On non-expandable cross-bifix-free codes

A cross-bifix-free code of length $n$ over $\mathbb{Z}_q$ is defined as a non-empty subset of $\mathbb{Z}_q^n$ satisfying that the prefix set of each codeword is disjoint from the suffix set of every codeword. Cross-bifix-free codes have found important applications in digital communication systems. One of the main research problems on cross-bifix-free codes is to construct cross-bifix-free codes as large as possible in size. Recently, Wang and Wang introduced a family of cross-bifix-free codes $S_{I,J}^{(k)}(n)$, which is a generalization of the classical cross-bifix-free codes studied early by Lvenshtein, Gilbert and Chee {\it et al.}. It is known that $S_{I,J}^{(k)}(n)$ is nearly optimal in size and $S_{I,J}^{(k)}(n)$ is non-expandable if $k=n-1$ or $1\leq k<n/2$. In this paper, we first show that $S_{I,J}^{(k)}(n)$ is non-expandable if and only if $k=n-1$ or $1\leq k<n/2$, thereby improving the results in [Chee {\it et al.}, IEEE-TIT, 2013] and [Wang and Wang, IEEE-TIT, 2022]. We then construct a new family of cross-bifix-free codes $U^{(t)}_{I,J}(n)$ to expand $S_{I,J}^{(k)}(n)$ such that the resulting larger code $S_{I,J}^{(k)}(n)\bigcup U^{(t)}_{I,J}(n)$ is a non-expandable cross-bifix-free code whenever $S_{I,J}^{(k)}(n)$ is expandable. Finally, we present an explicit formula for the size of $S_{I,J}^{(k)}(n)\bigcup U^{(t)}_{I,J}(n)$.Comment: This paper has been submitted to IEEE T-IT for possible publicatio

Design and Testing of a Biomimetic Pneumatic Actuated Seahorse Tail Inspired Robot

The purpose of this study is to build and test a pneumatically actuated robot based on the biomimetic design of a seahorse tail. McKibben muscles, a form of pneumatic actuator, have been previously used to create highly flexible robots. It has also been discovered that the seahorse tail serves as a highly flexible and prehensile, yet armored appendage. Combining these topics, this research aims to create a robot with the mechanical flexibility of a pneumatic actuator and the protection of a seahorse tail. First, the performance of a miniature McKibben muscle design is examined. Then, the artificial muscles are implemented into a 3D-printed seahorse tail-inspired skeleton. The robot\u27s actuation was observed to determine its maximum bending capacities. The results of the experiments revealed that the miniature McKibben muscles performed comparably to larger sized McKibben muscles previously reported in literature. The pneumatically actuated robot achieved a maximum bend angle of ~22°. Further research is recommended to determine the behaviors of similar robots with additional plates or McKibben muscles spanning shorter plate sequences

Building knowledge around complex objects using InforBright Data Warehousing technology

There are considerable challenges in analysing and reporting on word-based data. Infobright data warehousing technology was used to build knowledge around qualitative data that are subject to human interpretation. Infobright was chosen as a system for implementing the data set because its rough set based intelligence appears to be extensible with moderate effort to implement the data warehousing requirements for automatic interpretation of word based data. An example of social sciences research data was used for illustration

Reading Videogames as (authorless) Literature

This article presents the outcomes of research, funded by the Arts and Humanities Research Council in England and informed by work in the fields of new literacy research, gaming studies and the socio-cultural framing of education, for which the videogame L.A. Noire (Rockstar Games, 2011) was studied within the orthodox framing of the English Literature curriculum at A Level (pre-University) and Undergraduate (degree level). There is a plethora of published research into the kinds of literacy practices evident in videogame play, virtual world engagement and related forms of digital reading and writing (Gee, 2003; Juul, 2005; Merchant, Gillen, Marsh and Davies, 2012; Apperley and Walsh, 2012; Bazalgette and Buckingham, 2012) as well as the implications of such for home / school learning (Dowdall, 2006; Jenkins, 2006; Potter, 2012) and for teachers’ own digital lives (Graham, 2012). Such studies have tended to focus on younger children and this research is also distinct from such work in the field in its exploration of the potential for certain kinds of videogame to be understood as 'digital transformations' of conventional ‘schooled’ literature. The outcomes of this project raise implications of such a conception for a further implementation of a ‘reframed’ literacy (Marsh, 2007) within the contemporary curriculum of a traditional and conservative ‘subject’. A mixed methods approach was adopted. Firstly, students contributing to a gamplay blog requiring them to discuss their in-game experience through the ‘language game’ of English Literature, culminating in answering a question constructed with the idioms of the subject’s set text ‘final examination’. Secondly, students taught their teachers to play L.A. Noire, with free choice over the context for this collaboration. Thirdly, participants returned to traditional roles in order to work through a set of study materials provided, designed to reproduce the conventions of the ‘study guide’ for literature education. Interviews were conducted after each phase and the outcomes informed a redrafting of the study materials which are now available online for teachers – this being the ‘practical’ outcome of the research (Berger and McDougall, 2012). In the act of inserting the study of L.A. Noire into the English Literature curriculum as currently framed, this research moves, through a practical ‘implementation’ beyond longstanding debates around narratology and ludology (Frasca, 2003; Juul, 2005) in the field of game studies (Leaning, 2012) through a direct connection to new literacy studies and raises epistemological questions about ‘subject identity’, informed by Bernstein (1996) and Bourdieu (1986) and the implications for digital transformations of texts for both ideas about cultural value in schooled literacy (Kendall and McDougall, 2011) and the politics of ‘expertise’ in pedagogic relations (Ranciere, 2009, Bennett, Kendall and McDougall, 2012a)

Image-based Quantification of 3D Morphology for Bifurcations in the Left Coronary Artery: Application to Stent Design

Background Improved strategies for stent‐based treatment of coronary artery disease at bifurcations require a greater understanding of artery morphology. Objective We developed a workflow to quantify morphology in the left main coronary (LMCA), left anterior descending (LAD), and left circumflex (LCX) artery bifurcations. Methods Computational models of each bifurcation were created for 55 patients using computed tomography images in 3D segmentation software. Metrics including cross‐sectional area, length, eccentricity, taper, curvature, planarity, branching law parameters, and bifurcation angles were assessed using open‐sources software and custom applications. Geometric characterization was performed by comparison of means, correlation, and linear discriminant analysis (LDA). Results Differences between metrics suggest dedicated or multistent approaches should be tailored for each bifurcation. For example, the side branch of the LCX (i.e., obtuse marginal; OM) was longer than that of the LMCA (i.e., LCXprox) and LAD (i.e., first diagonal; D1). Bifurcation metrics for some locations (e.g., LMCA Finet ratio) provide results and confidence intervals agreeing with prior findings, while revised metric values are presented for others (e.g., LAD and LCX). LDA revealed several metrics that differentiate between artery locations (e.g., LMCA vs. D1, LMCA vs. OM, LADprox vs. D1, and LCXprox vs. D1). Conclusions These results provide a foundation for elucidating common parameters from healthy coronary arteries and could be leveraged in the future for treating diseased arteries. Collectively the current results may ultimately be used for design iterations that improve outcomes following implantation of future dedicated bifurcation stents