On the erodibility of fine grained sediments in an infilling freshwater system

اختصاصی از یارا فایل On the erodibility of fine grained sediments in an infilling freshwater system دانلود با لینک مستقیم و پرسرعت .

On the erodibility of fine-grained sediments in an infilling freshwater system

T.J. Andersen a, E. J. Houwing b & M. Pejrup ~
aInstitute of Geography, University of Copenhagen, Oster Voldgade 10, DK-1350 K~benhavn
K, Denmark.
bInstitute for Inland Water Management and Waste Water Treatment (RIZA), Rijkswaterstaat,
van Leeuwenhoekweg 20, 3316 AV Dordrecht, The Netherlands

The erodibility of fine-grained sediments from the Hollandsch Diep freshwater system has been
measured using a portable EROMES system. The erosion experiments were carried out on natural
sediment surfaces sampled with a box-corer. The measured erosion thresholds varied between
0.16 and 0.70 N m 2. The erosion thresholds were positively correlated to the dry density of the
bed material (r 2 = 0.33) whereas no significant dependence was found on either grain size, organic
content or chlorophyll a content. The measured erosion rates varied between 0.04 and 1.68 g m -2
s -1 and a strong positive correlation with bed shear stress was observed. The equivalent settling
diameters of the eroded material were generally 5 to 10 times larger than that of the primary
particles which shows that the material was eroded as aggregates. However, a strong positive
correlation between the two settling diameters (r z = 0.74) also indicates that the coarser modes
of the primary grain size distributions affect size or density of the faster settling aggregates. The
lack of correlation between the erodibility and organic content and chlorophyll a content indicates
that microphytobenthos is not significantly modifying the erodibility of the sediments at the study
sites. The macrofaunal community is also poorly developed with few species and small numbers
of individuals and it is concluded that the erodibility is mainly controlled by accumulation rate,
dry density of the bed material and perhaps maximum current velocity at the sites. This is further
supported by the similarity with earlier measurements carried out on settled beds in laboratories.
Keywords: Erosion threshold, erosion rate, sediment settling, Hollandsch Diep, The Netherlands

چکیده:

افزایش تجمع رسوبات ریز دانه در رودخانه ‏های جاری در دشت‏ های انگلستان به دلیل تغییرات کاربری اراضی

بررسی فرسایش ‏پذیری رسوبات ریز دانه

بررسی توزیع مکانی و زمانی فرسایش ‏پذیری رسوبات ریزدانه

بررسی ویژگی‏های مؤثر رسوب بر فرسایش ‏پذیری رسوبات

توجه:

فایل ترجمه شده بصورت پاورپوینت آماده ارائه می باشد.

دانلود پایان نامه دکترای زبان انگلیسی AN INVESTIGATION INTO THE USE OF ARGUMENT STRUCTURE AND LEXICAL MAPPING THEORY FOR MACHIN

اختصاصی از یارا فایل دانلود پایان نامه دکترای زبان انگلیسی AN INVESTIGATION INTO THE USE OF ARGUMENT STRUCTURE AND LEXICAL MAPPING THEORY FOR MACHINE TRANSLATION دانلود با لینک مستقیم و پرسرعت .

دانلود پایان نامه دکترای زبان انگلیسی AN INVESTIGATION INTO THE USE OF ARGUMENT STRUCTURE AND LEXICAL MAPPING THEORY FOR MACHINE TRANSLATION که شامل 167 صفحه و بشرح زیر میباشد:

نوع فایل : PDF قابل ویرایش

AN INVESTIGATION INTO THE USE OF ARGUMENT STRUCTURE AND LEXICAL MAPPING THEORY FOR MACHINE TRANSLATION
Abstract
In recent work on the Lexical-Functional Grammar (LFG) formalism, argument
structure (a-structure) and lexical mapping theory have been used to explain many
linguistic behaviours across languages. It has been suggested that the combination
of c-structure, f-structure and a-structure might form a suitable architecture
for Universal Grammar. If this suggestion is valid, the LFG formalism would be a
suitable linguistic model for Machine Translation (MT). This thesis reports on the
investigations carried out on using a-structure and lexical mapping theory for aiding
various sub-tasks in MT. The two investigations described in this thesis are the
abilities of a-structure and lexical mapping theory to: (1) aid different kinds of lexical
and structural disambiguations involving verbs and prepositions, and (2) act
as a suitable medium for carrying out source-to-target language transfer. Based
on the results of these investigations, this thesis also gives an evaluation of how
well a-structure and lexical mapping theory can improve the existing models of
linguistic-based MT.

Contents
1 Introduction 1
1.1 Problems of Machine Translation ... 3
1.1.1 Why are problems in MT vital to the application of real-life MT systems? 3
1.1.2 What makes MT so difficult? .... 4
1.1.3 Linguistic Problems ....5
1.1.4 Meaning Representation .... 7
1.2 Motivation and Aims of the Research ...8
1.3 Organisation of this Thesis ... 10
2 Machine Translation 12
2.1 Different Kinds of Ambiguities .... 13
2.1.1 Lexical Ambiguity ... 13
2.1.2 Structural Ambiguity ....14
2.2 Different Kinds of MT Systems .... 15
2.2.1 Direct MT systems ... 15
2.2.2 Indirect MT Systems ....16
2.3 Practical Use of some MT Systems ..... 18
2.3.1 Systran ..... 18
2.3.2 M´et´eo ..... 20
2.3.3 Discussion ...21
2.4 Methods of Transfer ..... 22
2.5 Alternative Approaches to Machine Translation .... 24
2.5.1 Sublanguage Approach .... 25
2.5.2 Statistics-based Approach ... 27
2.5.3 Example-based Approach ... 28
2.6 Conclusion .....29
3 Lexical-Functional Grammar (LFG) 32
3.1 The LFG Formalism ..... 33
3.1.1 Constituent Structure (c-structure) ... 34
3.1.2 Functional Structure (f-structure) ... 35
3.1.3 Semantic Structure (s-structure) ...41
3.2 Lexical-Functional Grammar in Machine Translation ... 43
3.2.1 Kudo and Nomura’s Lexical-Functional Transfer .... 44
3.2.2 Kaplan et al.’s approach to MT ...45
3.2.3 Her et al.’s Lexical and Idiomatic Transfer .... 47
3.3 Conclusion .....51
4 Argument Structure and Lexical Mapping Theory 54
4.1 Thematic Roles .... 55
4.1.1 Agent ..... 56
4.1.2 Beneficiary, Recipient and Experiencer ..... 57
4.1.3 Instrument ...61
4.1.4 Theme and Patient ... 61
4.1.5 Locative .... 64
4.2 Argument Structure ..... 66
4.2.1 How to establish the a-structure(s) for a verb? ..67
4.3 Lexical Mapping Theory .... 69
4.3.1 Thematic Hierarchy ....69
4.3.2 Classification of Syntactic Functions .. 70
4.3.3 Lexical Mapping Principles ..... 71
4.3.4 Well-formedness Conditions .... 76
4.4 Lexical Mapping— A Demonstration ...76
4.4.1 With the Verb ‘give’ ....76
4.4.2 With the Morpholexical Operation ‘passive’ ... 78
4.4.3 With the Morpholexical Operation ‘applicative’ .... 78
4.5 Is A-structure another variant of Case Grammar? .... 79
4.5.1 Case Grammar .... 80
4.5.2 A-structure and Case Grammar — A Comparison ...81
4.6 Conclusion .....83
5 Using A-structure and Lexical Mapping Theory for MT 84
5.1 Parsing Source Language Sentence ..... 84
5.1.1 Differentiating V + PP from Phrasal Verb + NP ..86
5.1.2 Differentiating NP with N and PP from NP + PP .... 92
5.2 Lexical Selection .... 96
5.2.1 Lexical Selection for Ergative Verbs .. 98
5.2.2 Lexical Selection for Verbs ... 101
5.2.3 Lexical Selection for Phrasal Verbs ... 106
5.3 Aiding Sentence Generation ....108
5.3.1 Verb Copying in Chinese ... 109
5.3.2 Positioning PPs within a Chinese Sentence .... 111
5.4 Discussion .....114
5.5 Conclusion .....117
6 Dealing with the Transfer of Passive Sentences 119
6.1 Using F-structure as a medium for Transfer .. 119
6.2 Passive in English ...122
6.3 Passive in Chinese ..... 126
6.4 Differences between Passive Sentences in English and in Chinese ... 129
6.5 The Transfer from English passive sentences to Chinese .... 133
6.6 Discussion .....136
6.7 Conclusion .....140
7 Conclusion and FutureWork 141
7.1 Problems in Using A-structure and Lexical Mapping Theory inMT .... 141
7.1.1 No Matching Source-and-Target Language A-structures ...142
7.1.2 Difficulty in Establishing Appropriate A-structures ... 144
7.2 What makes this investigation successful? ... 147
7.3 FutureWork ..... 148
7.3.1 Disambiguating nouns .... 149
7.3.2 Automatic extraction of a-structures from a corpus ... 150
7.3.3 Reducing the processing time .... 150
7.4 Conclusion .....151

List of Figures
1.1 A Word-for-Word Translation .... 4
2.1 Typical building blocks of a transfer-based MT system ..17
2.2 Building blocks of an interlingual MT system ..... 17
2.3 Building blocks of a multilingual MT system using the interlingual approach .. 18
2.4 A dictionary entry for transferring ‘bug’ suggested by Her et al. (1994) .... 26
3.1 C-structure for the sentence “John played Mary a tune on the violin.” ... 34
3.2 F-structure for the sentence “John tried to play the guitar.” .... 36
3.3 F-structure for the sentence “John played Mary a tune on the violin.” ... 38
3.4 C-structure and F-structure for the sentence “John died.” .... 41
3.5 C-structure & F-structure correspondence of the sentence “John died.” .. 42
3.6 S-structure for the sentence “The baby fell.” ... 42
3.7 C-structure, F-structure and S-structure correspondence of the sentence “John died.” 44
3.8 The correspondences between different structures for source and target languages inLFG ....... 46
3.9 A minimal f-structure for transferring the idiom “to kick the bucket” suggested by Her et al. (1994) ..... 50
5.1 Two potential c-structures for the word sequence “John played on words” ... 85
5.2 F-structure for “John played on words.” ... 89
5.3 F-structure for “John played on the table.” ... 89
5.4 The lexical mapping between a-structure arguments and their corresponding syntactic functions for the sentences in Table 5.1 .... 92
5.5 A possible c-structure for “John bought a book in a bookshop in Prague.” produced
by a syntax-based parser.... 93
5.6 Another possible c-structure for “John bought a book in a bookshop in Prague.” produced by a parser.... 94
5.7 The c-structure for “John saw a girl with a dog with a telescope.” ... 96
5.8 Examples of English ergative verbs with matching Chinese counterpart ... 99
5.9 Examples of English ergative verbs with different Chinese translation in transitive and intransitive cases ... 100
5.10 A-structures and sample sentences for the English verb ‘tell’ and its Chinese counterparts ..... 102
5.11 The use of a-structures for lexical selection .. 103
5.12 Some examples on lexical selection for verbs by using a-structures ... 105
6.1 English and Chinese F-structures for “Mary was killed by John.”...130
6.2 English and Chinese F-structures for “Mary was killed.”.... 131
6.3 The English and Chinese equivalents of the sentence “Mary was given a book by John” .... 132
6.4 Skeleton of Chinese F-structure for “Mary was given a book by John.”.. 135
6.5 The final Chinese F-structure for “Mary was given a book by John.”... 136
6.6 Transferring English passive sentence into Chinese using a-structure and lexical
mapping theory .... 137

List of Tables
1.1 Different meanings of some nouns ..... 7
3.1 Different cases for the Czech proper noun ‘Jan’ ....40
5.1 Some examples of different combinations of verbs and prepositions ... 88
5.2 Different Meanings of ‘look up’ .... 107
5.3 The a-structure arguments for ‘look up’ and its Chinese equivalents ... 108

پاور پوینت جدید آموزش کاربرد حروف تعریف a ,an ,the در زبان انگلیسی

اختصاصی از یارا فایل پاور پوینت جدید آموزش کاربرد حروف تعریف a ,an ,the در زبان انگلیسی دانلود با لینک مستقیم و پرسرعت .

قابل توجه مدرسان زبان و دانش آموزان گرامی

همانطور که می دانید براساس تحقیقات انجام شده ،روش های نوین تدریس اعم از روش مستقیم ،گرامر ترجمه ،ارتباطی و...هیچکدام به تنهایی روش کامل آموزش زبان به شمار نمی روند وتنها روش برتر استفاده از روش گلچین (Eclectic Method) می باشد که عبارت از استفاده بهینه از مزایای تمام روشها ی آموزش زبان ،چرا که دانش آموزان با توجه به تفاوتهای فردی نیازهای ویژه ای دارند که پاورپوینت حاضر براساس همین نظریه واستفاده از مزایای روش گرامر ترجمه با تلفیق روش روان شناختی فعال سازی نیمکره راست مغز طراحی شده است.در بحث آموزش زبان فرض براین است که زبان آموزی در نیمکره چپ مغز پردازش می شود حال اگر با استفاده از موزیک وتصویر نیمکره راست مغز فراگیران رانیز فعال کنیم کمک زیادی به درک آگاهانه ساختار دستوری زبان انگلیسی توسط یاد گیرنده خواهیم کرد.

مزایا:

 قابل استفاده  برای دانش آموزان ،معلمان ودانشجویان گرامی

• قابل نمایش در کلاسها توسط دستگاه پروژکتور با قابلیت اضافه کردن مطالب جدید
• طراحی جدید  ومطالب متنوع توسط کارشناس ارشد آموزش زبان انگلیسی درتاریخ 20/11/94
  
• امکان درک آکاهانه ساختار دستوری گرامر پایه توسط فراگیران

 روش استفاده:

ا- پاورپوینت مورد نظر را دانلود کرده ودر کامپیوتر خود ذخیره فرمایید.

2-مطالب گرامری نوشته شده را مطالعه کنید ، مطالب این قسمت بیشتر برای دانش آموزان دوره های اول و دوم متوسطه طراحی شده است ولی شما می توانید برحسب نیاز فراگیران در هرکلاسی استفاده کنید.

3-دانش آموزان  ازمطالب  گرامری به شدت استقبال خواهند کرد وبرای کمک به تقویت  حافظه  فوق العاده موثر است .

4-شما می توانید پاور پوینت را در فلش خود ذخیره ودر کلاسهای مختلف استفاده کنید .

5-پاورپوینت طوری طراحی شده که می توانید مطالب مورد نیاز خود را اضافه ویا مواردی را حذف نمایید.

6-مطالب طرح درس خود را در قسمت های مختلف بگنجانید وهر جا لازم شد به جای استفاده از وایت برد وتخته سیاه از پاور پوینت وفلش خود استفاده کنید.بدین ترتیب در وقت وانرژی خود تا حد زیادی صرفه جویی خواهید کرد.

این ppt را
جایی ندیده اید

  مورد تایید گروههای آموزش زبان انگلیسی EEG

Learning English is easy,just try and enjoy it »

همین حالا...

ppt موزیکال        حجم فایل: MB 2.76                           نوع فایل :  zip