SIMULTANEOUS OBSERVATIONS of GIANT PULSES from the CRAB PULSAR, with the MURCHISON WIDEFIELD ARRAY and PARKES RADIO TELESCOPE: IMPLICATIONS for the GIANT PULSE EMISSION MECHANISM

We report on observations of giant pulses from the Crab pulsar performed simultaneously with the Parkes radio telescope and the incoherent combination of the Murchison Widefield Array (MWA) antenna tiles. The observations were performed over a duration of approximately one hour at a center frequency of 1382 MHz with 340 MHz bandwidth at Parkes, and at a center frequency of 193 MHz with 15 MHz bandwidth at the MWA. Our analysis has led to the detection of 55 giant pulses at the MWA and 2075 at Parkes above a threshold of 3.5σ and 6.5σ, respectively. We detected 51% of the MWA giant pulses at the Parkes radio telescope, with spectral indices in the range of -3.6 > α > -4.9 (Sv ∝ vα). We present a Monte Carlo analysis supporting the conjecture that the giant pulse emission in the Crab is intrinsically broadband, the less than 100% correlation being due to the relative sensitivities of the two instruments and the width of the spectral index distribution. Our observations are consistent with the hypothesis that the spectral index of giant pulses is drawn from normal distribution of standard deviation 0.6, but with a mean that displays an evolution with frequency from -3.00 at 1382 MHz, to -2.85 at 192 MHz

Quantifying ionospheric effects on time-domain astrophysics with the Murchison Widefield Array

© 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Refraction and diffraction of incoming radio waves by the ionosphere induce time variability in the angular positions, peak amplitudes and shapes of radio sources, potentially complicating the automated cross-matching and identification of transient and variable radio sources. In this work, we empirically assess the effects of the ionosphere on data taken by the Murchison Widefield Array (MWA) radio telescope. We directly examine 51 h of data observed over 10 nights under quiet geomagnetic conditions (global storm index Kp < 2), analysing the behaviour of short-time-scale angular position and peak flux density variations of around ten thousand unresolved sources. We find that while much of the variation in angular position can be attributed to ionospheric refraction, the characteristic displacements (10-20 arcsec) at 154 MHz are small enough that search radii of 1-2 arcmin should be sufficient for crossmatching under typical conditions. By examining bulk trends in amplitude variability, we place upper limits on the modulation index associated with ionospheric scintillation of 1-3 per cent for the various nights. For sources fainter than ~1 Jy, this variation is below the image noise at typical MWA sensitivities. Our results demonstrate that the ionosphere is not a significant impediment to the goals of time-domain science with the MWA at 154 MHz

Serendipitous discovery of a dying Giant Radio Galaxy associated with NGC 1534, using the murchison widefield array

Recent observations with the Murchison Widefield Array at 185 MHz have serendipitously unveiled a heretofore unknown giant and relatively nearby (z=0.0178) radio galaxy associated with NGC 1534. The diffuse emission presented here is the first indication that NGC 1534 is one of a rare class of objects (along with NGC 5128 and NGC 612) in which a galaxy with a prominent dust lane hosts radio emission on scales of ~700 kpc. We present details of the radio emission along with a detailed comparison with other radio galaxies with discs. NGC 1534 is the lowest surface brightness radio galaxy known with an estimated scaled 1.4-GHz surface brightness of just 0.2 mJy arcmin-2. The radio lobes have one of the steepest spectral indices yet observed: α = -2.1 ± 0.1, and the core to lobe luminosity ratio is <0.1 per cent. We estimate the space density of this low brightness (dying) phase of radio galaxy evolution as 7 × 10-7 Mpc-3 and argue that normal AGN cannot spend more than 6 per cent of their lifetime in this phase if they all go through the same cycle

A Combined Comparative and Phylogenetic Analysis of the Chapacuran Language Family

Contains fulltext : 166431.pdf (publisher's version ) (Open Access) Contains fulltext : 166431suppl.pdf (publisher's version ) (Open Access)30 p

[[alternative]]外語學習者動作事件描述語的認知 : 以臺灣大學生為例

博士[[abstract]]本研究旨在探討分別以英文和中文為母語的外語學習者，對英語動作事件描述的差異性，並討論以中文為母語的外語學習者，如何從他們觀點轉譯所看見的動作事件，其中語言經驗模式、中文詞網、中英文語言結構等都是本研究探討的重點。本文共有三個測驗，以英文為母語的人士者為第一測驗的受試者，他們所使用的動作動詞、路徑、和動作動詞、路徑 和目的地三者配搭都將辨識和歸類。以中文為母語的英語學習者為第二和第三測驗的受試者，他們在測驗二所使用的動作動詞、路徑、和動作動詞、路徑 和目的地三者配搭都將辨識和歸類。在測驗三，參與測驗二的受試者將動作事件的中文描述翻譯成英文，其所使用的英文詞將會和題目的中文詞作比較。測驗一，23位以英文為母語受試者，首先依據料理鼠王的故事選出的18張手繪動作事件圖卡，並自由描述圖卡中的動作事件。結果顯示出受試者的動作動詞、路徑、和動作詞組呈現多樣性。此外動作詞組和目的地連結的模式，也將以圖表方式呈現。測驗二，將90位以中文為母語的英語學習者，依英文能力分為二組，寫出測驗一的18張手繪動作事件圖卡，並自由描述圖中的動作事件。結果顯示英語能力較好者可寫出似英文為母語者的表達動作詞組，但英語能力較差受試者，有較多的動詞詞組趨近於直接中文翻譯的動詞詞組。測驗三，測驗二受試者在一週後作中文動作事件翻譯為英文的測驗。測驗題目作事件也是依據18張測驗一的動作事件圖卡所編制中文句子。受試者句子表達的分析結果將做中、英動作動詞、路徑和動作詞組的三張對照表以顯示其差異性。其結果顯示受試者套用中文動作詞組（方法動詞＋路徑動詞）高於受試者看圖像寫作。本研究的結果回應研究問題，受試者的母語、和他們的語言經驗模式會影響他們在動作動詞、路徑和動作事件句型的表達方式。受試者寫作能力的表現受限於寫作參照的工具，透過看圖寫作勝於中翻英中的方式，受試者比較能呈現英文（動詞＋路徑）的結構。[[abstract]]This paper investigates and compares the expression of motion events between native speakers of English and native Chinese speakers. Learners’ experiencing schema, learners’L1 word net, and cross-linguistic language frameworks are noted as the main foci, while an exploration details how L2 learners interpret motion events from their perception of the world. Three tests were conducted. The first test focused on native English speakers’ use of lexical patterns of motion and their parent relationship with Ground. The second test focused on native Chinese participants’ use of lexical patterns of motion and their parent relationship with Ground. The third test was the supplementary test which is used to study native Chinese participants’ English translation from motion events written in Chinese. 18 hand-drawn pictures containing motion events that were drawn from the story of “Ratatouille” were presented to 23 native English speakers in test 1 and 90 Chinese participants in test 2 who depicted the motion events in the pictures with open-questionnaire format. 90 Chinese participants in test 2 were required to translate these sentences from Chinese to English in test 3 one week after they have completed test 2. The comparison of participants in test 1 and 2 presented that English native speakers used Path to express the relations of Motion and Ground but Chinese participants in test 2 often used Path to express the position of Motion. The analysis of the findings showed Chinese participants focused on the position of motion more than the elaboration of the Motion and Ground when they depicted the motion event in the 18 pictures. Besides, when the meaning of Path of motion in English can be translated as the same meaning of Path verb in Chinese, some students in test 2 used Chinese Path verb as the path of motion to describe the path of motion in their written English. These two findings might explain why Chinese EFL learners with limited English proficiency have difficult in learning or using proper preposition or particles to express the relation of Motion and Ground in English. The comparison of test 2 and test 3 showed that the influence of first language to Chinese participants could be reduced on their written production in English if they depicted the 18 motion events from pictures but not from the written Chinese. Further, the results showed that participants with better English proficiency could produce more lexical patterns of motion corresponded to an English lexical patterns of motion (Motion + Path) then participants with limited English proficiency. Thus, the English proficiency plays an important role when Chinese participants want to reach native speakers like written production.[[tableofcontents]]ACKNOWLEDGMENTS .................................................i 淡江大學論文題要 ................................................ii Abstract ...............................................iv CONTENTS ................................................vi LIST OF TABLES ........................................x LIST OF FIGURES............................ ............xiii CHAPTER 1 INTRODUCTION ...............................1 1.1 Motivation and Background of the Study................1 1.2 Statement of the Problem ......................4 1.3 Purpose of the Study and Research Questions...........8 1.4 Significance of the Study .....................11 1.5 Definition of key Terms ..............................12 1.6 Organization of the Study ...... ..............15 CHAPTER 2 LITERATURE REVIEW ..............................16 2.1 Language and Cognition ...................... .......16 2.1.1 Slobin “ Speaking and thinking” hypothesis.......19. 2.1.2 Categorization of Language.........................21 2.1.3 Grammar in Cognition ..............................25 2.1.4 Conceptual Blending Networks….....................27 2.1.5 Concepts and Elaboration ....................30 2.2 Lexical Concept and Cognitive Model..................33 2.3 Cognition and Culture ..............................35 2.4 Conception of Events ..............................41 2.4.1 Spatial schema ..............................43 2.5 Cross- Linguistic typology in Motion Events..........47 2.5.1 Overview of the phenomenon of typology in motion event....................................................47 2.5.2 Typology of Motion Event in English................50 2.5.3 Typology of Motion Event in Chinese................56 2.5.4 Cross-Linguistic Differences in Motion Events: English and Chinese................................63 2.5.5 Difficulty of learning to express motion in a second language...........................................66 2.6 Summary..............................................68 CHAPTER 3 METHOD .......................................70 3.1 Pilot Study .......................................70 3.2 Formal Study .......................................73 3.3 Subjects .......................................74 3.3.1 Subjects of Test 1 ..............................74 3.3.2 Subjects of test 2 and 3 .....................74 3.4 Materials of the study ..............................75 3.4.1 Materials for test 1 ..............................75 3.4.2 Materials for Test 2 ..............................77 3.4.3 Materials for Test 3 ..............................78 3.5 Procedure of the study ..............................78 3.5.1 Procedure of Test 1 ..............................79 3.5.2 Procedure of Test 2 ..............................80 3.5.3 Procedure of the Test 3............................81 3.6 Data collection......................................82 3.6.1 Test 1 .......................................82 3.6.2 Test 2 .......................................82 3.6.3 Test 3 .......................................82 3.7 Coding and Analysis ..............................83 CHAPTER 4 RESULTS .......................................87 4.1 Results of Test One ..............................87 4.1.1 Motion and Path expressions for each picture.......88 4.1.2 Results of analysis of lexical patterns (Motion + Path) and its Ground.....................................91 4.1.2.1 Results of analysis of lexical patterns (Motion + Path ) and its Ground in category of directional path. ...............................................92 4.1.2.2 Results of analysis of lexical patterns (Motion + Path ) and its Ground in category of ground path........ 102 4.2 The Results of Test II .........................113 4.2.1 Descriptive analysis of the vocabulary pretest of group A and B ......................................113 4.2.2 Category of Motion and Path in Test Two .........114 4.2.3 The Parent Relation Between the Lexical Patterns of Motion and its Ground in Test Two .................120 4.2.3.1 Results of analysis of lexical patterns (Motion + Path ) and its Ground in category of directional path. .121 4.2.3.2 Results of analysis of lexical patterns (Motion + Path ) and its Ground in category of ground path.........133 4.2.4 The Structure of Lexical Patterns of Motion........146 4.3 The Results of Test Three............................149 4.4. The Comparison of test 2 and test 3.................153 4.5 Summary..............................................155 CHAPTER 5 DISCUSSION.....................................156 5.1 In what ways are English L2 written sentences related to motion events influenced by L1 Chinese language construction?............................................156 5.2 Are English L2 written sentences related to motion influenced by the lexical semantic characteristics of Chinese verbs?...........................................164 5.3 Are English L2 written sentences related to motion influenced by Chinese L1 learners’ experiencing schema?..................................................170 5.4 Does a learner’s second language proficiency influence their interpretation from visual images to written production?..............................................174 5.5 Summary..............................................179 CHAPTER 6 CONCLUSION.....................................181 6.1 Summary of the findings .............................181 6.2 Pedagogical implications.............................184 6.3 Limitations and suggestions for future study.........186 REFERENCES...............................................188 Appendix.................................................204 LIST OF TABLES Table 2.1 Sample of Lexicon……………………………………………………. 31 Table 2.2 conceptual change induced by L2 learning…………………………… 39 Table 3.1 The background information of participants in test 1………………… Table 3.2 Class of selected motion verbs……………………………………….. Table 3.3 Class of selected preposition………………………………………….. 74 76 77 Table 4.1 Motion expressions in each picture…………………………………… 89 Table 4.2 Path description and its frequency for each picture…………………... 90 Table 4.3 Figure and Ground of picture 10, 11, 12, and 13……………………... Table 4.4 The high and low frequency of lexical pattern of motions in figure 4.1-4.4……………………………………………………………… Table 4.5 Motion and Path of the category of directional spatial path………….. Table 4.6 Figure and Ground of picture 3, 5, 8, and 18………………………… Table 4.7 The high and low frequency of lexical pattern of motions in each figure………………………………………………………………… Table 4.8 Motion and Path of the category of directional movement path……… 93 93 97 97 98 101 Table 4.9 Figure and Ground of pictures in two categories of ground path…….. Table 4.10 The high and low frequency of lexical patterns of motions in picture 15, 16, 17, 1, 2, 4, 6, 9, and 14………………………………………. Table 4.11 Motion and Path of the category of ground path…………………… 102 103 112 Table 4.12 Descriptive analyses……………………………………………… Table 4.13 Independent sample T-test…………………………………….. 114 114 Table 4.14 Variable of Motion and the frequency of each motion of Group A… 115 Table 4.15 Variable of Motion and the frequency of each motion of Group B… 116 Table 4.16 The path expressions and their frequency in group A and group B…. 119 Table 4.17 Figure and Ground of pictures in two categories of directional path 121 Table 4.18 The comparsion of Motin + Path pattern of picture 10-13…………. Table 4.19 The high frequency of lexical pattern of motion in picture10-13…… 126 127 Table 4.20 The category of Motion and Path of picture 3,5,8,18 in test 1 and 2.. 132 Table 4.21 The high frequency of lexical pattern of motion in picture 3,5,8,18.. Table 4.22 Figure and Ground of pictures in two categories of ground path…… 133 134 Table 4.23 The category of Motion and Path of picture 15, 16, and 17 in test 1 and test 2………………………………………………………….. 137 Table 4.24 The high frequency of lexical pattern of picture 15, 16, and 17 in test 1 and 2…………………………………………………………. 137 Table 4.25. Motion and Path of Picture 1,2,4,6,7,9,14 in test 1 and test2 … 145 Table 4.26 The high frequency of lexical pattern of motion in picture 1,2, 4, 6,7,9, and 14………………………………………………………. 146 Table 4.27 Analysis of Chinese participants ‘motion events……………….. 147 Table 4.28 Category of lexical patterns of motion in test 2……………………. 148 Table 4.29 Categories of Motion in Chinese and their translation in English….. 150 Table 4.30 Categories of Path verbs in Chinese and their translation in English.. 151 Table 4.31 Lexical expressions of Motion in Chinese and their translation in English…………………………………………………………… 152 Table 4.32 The comparison of Motion and Path among test 1, test 2, and test 3.. 154 Table 4.33 Categories of Chinese participants’ motion events ……………… 154 Table 5.1 The analysis of non qualified Motion + path lexical patterns of motion……………………………………………………………… 157 Table 5.2 The list of Motion used alone in lower case…………………………. 159 Table 5.3 Similarity and dissimilarity of motion in test 1 and test 2……………. 167 Table 5.4 The results of the comparison of the Path in Group A and B with native speakers in test 1……………………………………………… 176 LIST OF FIGURES Figure 2.1 The bike is in front of the car………………………………………... 17 Figure 2.2 Integration of Frames and Domains…………………………………. 23 Figure 2.3 Semantic category “in” and “on” in English and Chinese…………… 25 Figure2. 4. Funconnier and Turner Blending Network Model………………….. 28 Figure 2.5 An example illustrating Reigeluth’s ideas…………………………… 30 Figure 2.6 The relationship between Conceptual system and Linguistic system.. 34 Figure 2.7 A sample of role archetypes…………………………………………. 42 Figure 2.8 Action Chain of Billiard-ball Model………………………………… 43 Figure 2.9 The Elaboration with the Ground…………………………………… 54 Figure 2.10 Jeckendoff’s (1983) typology of path……………………………… 55 Figure 2.11 Syntactic mapping of macro-event in verb-framed languages…….. 56 Figure 3.1 The Procedure of implementing the study…………………………… 72 Figure 3.2 The relationship among three tests…………………………………... 73 Figure 3.3 Procedure of the study……………………………………………….. 79 Figure 3.4 Procedure of test 1…………………………………………………… 80 Figure 3.5 Procedure of test 2…………………………………………………… 81 Figure 4.1 Parent relations of lexical express of Motion and its Ground for picture 10……………………………………………………………… 94 Figure 4.2 Parent relation of lexical express of Motion and its Ground in picture 11 ………………………………………………………….... 95 Figure 4.3 Parent relation of lexical express of Motion and its Ground for picture12……………………………………………………………. 95 Figure 4.4 Parent relation of lexical express of motion and its ground for picture 13……………………………………………………………. 96 Figure 4.5 Parent relations of lexical patterns of motion and its ground for picture 3…………………………………………………………….. 99 Figure 4.6 Parent relations of lexical expression of Motion and its Ground for picture 5…………………………………………………………….. 100 Figure 4.7 Parent relations of lexical express of Motion and its Ground for picture8…………………………………………………………….. 100 Figure 4.8 Parent relations of lexical express of Motion and its Ground for picture18………………………………………………………… 101 Figure 4.9 Parent relations of lexical express of Motion and its Ground for picture15……………………………………………………………. 104 Figure 4.10 parent relations of lexical express of motions and its Ground for picture 16………………………………………………………… 105 Figure 4.11 Parent relations of lexical express of Motion and its Ground for picture 17………………………………………………………… 105 Figure 4.12 Parent relations of lexical patterns of Motion and its Ground for picture 1…………………………………………………………… 106 Figure 4.13 Parent relations of lexical express of Motion and its Ground for picture 2………………………………………………………… 107 Figure 4.14 parent relations of lexical patterns of Motion and its Ground for picture 4………………………………………………………… 108 Figure 4.15 parent relations of lexical patterns of Motion and its Ground for picture 6…………………………………………………………… 108 Figure 4.16 Parent relations of lexical pattern of Motion and its Ground for picture 7………………………………………………………… 110 Figure 4.17 Parent relation of lexical express (Motion+ Path) and its Ground for picture 9…………………………………………………………… 110 Figure 4.18 Parent relations of lexical pattern of Motion and its Ground for picture 14…………………………………………………………… 111 Figure 4.19 Parent relations of lexical express of Motion and its Ground for picture 10………………………………………………………….. 123 Figure 4.20 Parent relations of lexical express of Motion and its Ground in picture 11………………………………………………………….. 123 Figure 4.21 Parent relations of lexical express of Motion and its Ground in picture 12……………………………………………………….. 124 Figure 4.22 Parent relations of lexical express of Motion and its Ground in picture 13………………………….…………………………….. 125 Figure 4.23 Parent relations of lexical express of Motion and its Ground in picture3…………………………………………………………… 128 Figure 4.24 Parent relations of lexical express of Motion and its Ground in picture 5…………………………………………………………….. 129 Figure 4.25 Parent relations of lexical express of Motion and its Ground in picture 8………………………………………………………….. 130 Figure 4.26 Parent relations of lexical express of Motion and its Ground in picture 18……………………………………………………….. 131 Figure 4.27 Parent relations of lexical express of motion and its ground for picture15……………………………………………………………. 135 Figure 4.28 Parent relations of lexical express of Motions and its Ground for picture16…………………………………………………………… 136 Figure 4.29 Parent relations of lexical express of Motion and its Ground for picture 17……………………………………………………….. 136 Figure 4.30 Parent relations of lexical express of Motion and its Ground for picture 1………………………………………………………… 139 Figure 4.31 Parent relations of lexical express of Motion and its Ground for picture 2…………………………………………………………… 139 Figure 4.32 Parent relations of lexical express of Motion and its Ground for picture 4………………………………………………………….. 140 Figure 4.33 parent relations of lexical express of motion and its ground for picture 6…………………………………………………………… 141 Figure 4.34 Parent relations of lexical express of motion and its ground for picture 7…………………………………………………………. 142 Figure 4.35 Parent relations of lexical express of motion and its ground for picture 9………………………………………………………… 143 Figure 4.36 Parent relations of lexical express of motion and its ground for picture 14………………………………………………………. 144 Figure 5.1 the motion of rise and ju(lift)………………………………………… 166 Figure 5.2The direction of crawl and climb in English and in Chinese………… 168 Figure 5.3 Lexical concepts of motion event and cognitive model……………... 170 Figure 5.4 The spatial schema of pao and run………………………………….. 171 Figure 5.5 the cognitive mapping of the path down and over of motion push…... 173 Figure 5.6 the comparison with native English speakers between Group A and Group B in motion………………………………………………….. 175[[note]]學號: 893010222, 學年度: 10

Does horizontal transmission invalidate cultural phylogenies?

Phylogenetic methods have recently been applied to studies of cultural evolution. However, it has been claimed that the large amount of horizontal transmission that sometimes occurs between cultural groups invalidates the use of these methods. Here, we use a natural model of linguistic evolution to simulate borrowing between languages. The results show that tree topologies constructed with Bayesian phylogenetic methods are robust to realistic levels of borrowing. Inferences about divergence dates are slightly less robust and show a tendency to underestimate dates. Our results demonstrate that realistic levels of reticulation between cultures do not invalidate a phylogenetic approach to cultural and linguistic evolution