;如果不知道加速度的变化规律,只知道速度由0,0)变化为(5,25),则应采用第二个表达式。 d是degree度数的简写,在此d并不是单位,而是用来区分滑移运动和旋转运动,代表旋转。旋转副的驱动函数中函数值后必须加d,如STEP( time , 0 , 0d , 3 , 300d ),而滑移副的驱动函数中函数值后不能加d。则直接数字,默认单位。 常用的驱动函数STEP 格式:STEP (x, x0, h0, x1, h1) 参数说明: x ―自变量,可以是时间或时间的任一函数; x0 ―自变量的STEP函数开始值; x1 ―自变量的STEP函数结束值; h0 ―当前时间点相对于上一时间点的函数值增量; h1 ―当前时间点相对于上一时间点的函数值增量。 例:旋转运动副的驱动函数(function)为STEP( time , 0 , 0d , 3 , 300d )+STEP( time , 3 , 0d , 6 , 0d )+STEP( time , 6 , 0d , 9 , -300d ),函数值(type)为velocity,STEP( time , 3 , 0d , 6 , 0d )可省略。驱动函数表示物体在0-3s做加速运动,速度由0 d变为300d,物体在3-6s做匀速运动,速度不变,物体在6-9s

Adams中的命令

ADAMS常用函数总结! 在使用adams的过程中,由于函数比较多,大概有11种之多,如 1、Displacement Function 2、Velocity Functions 3、 Acceleration Functions 4、 Contact Functions 5、 Spline Functions 6、 Force in Object Functions 7、Resultant Force Functions 8、 Math Functions 9、 Data Element Access 10、User-Written Subroutine Invocation 11、Constants & Variables。 在adams中也有帮助文档,但是对于初学者来说还是有一定的难度的,基于这种情况我总结了一下几种常用的函数,希望能够起到抛砖引玉的作用! 1、 STEP函数 格式:STEP (x, x0, h0, x1, h1) 参数说明: x ―自变量,可以是时间或时间的任一函数 x0 ―自变量的STEP函数开始值,可以是常数或函数表达式或设计变量; x1 ―自变量的STEP函数结束值,可以是常数、函数表达式或设计变量 h0 ― STEP函数的初始值,可以是常数、设计变量或其它函数表达式 h1 ― STEP函数的最终值,可以是常数、设计变量或其它函数表达式 2、 IF函数 格式:IF(表达式1: 表达式2, 表达式3, 表达式4) 参数说明: 表达式1-ADAMS的评估表达式; 表达式2-如果的Expression1值小于0,IF函数返回的Expression2值; 表达式3-如果表达式1的值等于0,IF函数返回表达式3的值; 表达式4-如果表达式1的值大于0,IF函数返回表达式4的值; 例如:函数 IF(time-2.5:0,0.5,1) 结果: 0.0 if time < 2.5 0.5 if time = 2.5 1.0 if time > 2.5 MSC.ADAMS 中IF语的写法和含义 □基本粒子发表于 2005-7-6 20:52:00 IF 语句的形式是这样的 IF(表达式1:表达式2,表达式3,表达式4) 如果表达式1的值小于0 执行表达式2 如果表达式1的值等于0 执行表达式3 如果表达式1的值大于0 执行表达式4 所以你的函数可以写为 IF(time-8:你的表达式,你的表达式,0)就可以了

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