研究生: |
王立民 Wang, Li-Min. |
---|---|
論文名稱: |
扭轉圓筒的摺痕與幾何機制 Geometric Mechanism of Crease Formation on Twisting Cylindrical Shell |
指導教授: |
洪在明
Hong, Tzay-Ming |
口試委員: |
陳宣毅
CHEN, Hsuan-Yi 欒丕綱 Luan, Pi-Gang 王道維 Wang, Daw-Wei 周亞謙 Chou, Ya-Chang |
學位類別: |
碩士 Master |
系所名稱: |
理學院 - 物理學系 Department of Physics |
論文出版年: | 2018 |
畢業學年度: | 106 |
語文別: | 中文 |
論文頁數: | 112 |
中文關鍵詞: | 摺痕 、扭轉 、彈塑性力學 、摺紙 、斷詞 、語言學 |
外文關鍵詞: | crease, twisting, origami, Föppl–von Kármán equations, text segmentation, linguistics |
相關次數: | 點閱:2 下載:0 |
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本論文包含了兩個工作:(一)扭轉圓筒的摺痕與幾何機制(二)語言統計學的縮
放結構。兩者皆是跨領域的研究,前者包含了摺紙數學還有彈塑性力學,後者涉及
統計學、語言學、自然語言處理與物理。
論文的第一部分,討論在不同幾何限制下,薄膜圓筒被扭轉時因挫屈(buckling)
產生的規律摺痕。發現圓筒上的摺痕數量N只要透過半徑R與寬度w的比例
就能被唯一決定,即N = N(R/w),是一個無關厚度的二維參數。從簡單的幾何關
係、能量最小化與一對可以直接描述摺痕形成的新材料參數,我們理論推導出的解
析解,可以成功擬合實驗事實,在摺痕力學的描述上比舊有的彈塑性力學參數表
現更加簡單。除了摺痕數量,R/w還能用來描述摺痕的型態:斷裂摺痕、規律摺痕
與不規律摺痕三種型態。本文還會探討如何從這一簡單、可解析的結果出發,建
立一座串聯小形變與大形變問題的橋樑,不需要透過複雜的von Kármán–Donnell
equations求數值解。除了最簡單的圓筒,我們還將問題拓展到截錐、多邊形管、
斜切管、圓球等不同幾何結構,試圖在材料和幾何上統一這類問題。根據尺度縮放
不影響摺痕形態的這一特性,我們將此結果應用在解釋地球板塊裂痕與山脈形成的
機制上,提出因扭轉產生板塊形變的機制。
論文的第二部分,延續了前任學長蔡孟學在詞(word)頻和字/音節(character/
syllable)頻排名的統計關係研究,深入探討「縮放結構」(scaling structure)
的來源:將詞的出現次數排名x與其組成字的出現次數排名y畫成y x圖,會
得到一層一層、階梯狀的規律結構。此一結構在不同的自然語言文本中皆會出現,
無關文本的類型與語言,而且和語言統計學中知名的齊夫法則(Zipf’s law),
即單詞的出現次數N會和其次數排名x成反比,是互補的定律。也就是說,這一定
律可以獨立於Zipf’s law出現。我們進一步發現描述這一結構完整度的指標:SP
vaule、搭配函數(Collocation function)以及連結函數(Link function),可以
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用來判斷切詞(word segmentation)的準確度,而不需依賴大量數據或者對該語
言的先備知識。我們根據此結果提出一個新演算法來切詞,並且可以藉由自我評分
來改善切詞的能力。因為這一新演算法具有不需要先備知識的特性,它可以被用來
研究未知語言與語料庫不夠完整的語言,比如動物語言和嬰兒語言,或者更進一步
用來研究一個領域的統計結構與統計單位組成。此外,我們還透過人造文本來研究
縮放結構產生與破壞的機制,證明這一結構並非路邊隨便找來的文本就有,而是具
有特定、待更深入研究的統計意義。
This thesis contain two work: 1. Geometric Mechanism of Crease Formation on
Twisting Cylindrical Shell, and 2. Scaling Pattern: A Fundamental Structure in
Statistical Linguistics. Both of them are interdisciplinary research. The former
contain mathematics of paper folding and elastic-plastic mechanics, the latter
involved statistics, linguistics, natural language processing and physics.
The first part of thesis discuss the mechanism of regular creases’ pattern
formation due to twisting buckling under different geometry constraints. Discovering
the numbr of creases N can unique determined by the ratio of radius
R and width w of cylindrical shell, a 2D parameter, N = N(R/w). We get analytic
solutions that fits the experimental data from simple geometry, energy
minimization and two new material properties. These new properties display
more concise than ordinary material properties used in elastic-plastic mechanics.
In addition to N, R/w can be used to depict three types of creases: fracture,
regular and irregular. This thesis also allow us to build a bridge between
small and large deformation problem form simple and analytic results instead
of numerical solutions of von Kármán–Donnell equations which are complicated.
Beside the simplest case, cylindrical shell, we extend this problem to
truncated cone, polygon cylindrical shell, beveled end pipe and ball, trying to
unify the influence of material and geometry. According to the scaling property
of types of creases, we apply the result to explain of creases of earth’s plates,
the formation of mountains, and propose the twisting buckling mechanism of
deformation of earth’s plates.
The second part of this thesis continues, the work of Meng-Xue Tsai in our
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lab, the reaserch of statistical relationship between frequency rank of words
and that of characters/syllables and investigate the origin of “scaling structure”:
ploting word rank x and character/syllables ranky, you will get a stepped
layer structure. This structure shown in different natrual language corpus, writing
styles and languages. That is to say, we discover a stastistics law which is
complementary to Zipf’s law. Furthermore we describe the completeness of
scaling structure with three quantities: SP vaule, Collocation function and Link
function. These index can be used to judge accuracy of word segmentation,
and does not dependent on large data or prior knowledge of the language.
We popose a new word segmentation algorithm which can improve its ability
by self-scoring mechanism, Due to its feature, this algorithm can be applied to
unknown language or language with small data base such as animal language
or baby language, or finding out the basic statistics unit and structure in a field.
On top of that, by finding out conditions ruining scaling structure, we prove this
structure is not arbitrary , but has statistically significant.
Bibliography
[1] 李致宇。明「摺」「寶」身—從摺痕研究改良寶特瓶、鐵鋁罐回收的安全
性。第十六屆旺宏科學獎,物理SA16-138 (2017)
[2] 摺友會。關於濕摺法。Retrieved from Hkgyou.com
http://www.hkgyou.com/index.php/2012-03-30-15-14-49/
19-2012-04-03-13-48-34
[3] N. Yamaki, and K. Otomo. Experiments on the postbuckling behavior
of circular cylindrical shells under hydrostatic pressure. Experimental
Mechanics 13, 299 (1973)
[4] K. A. Seffen, and S. V. Stott. Surface Texturing Through Cylinder Buckling.
Journal of Applied Mechanics, 81 (2014)
[5] Yutaka Nishiyama. Miura folding: Applying origami to space exploration.
IJPAMS, 79, 269 (2012)
[6] Zeming Song et al. Origami lithium-ion batteries. Nat. Comm. 5 (2014)
[7] Shuguang Li et al. Fluid-driven origami-inspired artificial muscles.
PNAS 201713450 (2017)
75
[8] S. Felton et al. A method for building self-folding machines. Science
345, 644 (2014)
[9] L.H. Donnell. Stability of thin-walled tubes under torsion. NACA Report
479 (1933)
[10] N. Yamaki.Elastic stability of circular cylindrical shells. Elsevier, Amsterdam,
Applied Mathematics and Mechanics 27, (1984)
[11] Hunt, Giles W., and Ichiro Ario. Twist buckling and the foldable cylinder:
an exercise in origami International Journal of Non-Linear Mechanics
40, 833 (2005)
[12] T. Yokoyama and K. Nakai. Evaluation of in-plane orthotropic elastic
constants of paper and paperboard. Conference: SEM Annual Conference
& Exposition on Experimental and Applied Mechanics (2007)
[13] Mikael Nygårds and Jean Malnory. Measuring the out-of-plane shear
strength profiles in different paper qualities. Nordic Pulp and Paper Research
Journal, 25 (2010)
[14] Matweb. Aluminum 5052-H19 Foil. ASM Material Data Sheet. Retrieved
from http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=
ma5052h19
[15] Copper Development Association. A Guide to Working With Copper
and Copper Alloys. antimicrobialcopper. (2010)
[16] Memsnet. Material: Copper (Cu), bulk. Memsnet.org. Retrieved from
https://www.memsnet.org/material/coppercubulk/
76
[17] Matweb. Copper, Cu; Annealed. MatWeb. Retrieved from
http://www.matweb.com/search/datasheettext.aspx?matguid=
9aebe83845c04c1db5126fada6f76f7e
[18] Matweb. Overview of materials for Polyethylene Terephthalate
(PET), Unreinforced. Matweb. Retrieved from http:
//www.matweb.com/search/datasheettext.aspx?matguid=
a696bdcdff6f41dd98f8eec3599eaa20
[19] AZO Material. Polyethylene terephthalate (Polyester, PET, PETP)
Material Information. Retrieved from Goodfellow.com http://www.
goodfellow.com/E/Polyethylene-terephthalate.html
[20] Sun-Ting Tsai, Li-Min Wang, et al. Acoustic Emission from Breaking a
Bamboo Chopstick. Phys. Rev. Lett. 116, 035501 (2016).
[21] Alexey G. Murzint, Arthur M. Lesk and Cyrus Chothia. Principles Determining
the Structure of B-Sheet Barrels in Proteins.J. Mol. Biol. 236,
1369 (1994)
Bibliography
[1] Meng-Xue Tsai. Global linguistic structure for both English and Chinese
Corpora. Master’s Thesis of Department of Physics. National Tsing
Hua University (2016)
[2] M. E. J. Newman. Power laws, Pareto distributions and Zipf’s law. Contemporary
Physics 46, 323 (2005)
[3] DOUG BEEFERMAN, ADAM BERGER and JOHN LAFFERTY. Statistical
Models for Text Segmentation.Machine Learning - Special issue on
natural language learning, 34, 177 (1999)
[4] C. Domb, M.S. Green, J.L. Lebowitz. Phase Transitions and Critical Phenomena.
Academic Press, 1-20 (1972-2001)
[5] Wang, Li-Min & Wu, Shan-Jyun. Scaling, Open source project on
Github: https://github.com/shanjgit/Scaling
[6] Gutenberg B, Richter cf. Magnitude and Energy of Earthquakes. Annals
of Geophysics, 9 (1959)
109
[7] William B. Cavnar and John M. Trenkle. N-Gram-Based Text Categorization.
In Proceedings of SDAIR-94, 3rd Annual Symposium on Document
Analysis and Information Retrieval (1994)
[8] Patricia K. Kuhl. EARLY LANGUAGE ACQUISITION: CRACKING THE
SPEECH CODE. Nat. Rev. Neuroscience 5, 831 (2004)
[9] Piantadosi, Steven T. Zipf’s word frequency law in natural language: A
critical review and future directions. Psychon Bull Rev. 21: 1112 (2014).
[10] Sun-Ting Tsai, Li-Min Wang, et al. Acoustic Emission from Breaking a
Bamboo Chopstick. Phys. Rev. Lett. 116, 035501 (2016).
[11] Zipf, G. K. Human behavior and the principle of least effort. Addison-
Wesley Press, Oxford (1949)
[12] (n.d.). References on Zipf’s law. Retrieved from Rockefeller:
https://web.archive.org/web/20021010193014/http://linkage.
rockefeller.edu:80/wli/zipf/
[13] Semantic Depth Analyzer. Retrieved from Semantic-depth: http://1.
1o1.in/en/webtools/semantic-depth (2010).
[14] Dunning, Ted. Accurate methods for the statistics of surprise and coincidence.
Computational Linguistics 19, 61 (1993).
[15] Fedorowicz, Jane. The Theoretical Foundation of Zipf’s Law and Its
Application to the Bibliographic Database Environment. J. Am. Soc. Inf.
Sci., 33: 285 (1982)
110
[16] Xiao, Hang. On the Applicability of Zipf’s Law in Chinese Word Frequency
Distribution. Journal of Chinese Language and Computing 18:
33-46 (2008).
[17] Tsai, S. T. et al. Power-law ansatz in complex systems: Excessive loss of
information. Phys. Rev. E 92, 062925 (2015).
[18] Ma, Wei-Yun & Chen, Keh-Jiann. Introduction to CKIP Chinese Word
Segmentation System for the First International Chinese Word Segmentation
Bakeoff. Proceedings of ACL, Second SIGHAN Workshop
on Chinese Language Processing, 168-171. Retrieved from http://
ckipsvr.iis.sinica.edu.tw/ (2003).
[19] Plag, Ingo. Word-formation in English. (Cambridge University Press,
Cambridge, 2003).
[20] Stribling, Jeremy, Krohn, Max & Aguayo, Dan . SCIgen - An Automatic
CS Paper Generator. Retrieved from https://pdos.csail.mit.
edu/archive/scigen/ (2017)
[21] Conrad, Brian & Mitzenmacher, Michael. Power Laws for Monkeys Typing
Randomly: The Case of Unequal Probabilities. IEEE Transactions on
information theory, 50, 7 (2004).
[22] Chiang, Tung-Hui, Chang, Jing-Shin, Lin, Ming-Yu & Su, Keh-Yih . Statistical
models for word segmentation and unknown resolution. In Proceedings
of ROCLING-92, 121 (1992).
111
[23] Barabasi, Albert-Laszlo & Albert, Reka. Science 286, 509 (1999); Albert,
Reka & Barabasi, Albert-Laszlo. Rev. Mod. Phys. 74, 47 (2002).
[24] The corpora analyzed in this work are listed in https://github.com/
godofhoe/Reference-of-scaling
[25] Shan-Jyun Wu. Fake Script Vietnamese. Retrieved from http://godel.
iis.sinica.edu.tw/CKIP/engversion/20corpus.htm (2017)