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Ross Davies

Bio: Ross Davies is an academic researcher from University of New South Wales. The author has contributed to research in topics: Stereoscopy & Cheating. The author has an hindex of 3, co-authored 11 publications receiving 31 citations.

Papers
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Proceedings ArticleDOI
01 Sep 2015
TL;DR: A novel optimisation approach for the open source Point Cloud Library that is frequently used for processing 3D data is proposed and applied in order to optimise those parts of the processing chain where measured performance is worst.
Abstract: Real-time 3D data processing is important in robotics, video games, environmental mapping, medical and many other fields. In this paper we propose a novel optimisation approach for the open source Point Cloud Library (PCL) that is frequently used for processing 3D data. Three aspects of the PCL are discussed: point cloud creation from disparity of colour image pairs, voxel grid downsample filtering to simplify point clouds and passthrough filtering to adjust the size of the point cloud. Additionally, rendering is examined. An optimisation technique based on CPU cycle measurement is proposed and applied in order to optimise those parts of the processing chain where measured performance is worst. The PCL modules thus optimised show on average an improvement in speed of 2.4x for point cloud creation, 91x for voxel grid filtering and 7.8x for the passthrough filter.

22 citations

Journal ArticleDOI
TL;DR: Digital forensics techniques were used to investigate a known case of contract cheating where the contract author has notified the university and the student subsequently confirmed that they had contracted the work out.
Abstract: Contract cheating is a major problem in Higher Education because it is very difficult to detect using traditional plagiarism detection tools. Digital forensics techniques are already used in law to determine ownership of documents, and also in criminal cases, where it is not uncommon to hide information and images within an ordinary looking document using steganography techniques. These digital forensic techniques were used to investigate a known case of contract cheating where the contract author has notified the university and the student subsequently confirmed that they had contracted the work out. Microsoft Word documents use a format known as Office Open XML Format, and as such, it is possible to review the editing process of a document. A student submission known to have been contracted out was analysed using the revision identifiers within the document, and a tool was developed to review these identifiers. Using visualisation techniques it is possible to see a pattern of editing that is inconsistent with the pattern seen in an authentic document.

11 citations

Journal ArticleDOI
01 Apr 2018
TL;DR: The algorithm presented, designed to detect people in real-time from 3D footage for use in Augmented Reality applications, is designed to be used as a first filter to extract feature points in input video frames faster than real- time.
Abstract: The algorithm presented in this paper is designed to detect people in real-time from 3D footage for use in Augmented Reality applications. Techniques are discussed that hold potential for a detection system when combined with stereoscopic video capture using the extra depth included in the footage. This information allows for the production of a robust and reliable system. To utilise stereoscopic imagery, two separate images are analysed, combined and the human region detected and extracted. The greatest benefit of this system is the second image, which contains additional information to which conventional systems do not have access, such as the depth perception in the overlapping field of view from the cameras. We describe the motivation behind using 3D footage and the technical complexity of human detection. The system is analysed for both indoor and outdoor usage, when detecting human regions. The developed system has further uses in the field of motion capture, computer gaming and augmented reality. Novelty comes from the camera not being fixed to a single point. Instead, the camera is subject to six degrees of freedom (DOF). In addition, the algorithm is designed to be used as a first filter to extract feature points in input video frames faster than real-time.

5 citations

Proceedings ArticleDOI
10 Jun 2019
TL;DR: An overview of vulnerabilities inherent in the speculative execution design of modern CPU vulnerabilities is provided and the SE Schemas of existing exploits can potentially be used in future research to identify specific attack approaches and enable scrutiny of the underlying complexity in a more organized manner.
Abstract: Speculative execution has made a significant impact in the processing speed of computing devices over the last circa 20 years. The functionality of modern CPU's to be able to ‘speculatively’ execute instructions ahead and ‘out-of-order’ of the normal process has increasingly optimized performance. However, vulnerabilities inherent in the speculative execution design are being increasingly discovered. This paper will provide an overview of some of the published works of these CPU vulnerabilities. In addition to providing an overview, this paper presents SEAM: Speculative Execution Attack Methodologies. Representing the attacks via Speculative Execution Attack Schemas (SE Attack Schemas) of the attack types provides further granularity to the attacks. The SE Schemas of existing exploits can potentially be used in future research to identify specific attack approaches and enable scrutiny of the underlying complexity in a more organized manner.

3 citations

Journal ArticleDOI
TL;DR: In this article , a prototype of a bespoke software tool that attempts to repurpose some of these techniques into an automated process for detecting plagiarism and / or contract cheating in Word documents is presented.
Abstract: Abstract Academic misconduct in all its various forms is a challenge for degree-granting institutions. Whilst text-based plagiarism can be detected using tools such as Turnitin™, Plagscan™ and Urkund™ (amongst others), contract cheating and collusion can be more difficult to detect, and even harder to prove, often falling to no more than a ‘balance of probabilities’ rather than fact. To further complicate the matter, some students will make deliberate attempts to obfuscate cheating behaviours by submitting work in Portable Document Format, in image form, or by inserting hidden glyphs or using alternative character sets which text matching software does not always accurately detect (Rogerson, Int J Educ Integr 13, 2017; Heather, Assess Eval High Educ 35:647-660, 2010). Educators do not tend to think of academic misconduct in terms of criminality per se, but the tools and techniques used by digital forensics experts in law enforcement can teach us much about how to investigate allegations of academic misconduct. The National Institute of Standards and Technology’s Glossary describes digital forensics as ‘the application of computer science and investigative procedures involving the examination of digital evidence - following proper search authority, chain of custody, validation with mathematics, use of validated tools, repeatability, reporting, and possibly expert testimony.’ (NIST, Digital Forensics, 2021). These techniques are used in criminal investigations as a means to identify the perpetrator of, or accomplices to, a crime and their associated actions. They are sometimes used in cases relating to intellectual property to establish the legitimate ownership of a variety of objects, both written and graphical, as well as in fraud and forgery (Jeong and Lee, Digit Investig 23:3-10, 2017; Fu et. al, Digit Investig 8:44–55, 2011 ). Whilst there have been some research articles and case studies that demonstrate the use of digital forensics techniques to detect academic misconduct as proof of concept, there is no evidence of their actual deployment in an academic setting. This paper will examine some of the tools and techniques that are used in law enforcement and the digital forensics field with a view to determining whether they could be repurposed for use in an academic setting. These include methods widely used to determine if a file has been tampered with that could be repurposed to identify if an image is plagiarised; file extraction techniques for examining meta data, used in criminal cases to determine authorship of documents, and tools such as FTK™ and Autopsy™ which are used to forensically examine single files as well as entire hard drives. The paper will also present a prototype of a bespoke software tool that attempts to repurpose some of these techniques into an automated process for detecting plagiarism and / or contract cheating in Word documents. Finally, this article will discuss whether these tools have a place in an academic setting and whether their use in determining if a student’s work is truly their own is ethical.

3 citations


Cited by
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Book
01 Jan 2012

160 citations

02 Feb 2012
TL;DR: This work develops a large stereo dataset with ground truth disparity maps using highly realistic computer graphic techniques and applies some of the most common stereo matching techniques to this dataset to confirm that the highly realistic CG stereo images remain as challenging as real-world stereo images.
Abstract: Stereo matching is one of the most active research areas in computer vision. While a large number of algorithms for stereo correspondence have been developed, research in some branches of the field has been constrained due to the few number of stereo datasets with ground truth disparity maps available. Having available a large dataset of stereo images with ground truth disparity maps would boost the research on new stereo matching methods, for example, methods based on machine learning. In this work we develop a large stereo dataset with ground truth disparity maps using highly realistic computer graphic techniques. We also apply some of the most common stereo matching techniques to our dataset to confirm that our highly realistic CG stereo images remain as challenging as real-world stereo images. This dataset will also be of great use for camera tracking algorithms, because we provide the exact camera position and rotation in every frame.

72 citations

Journal ArticleDOI
21 Jul 2019-Sensors
TL;DR: A three-dimensional point cloud map of a forest area was generated by using the Velodyne VLP-16 LiDAR system, so as to extract the diameter at breast height (DBH) of individual trees.
Abstract: Mobile laser scanning (MLS) is widely used in the mapping of forest environments. It has become important for extracting the parameters of forest trees using the generated environmental map. In this study, a three-dimensional point cloud map of a forest area was generated by using the Velodyne VLP-16 LiDAR system, so as to extract the diameter at breast height (DBH) of individual trees. The Velodyne VLP-16 LiDAR system and inertial measurement units (IMU) were used to construct a mobile measurement platform for generating 3D point cloud maps for forest areas. The 3D point cloud map in the forest area was processed offline, and the ground point cloud was removed by the random sample consensus (RANSAC) algorithm. The trees in the experimental area were segmented by the European clustering algorithm, and the DBH component of the tree point cloud was extracted and projected onto a 2D plane, fitting the DBH of the trees using the RANSAC algorithm in the plane. A three-dimensional point cloud map of 71 trees was generated in the experimental area, and estimated the DBH. The mean and variance of the absolute error were 0.43 cm and 0.50, respectively. The relative error of the whole was 2.27%, the corresponding variance was 15.09, and the root mean square error (RMSE) was 0.70 cm. The experimental results were good and met the requirements of forestry mapping, and the application value and significance were presented.

28 citations

Journal ArticleDOI
TL;DR: In this paper, the authors assess the current state of contract cheating research from various methodological and empi cational sources. But they do not discuss the impact of cheating in higher education.
Abstract: Contract cheating is an increasingly challenging problem facing the higher education sector. This study assesses the current state of contract cheating research from various methodological and empi...

28 citations

Proceedings ArticleDOI
20 Apr 2018
TL;DR: In this paper an approach is presented where the actual used operating area of an industrial robot gets segmented out of his whole workspace and the operating area segmented by applying an octree algorithm.
Abstract: A core challenge of human robot collaboration is to ensure safety. By renouncing guards potential hazards raise. In this paper an approach is presented where the actual used operating area of an industrial robot gets segmented out of his whole workspace. Therefore an industrial robot gets monitored with a time of flight sensor. Subsequently the recorded 3D data gets processed and the operating area segmented by applying an octree algorithm. The information thus determined about the hazard zone can be used for an application specific adjustment of safety periphery systems. This is exemplary realized by ultrasound distance sensor modules which get individually parametrized depending on the pre-segmented operating area.

19 citations