• Self-supervised monocular image depth learning and confidence estimation

      Chen, Long; Tang, Wen; Wan, Tao Ruan; John, Nigel W.; Bournemouth University; University of Bradford; University of Chester
      We present a novel self-supervised framework for monocular image depth learning and confidence estimation. Our framework reduces the amount of ground truth annotation data required for training Convolutional Neural Networks (CNNs), which is often a challenging problem for the fast deployment of CNNs in many computer vision tasks. Our DepthNet adopts a novel fully differential patch-based cost function through the Zero-Mean Normalized Cross Correlation (ZNCC) to take multi-scale patches as matching and learning strategies. This approach greatly increases the accuracy and robustness of the depth learning. Whilst the proposed patch-based cost function naturally provides a 0-to-1 confidence, it is then used to self-supervise the training of a parallel network for confidence map learning and estimation by exploiting the fact that ZNCC is a normalized measure of similarity which can be approximated as the confidence of the depth estimation. Therefore, the proposed corresponding confidence map learning and estimation operate in a self-supervised manner and is a parallel network to the DepthNet. Evaluation on the KITTI depth prediction evaluation dataset and Make3D dataset show that our method outperforms the state-of-the-art results.
    • Sketching Designs Using the Five Design-Sheet Methodology

      Roberts, Jonathan C.; Headleand, Christopher J.; Ritsos, Panagiotis D.; University of Bangor, University of Bangor, University of Chester (IEEE, 2015-08-12)
      Sketching designs has been shown to be a useful way of planning and considering alternative solutions. The use of lo-fidelity prototyping, especially paper-based sketching, can save time, money and converge to better solutions more quickly. However, this design process is often viewed to be too informal. Consequently users do not know how to manage their thoughts and ideas (to first think divergently, to then finally converge on a suitable solution). We present the Five Design Sheet (FdS) methodology. The methodology enables users to create information visualization interfaces through lo-fidelity methods. Users sketch and plan their ideas, helping them express different possibilities, think through these ideas to consider their potential effectiveness as solutions to the task (sheet 1); they create three principle designs (sheets 2,3 and 4); before converging on a final realization design that can then be implemented (sheet 5). In this article, we present (i) a review of the use of sketching as a planning method for visualization and the benefits of sketching, (ii) a detailed description of the Five Design Sheet (FdS) methodology, and (iii) an evaluation of the FdS using the System Usability Scale, along with a case-study of its use in industry and experience of its use in teaching.
    • SLAM-based dense surface reconstruction in monocular Minimally Invasive Surgery and its application to Augmented Reality

      Chen, Long; Tang, Wen; John, Nigel W.; Wan, Tao R.; Zhang, Jian Jun; Bournemouth University; University of Chester; University of Bradford (Elsevier, 2018-02-08)
      Background and Objective While Minimally Invasive Surgery (MIS) offers considerable benefits to patients, it also imposes big challenges on a surgeon's performance due to well-known issues and restrictions associated with the field of view (FOV), hand-eye misalignment and disorientation, as well as the lack of stereoscopic depth perception in monocular endoscopy. Augmented Reality (AR) technology can help to overcome these limitations by augmenting the real scene with annotations, labels, tumour measurements or even a 3D reconstruction of anatomy structures at the target surgical locations. However, previous research attempts of using AR technology in monocular MIS surgical scenes have been mainly focused on the information overlay without addressing correct spatial calibrations, which could lead to incorrect localization of annotations and labels, and inaccurate depth cues and tumour measurements. In this paper, we present a novel intra-operative dense surface reconstruction framework that is capable of providing geometry information from only monocular MIS videos for geometry-aware AR applications such as site measurements and depth cues. We address a number of compelling issues in augmenting a scene for a monocular MIS environment, such as drifting and inaccurate planar mapping. Methods A state-of-the-art Simultaneous Localization And Mapping (SLAM) algorithm used in robotics has been extended to deal with monocular MIS surgical scenes for reliable endoscopic camera tracking and salient point mapping. A robust global 3D surface reconstruction framework has been developed for building a dense surface using only unorganized sparse point clouds extracted from the SLAM. The 3D surface reconstruction framework employs the Moving Least Squares (MLS) smoothing algorithm and the Poisson surface reconstruction framework for real time processing of the point clouds data set. Finally, the 3D geometric information of the surgical scene allows better understanding and accurate placement AR augmentations based on a robust 3D calibration. Results We demonstrate the clinical relevance of our proposed system through two examples: a) measurement of the surface; b) depth cues in monocular endoscopy. The performance and accuracy evaluations of the proposed framework consist of two steps. First, we have created a computer-generated endoscopy simulation video to quantify the accuracy of the camera tracking by comparing the results of the video camera tracking with the recorded ground-truth camera trajectories. The accuracy of the surface reconstruction is assessed by evaluating the Root Mean Square Distance (RMSD) of surface vertices of the reconstructed mesh with that of the ground truth 3D models. An error of 1.24mm for the camera trajectories has been obtained and the RMSD for surface reconstruction is 2.54mm, which compare favourably with previous approaches. Second, in vivo laparoscopic videos are used to examine the quality of accurate AR based annotation and measurement, and the creation of depth cues. These results show the potential promise of our geometry-aware AR technology to be used in MIS surgical scenes. Conclusions The results show that the new framework is robust and accurate in dealing with challenging situations such as the rapid endoscopy camera movements in monocular MIS scenes. Both camera tracking and surface reconstruction based on a sparse point cloud are eff active and operated in real-time. This demonstrates the potential of our algorithm for accurate AR localization and depth augmentation with geometric cues and correct surface measurements in MIS with monocular endoscopes.
    • Stigmergic Interoperability for Autonomic Systems: Managing Complex Interactions in Multi-Manager Scenarios

      Eze, Thaddeus; Anthony, Richard; University of Chester; University of Greenwich (IEEE, 2016-09-01)
      The success of autonomic computing has led to its popular use in many application domains, leading to scenarios where multiple autonomic managers (AMs) coexist, but without adequate support for interoperability. This is evident, for example, in the increasing number of large datacentres with multiple managers which are independently designed. The increase in scale and size coupled with heterogeneity of services and platforms means that more AMs could be integrated to manage the arising complexity. This has led to the need for interoperability between AMs. Interoperability deals with how to manage multi-manager scenarios, to govern complex coexistence of managers and to arbitrate when conflicts arise. This paper presents an architecture-based stigmergic interoperability solution. The solution presented in this paper is based on the Trustworthy Autonomic Architecture (TAArch) and uses stigmergy (the means of indirect communication via the operating environment) to achieve indirect coordination among coexisting agents. Usually, in stigmergy-based coordination, agents may be aware of the existence of other agents. In the approach presented here in, agents (autonomic managers) do not need to be aware of the existence of others. Their design assumes that they are operating in 'isolation' and they simply respond to changes in the environment. Experimental results with a datacentre multi-manager scenario are used to analyse the proposed approach.
    • Swarm Communication by Evolutionary Algorithms

      Vaughan, Neil; University of Chester (IEEE, 2018-05-27)
      This research has applied evolutionary algorithms to evolve swarm communication. Controllers were evolved for colonies of artificial simulated ants during a food foriaging task which communicate using pheromone. Neuroevolution enables both weights and the topology of the artificial neural networks to be optimized for food foriaging. The developed model results in evolution of ants which communicate using pheromone trails. The ants successfully collect and return food to the nest. The controller has evolved to adjust the strength of pheromone which provides a signal to guide the direction of other ants in the colony by hill climbing strategy. A single ANN controller for ant direction successfully evolved which exhibits many separate skills including food search, pheromone following, food collection and retrieval to the nest.
    • A Tablet-based Virtual Environment for Neurosurgery Training

      John, Nigel W.; Phillips, Nicholas I.; ap Cenydd, Llyr; Coope, David; Carleton-Bland, Nick; Kamaly-Asl, Ian; Grey, William P.; University of Chester, Leeds General Infirmary, Bangor University, University of Manchester, Cardiff University (MIT Press, 2015-10-15)
      The requirement for training surgical procedures without exposing the patient to additional risk is well accepted and is part of a national drive in the UK and internationally. Computer-based simulations are important in this context, including neurosurgical resident training. The objective of this study is to evaluate the effectiveness of a custom built virtual environment in assisting training of a ventriculostomy procedure. The training tool (called VCath) has been developed as an app for a tablet platform to provide easy access and availability to trainees. The study was conducted at the first boot camp organized for all year one trainees in neurosurgery in the UK. The attendees were randomly distributed between the VCath training group and the Control group. Efficacy of performing ventriculostomy for both groups was assessed at the beginning and end of the study using a simulated insertion task. Statistically significant changes in performance of selecting the burr hole entry point, the trajectory length and duration metrics for the VCath group, together with a good indicator of improved normalized jerk (representing the speed and smoothness of arm motion), all suggest that there has been a higher level cognitive benefit to using VCath. The app is successful as it is focused on the cognitive task of ventriculostomy, encouraging the trainee to rehearse the entry point and use anatomical landmarks to create a trajectory to the target. In straight-line trajectory procedures such as ventriculostomy, cognitive task based education is a useful adjunct to traditional methods and may reduce the learning curve and ultimately improve patient safety.
    • Thermophoresis effect on the free convective flow in a differentially heated square cavity

      Pop, Serban R.; Grosan, Teodor; University of Chester; Babes-Bolyai University of Cluj Napoca (Begell House, 2015)
      A numerical analysis is made for thermophoretic transport of small particles through the convective flow in a differentially heated square cavity. The governing gas-particle partial differential equations are solved numerically for some values of the considered parameters to investigate their influence on the flow, heat, and mass transfer patterns. It is found that the effect of thermophoresis can be quite significant in appropriate situations.
    • Throwing sheep in the bandroom: Visualising a social and economic network of musicians in Cheshire and North Wales

      Southall, Helen; University of Chester (2012-07-25)
      The aim of this session is to apply some of the visual and technological tools of 21st-Century online social networking, e.g. network visualisation using "friend wheels", to a densely interconnected network of jazz and dance band musicians active in the Chester (UK) area in the 1950s, as revealed by research on the "hidden history" of live music in the area. Over 30 interviews with musicians, dancers and promoters have been collected, plus more than 200 photographs from personal collections, and an M.U. diary/address book belonging to local bandleader Wilf Field. The recent dramatic growth of online social networks such as Facebook, LinkedIn and MySpace has led to a revival of interest in the economic importance of social networks; Fraser and Dutta’s "Throwing Sheep in the Boardroom" provides an interesting survey of the issues, and was an inspiration for this session. But working musicians have long known the importance of knowing (and impressing) the "right people" in order to get work. Have social networks changed fundamentally since the advent of Web 2.0, or were they always there, and just a little harder to visualise when held in a pocket diary, rather than displayed on a Facebook wall?
    • Total war and its effects on the live music industry in Cheshire and North Wales

      Southall, Helen; University of Chester (University of Chester, 2014-10-03)
      Given the profound effect which World War II had on the economy of the UK as a whole, it would be surprising if specific areas of that economy – such as live music in the provinces – were not affected as well. How did ‘total war’ affect the live music industry on a local level? Evidence I have collected for a study of musicians active in and around Chester during the period suggests that the large number of military bases in the area, combined with the effects of other wartime factors such as conscription, rationing and the need to maintain both military and civilian morale, did indeed affect the size and nature of the market for live dance music locally. For instance, the large US Air Force base at Burtonwood was a source of work for local musicians, as well as an opportunity to mix with American musicians and music fans. As well as presenting information obtained through interviews with musicians and their relatives, I will also look briefly at what happened to the musicians and the bands after the war, when economic and social conditions changed again, at the same time as advances occurred in music-related technology.
    • Towards Cyber-User Awareness: Design and Evaluation

      Oyinloye, Toyosi; Eze, Thaddeus; Speakman, Lee; University of Chester
      Human reliance on interconnected devices has given rise to a massive increase in cyber activities. There are about 17 billion interconnected devices in our World of about 8 billion people. Like the physical world, the cyber world is not void of entities whose activities, malicious or not, could be detrimental to other users who remain vulnerable as a result of their existence within cyberspace. Developments such as the introduction of 5G networks which advances communication speed among interconnected devices, undoubtedly proffer solutions for human living as well as adversely impacting systems. Vulnerabilities in applications embedded in devices, hardware deficiencies, user errors, are some of the loopholes that are exploited. Studies have revealed humans as weakest links in the cyber-chain, submitting that consistent implementation of cyber awareness programs would largely impact cybersecurity. Cyber-active systems have goals that compete with the implementation of cyber awareness programs, within limited resources. It is desirable to have cyber awareness systems that can be tailored around specific needs and considerations for important factors. This paper presents a system that aims to promote user awareness through a flexible, accessible, and cost-effective design. The system implements steps in a user awareness cycle, that considers human-factor (HF) and HF related root causes of cyber-attacks. We introduce a new user testing tool, adaptable for administering cybersecurity test questions for varying levels and categories of users. The tool was implemented experimentally by engaging cyber users within UK. Schemes and online documentations by UK Cybersecurity organisations were harnessed for assessing and providing relevant recommendations to participants. Results provided us with values representing each participants’ notional level of awareness which were subjected to a paired-T test for comparison with values derived in an automated assessment. This pilot study provides valuable details for projecting the efficacy of the system towards improving human influence in cybersecurity.
    • Towards Organisational Learning Enhancement: Assessing Software Engineering Practice

      Fannoun, Sufian; Kerins, John; University of Chester (Emerald Publishing Limited, 2018-12-17)
      • Purpose – Issues surrounding knowledge management, knowledge transfer and learning within organisations challenge continuity and resilience in the face of changing environments. While initiatives are principally applied within large organisations, there is scope to assess how the processes are handled within small and medium enterprises (SMEs) and to consider how they might be enhanced. This paper presents an evaluation of practice within an evolving software development unit to determine what has been learned and how the knowledge acquired has been utilised to further organisational development. These results provide the basis for the design and implementation of a proposed support tool to enhance professional practice. • Design/methodology/approach – A small software development unit, which has successfully delivered bespoke systems since its establishment a number of years ago, was selected for analysis. The unit operates as a team whose actions and behaviours were identified and validated by the following means: in-depth interviews were carried out with each member of the team to elicit an understanding of individual and collective development. Interview data were recorded and transcribed and subjected to qualitative analysis to identify key themes underpinning knowledge acquisition and utilisation. Samples of project documentation were scrutinised to corroborate interview data. After analysing the data, a focus-group meeting was held to validate the results and to generate further insights into learning within the team. • Findings - Qualitative analysis of the data revealed key changes in thinking and practice within the team as well as insight into the development of individual and collective contextual knowledge, tacit understanding and learning. This analysis informed the proposal of a bespoke, lightweight, web-based system to support knowledge capture and organisational learning (OL). This approach has the potential to promote resilience and to enhance practice in similar small or start-up enterprises. • Research limitations/implications – Purposeful sampling was used in selecting a small software development team. This enabled in-depth interviewing of all members of the team. This offered a rich environment from which to derive awareness and understanding of individual and collective knowledge acquisition and learning. Focusing on a single small enterprise limits the extent to which the findings can be generalised. However, the research provides evidence of effective practice and learning and has identified themes for the development of a support tool. This approach can be extended to similar domains to advance research into learning and development. • Practical implications – Results of the work undertaken so far have generated promising foundations for the proposed support tool. This offers software developers a system within which they can reflect upon, and record, key learning events affecting technical, managerial and professional practice. • Originality/value – Small enterprises have limited resources to support OL. The qualitative research undertaken so far has yielded valuable insight into the successful development of a single software development team. The construction of a support tool to enhance knowledge acquisition and learning has the capacity to consolidate valuable, and potentially scarce, expertise. It also has the potential to facilitate further research to determine how the prototype might be extended or revised to improve its contribution to the team’s development.
    • Training Powered Wheelchair Manoeuvres in Mixed Reality

      Day, Thomas W.; John, Nigel W.; University of Chester (IEEE Xplore, 2019-09)
      We describe a mixed reality environment that has been designed as an aid for training driving skills for a powered wheelchair. Our motivation is to provide an improvement on a previous virtual reality wheelchair driving simulator, with a particular aim to remove any cybersickness effects. The results of a validation test are presented that involved 35 able bodied volunteers divided into three groups: mixed reality trained, virtual reality trained, and a control group. No significant differences in improvement was found between the groups but there is a notable trend that both the mixed reality and virtual reality groups improved more than the control group. Whereas the virtual reality group experienced discomfort (as measured using a simulator sickness questionnaire), the mixed reality group experienced no side effects.
    • Translational Medicine: Challenges and new orthopaedic vision (Mediouni-Model)

      Mediouni, Mohamed; Madiouni, Riadh; Gardner, Michael; Vaughan, Neil; University of Chester, UK
      Background: In North America and three European countries Translational Medicine (TM) funding has taken center stage as the National Institutes of Health (NIH), for example, has come to recognize that delays are common place in completing clinical trials based upon benchside advancements. Recently, there are several illustrative examples whereby the translation of research had untoward outcomes requiring immediate action. Methods: Focus more on three-dimensional (3D) simulation, biomarkers, and Artificial Intelligence may allow orthopaedic surgeons to predict the ideal practices before orthopaedic surgery. Using the best medical imaging techniques may improve the accuracy and precision of tumor resections. Results: This article is directed at the young surgeon scientist and in particular orthopaedic residents and all other junior physicians in training to help them better understand TM and position themselves in career paths and hospital systems that strive for optimal TM. It serves to hasten the movement of knowledge garnered from the benchside and move it quickly to the bedside. Conclusions: Communication is ongoing in a bidirectional format. It is anticipated that more and more medical Centers and institutions will adopt TM models of healthcare delivery.
    • Traversing social networks in the virtual dance hall: visualizing history in VR

      Southall, Helen; Beever, Lee; Butcher, Peter; University of Chester (IEEE Conference Publications, 2017-09-20)
      Digital recreations of historical sites and events are important tools both for academic researchers and for public interpretation. Current 3D visualization and VR technologies enable these recreations to be increasingly immersive and engaging. This poster describes a case study based on a mid-twentieth century Chester dance hall, examining the possibilities and limitations of 3D VR for recreating a public music venue which no longer physically exists, and also for visualizing and analyzing the professional network of musicians who played there, and at many other local venues.
    • The Use of Stereoscopy in a Neurosurgery Training Virtual Environment

      John, Nigel W.; Phillips, Nicholas I.; ap Cenydd, Llyr; Pop, Serban R.; Coope, David; Kamaly-Asl, Ian; de Souza, Christopher; Watt, Simon J.; University of Chester, Leeds General Infirmary, Bangor University, University of Manchester, Salford Royal NHS Foundation Trust, Cardiff University (MIT Press, 2017-03-15)
      We have previously investigated the effectiveness of a custom built virtual environment in assisting training of a ventriculostomy procedure, which is a commonly performed procedure by a neurosurgeon and a core task for trainee surgeons. The training tool (called VCath) was initially developed as a low fidelity app for a tablet platform to provide easy access and availability to trainees. Subsequently we have developed a high fidelity version of VCath that uses a stereoscopic display to immerse the trainee in the virtual environment. This paper reports on two studies that have been carried out to compare the low and high fidelity versions of VCath, particularly to assess the value of stereoscopy. Study 1 was conducted at the second annual boot camp organized for all year one trainees in neurosurgery in the UK. Study 2 was performed on lay people, with no surgical experience. Our hypothesis was that using stereoscopy in the training task would be beneficial. Results from Study 1 demonstrated that performance improved for both the control group and the group trained with the tablet version of VCath. The group trained on the high fidelity version of VCath with a stereoscopic display showed no performance improvement. The indication is that our hypothesis is false. In Study 2, six different conditions were investigated that covered the use of training with VCath on a tablet, a mono display at two different sizes, a stereo display at two different sizes, and a control group who received no training. Results from this study with lay people show that stereoscopy can make a significant improvement to the accuracy of needle placement. The possible reasons for these results and the apparent contradiction between the two studies are discussed.
    • Using and Validating Airborne Ultrasound as a Tactile Interface within Medical Training Simulators

      Hung, Gary M. Y.; John, Nigel W.; Hancock, Chris; Hoshi, Takayuki; University of Chester (Springer International Publishing, 2014-10)
      We have developed a system called UltraSendo that creates a force field in space using an array of ultrasonic transducers cooperatively emitting ultrasonic waves to a focal point. UltraSendo is the first application of this technology in the context of medical training simulators. A face validation study was carried out at a Catheter Laboratory in a major regional hospital.
    • Using Virtual Reality to Experience Different Powered Wheelchair Configurations

      Day, Thomas W.; Headleand, Christopher J.; Pop, Serban R.; John, Nigel W.; Dobson, William; University of Chester, University of Lincoln (2017-09-31)
      This paper presents recent additions to our Wheelchair-VR application, in particular the use of different drive configurations. We have previously shown that Wheelchair-VR can be used to improve driving skills. Here we consider the utility of the application in allowing users who are in the process of purchasing or upgrading a wheelchair to experience different configurations and options in a cost-effective virtual environment. A preliminary study is presented, which suggests that this approach can be effective.
    • Virtual Reality Environment for the Cognitive Rehabilitation of Stroke Patients

      John, Nigel W.; Day, Thomas W.; Pop, Serban R.; Chatterjee, Kausik; Cottrell, Katy; Buchanan, Alastair; Roberts, Jonathan; University of Chester; Countess of Chester Hospital NHS Foundation Trust; Cadscan Ltd (IEEE, 2019-10-14)
      We present ongoing work to develop a virtual reality environment for the cognitive rehabilitation of patients as a part of their recovery from a stroke. A stroke causes damage to the brain and problem solving, memory and task sequencing are commonly affected. The brain can recover to some extent, however, and stroke patients have to relearn to carry out activities of daily learning. We have created an application called VIRTUE to enable such activities to be practiced using immersive virtual reality. Gamification techniques enhance the motivation of patients such as by making the level of difficulty of a task increase over time. The design and implementation of VIRTUE is presented together with the results of a small acceptability study.
    • Visualization beyond the Desktop--the Next Big Thing

      Roberts, Jonathan C.; Ritsos, Panagiotis D.; Badam, Sriram Karthik; Brodbeck, Dominique; Kennedy, Jessie; Elmqvist, Niklas; University of Chester (IEEE, 2014-08-15)
      Visualization researchers need to develop and adapt to today’s new devices and tomorrow’s technology. Today, people interact with visual depictions through a mouse. Tomorrow, they’ll be touching, swiping, grasping, feeling, hearing, smelling, and even tasting data.
    • VRIA - A Framework for Immersive Analytics on the Web

      Butcher, Peter; John, Nigel W.; Ritsos, Panagiotis D.; University of Chester and Bangor University (ACM, 2019-05)
      We report on the design, implementation and evaluation of <VRIA>, a framework for building immersive analytics (IA) solutions inWeb-based Virtual Reality (VR), built upon WebVR, A-Frame, React and D3. The recent emergence of affordable VR interfaces have reignited the interest of researchers and developers in exploring new, immersive ways to visualize data. In particular, the use of open-standards web-based technologies for implementing VR in a browser facilitates the ubiquitous and platform-independent adoption of IA systems. Moreover, such technologies work in synergy with established visualization libraries, through the HTML document object model (DOM). We discuss high-level features of <VRIA> and present a preliminary user experience evaluation of one of our use-cases.