Signalling conditional relations

We investigate how discourse relations and their subtypes are signalled, extending the set of discourse signals from connectives and lexical cue phrases to the wide range of semantic, syntactic, and orthographic signals of the RST Signalling Corpus (Das, Debopam & Maite Taboada. 2018. RST signalling corpus. Language Resources and Evaluation 52. 149–184). This extension requires re-evaluating previous predictions on discourse signalling, in particular, those of Sanders, Ted. 2005. Coherence, causality and cognitive complexity in discourse. In M. Aurnague, M. Bras, A. Le Draoulec & L. Vieu (eds.), Proceedings/Actes SEM-05, first international symposium on the exploration and modelling of meaning, 105–114. Biarritz causality-by-default hypothesis, the hypothesis of uniform information density (Frank, Austin & Florian Jaeger. 2008. Speaking rationally: Uniform information density as an optimal strategy for language production. In Proceedings of the 30th annual meeting of the Cognitive Science Society, 933–938. https://escholarship.org/uc/item/7d08h6j4 (accessed 18 May 2022)), and the hypothesis that discourse is continuous by preference (Segal, Erwin, Judith Duchan & Paula Scott. 1991. The role of interclausal connectives in narrative structuring. Discourse Processes 14. 27–54; Murray, John. 1997. Connectives and narrative text. Memory and Cognition 25. 227–236). We evaluate the predictions of these theories on the conditional relations in the RST Discourse Treebank (Carlson, Lynn, Daniel Marcu & Mary Ellen Okurowski. 2002. RST Discourse Treebank. LDC2002T07. Philadelphia: Linguistic Data Consortium), using causal relations as a control group. Informativity and continuity are operationalized in terms of semantic complexity and Givón, Talmy. 1993. English grammar: A function-based introduction, vol. 2. Amsterdam: John Benjamins dimensions of deictic shift. Our results show that the hypotheses make accurate predictions only for the relation groups in their entirety but not for the observed in-group variation, in particular, the low amount of marking for the hypothetical subtype of conditional relations. We attribute this difference to the distribution of intra- and inter-sentential occurrences across the conditional subtypes: intra-sentential relations are consistently more marked than inter-sentential ones, and hypothetical relations are special in that they appear predominantly inter-sententially.Peer Reviewe

Discourse Relations and Evaluation

We examine the role of discourse relations (relations between propositions) in the interpretation of evaluative or opinion words. Through a combination of Rhetorical Structure Theory or RST (Mann & Thompson, 1988) and Appraisal Theory (Martin & White, 2005), we analyze how different discourse relations modify the evaluative content of opinion words, and what impact the nucleus-satellite structure in RST has on the evaluation. We conduct a corpus study, examining and annotating over 3,000 evaluative words in 50 movie reviews in the SFU Review Corpus (Taboada, 2008) with respect to five parameters: word category (nouns, verbs, adjectives or adverbs), prior polarity (positive, negative or neutral), RST structure (both nucleus-satellite status and relation type) and change of polarity as a result of being part of a discourse relation (Intensify, Downtone, Reversal or No Change). Results show that relations such as Concession, Elaboration, Evaluation, Evidence and Restatement most frequently intensify the polarity of the opinion words, although the majority of evaluative words (about 70%) do not undergo changes in their polarity because of the relations they are a part of. We also find that most opinion words (about 70%) are positioned in the nucleus, confirming a hypothesis in the literature, that nuclei are the most important units when extracting evaluation automatically

Open inverted bell and bell formation during the washing of vials

A range of fascinating flow features was observed while cleaning or filling the medicine or liquid vials in the kitchen sink by serendipity. Here, we present the formation of an open inverted bell and bell-shaped flow structures formed from the water sheet in a new geometric arrangement, hitherto unknown. When a laminar jet impinges on the surface of the liquid in the vial of marginally larger or similar diameter, an inverted open water bell is formed, which gradually changes into a flat water sheet to a classical water bell as the flow rate is increased. The inverted water bell structures disintegrate by forming water ridges which finally break down into different sizes of droplets

RST Signalling Corpus: A Corpus of Signals of Coherence Relations

We present the RST Signalling Corpus (Das et al. in RST signalling corpus, LDC2015T10. https://catalog.ldc.upenn.edu/LDC2015T10, 2015), a corpus annotated for signals of coherence relations. The corpus is developed over the RST Discourse Treebank (Carlson et al. in RST Discourse Treebank, LDC2002T07. https://catalog.ldc.upenn.edu/LDC2002T07, 2002) which is annotated for coherence relations. In the RST Signalling Corpus, these relations are further annotated with signalling information. The corpus includes annotation not only for discourse markers which are considered to be the most typical (or sometimes the only type of) signals in discourse, but also for a wide array of other signals such as reference, lexical, semantic, syntactic, graphical and genre features as potential indicators of coherence relations. We describe the research underlying the development of the corpus and the annotation process, and provide details of the corpus. We also present the results of an inter-annotator agreement study, illustrating the validity and reproducibility of the annotation. The corpus is available through the Linguistic Data Consortium, and can be used to investigate the psycholinguistic mechanisms behind the interpretation of relations through signalling, and also to develop discourse-specific computational systems such as discourse parsing applications

Measurement of Free Stream Turbulence: It’s Modeling and Computations

Present research was initiated to study effects of free stream turbulence (FST) on flow instability and transition. Instabilities of some flows have been investigated qualitatively with respect to FST- but scant attention has been paid to compute extrinsic dynamics of flows due to FST. In actual flows, omnipresent background disturbances, e.g. FST triggers transition to turbulence. The motivation for the present work is to characterize and model FST, based on it’s statistics, obtained from wind tunnel and flight test experiments. The developed model is applied to numerically study the receptivity of flow past circular cylinder to the FS

Encryption and Decryption of Images with Pixel Data Modification Using Hand Gesture Passcodes

To ensure data security and safeguard sensitive information in society, image encryption and decryption as well as pixel data modifications, are essential. To avoid misuse and preserve trust in our digital environment, it is crucial to use these technologies responsibly and ethically. So, to overcome some of the issues, the authors designed a way to modify pixel data that would hold the hidden information. The objective of this work is to change the pixel values in a way that can be used to store information about black and white image pixel data. Prior to encryption and decryption, by using Python we were able to construct a passcode with hand gestures in the air, then encrypt it without any data loss. It concentrates on keeping track of simply two pixel values. Thus, pixel values are slightly changed to ensure the masked image is not misleading. Considering that the RGB values are at their border values of 254, 255 the test cases of masking overcome issues with the corner values susceptibility

Annotation upon Annotation: Adding Signalling Information to a Corpus of Discourse Relations

We present an annotation effort that involves adding a new layer of annotation to an existing corpus. We are interested in how rhetorical relations are signalled in discourse, and thus begin with a corpus already annotated for rhetorical relations, to which we add signalling information. We show that a very large number of relations carry signals that identify them as such. The detailed, extensive analysis of signals in the corpus will aid research in the automatic parsing of discourse relations