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A Review of Hashing based Image Copy Detection Techniques
Get PDFImages are considered to be natural carriers of information, and a large number of images are created, exchanged and are made available online. Apart from creating new images, the availability of number of duplicate copies of images is a critical problem. Hashing based image copy detection techniques are a promising alternative to address this problem. In this approach, a hash is constructed by using a set of unique features extracted from the image for identification. This article provides a comprehensive review of the state-of-the-art image hashing techniques. The reviewed techniques are categorized by the mechanism used and compared across a set of functional & performance parameters. The article finally highlights the current issues faced by such systems and possible future directions to motivate further research work
Automated Biometric Authentication with Cloud Computing
Get PDFThe convenience provided by cloud computing has led to an increasing trend of many business organizations, government agencies and individual customers to migrate their services and data into cloud environments. However, once clients’ data is migrated, the overall security control will be immedicably shifted form data owners to the hand of cloud service providers. In fact, most cloud clients do not even know where their data is physically stored, and therefore the question of how to limit data access to authorized users has been one of the biggest challenges in cloud environments. Although security tokens and passwords are widely used form of remote user authentication, they can be lost or stolen as they are not linked with the identity of data owner. Therefore, biometric based authentication can potentially offer a practical and reliable option for remote access control. This chapter starts with a brief introduction that covers the fundamental concepts of cloud computing and biometric based authentication. It then provides and in-depth discussions on authentication challenges for the cloud computing environment and the limitation of traditional solutions. This leads to the key sections related to biometric solutions for cloud computing in which we present state-of-art approaches that offer convenient and privacy-preserving authentication needed for cloud environment. The chapter argues that addressing privacy concerns surrounding the use of biometrics in cloud computing is one of the key challenges that has to be an integral part of any viable solution for any biometric-based authentication. It also argues that assuring cloud clients that their biometric templates will not be used without their permission to, for example, track them is not enough. Such solutions should make it technically infeasible to do so even if a cloud service provider wants to. This chapter explains a number of interesting solutions that have been recently proposed to improve security and, at the same time, maintain user privacy. Finally, we identify some challenges that still need to be addressed and highlight relevant Research Directions
An Exploration of ‘Fitspiration’ content on YouTube and its impacts on consumers
Get PDFThe ‘Fitspiration’ movement may endorse problematic body image and behaviour. This study aims to expand the understanding of ‘fitspiration’ by examining its presence on YouTube. Analysis was conducted in accordance with Tiggeman & Zaccardo (2015) and Santarossa et al. (2016). Thematic analysis of videos revealed three themes; ‘Fitness and beauty’, ‘Trust me-I’m a YouTuber’, and ‘Health for the right reasons’. Thematic analysis of comments revealed themes ‘YouTube fitness community’, ‘Body appearance dissatisfaction,’ and ‘YouTuber fitness role models’. Fitness YouTubers were found to promote unhealthy behaviours to achieve fitness, and commenters expressed belief in and replication of their advice
Evaluating Mental Health Literacy in Medical Students in the United Kingdom
Get PDFThere is urgent need to explore medical students’ understandings of mental illness to better support this high-risk group. This study aimed to evaluate mental health literacy in medical students using the Mental Health Literacy Scale (MHLS) and provide validation of the measure. 251 participants were recruited from medical schools across the U.K. Participants completed demographic details and the MHLS. This paper reports total MHLS scores and their relationships with demographics and experiences with mental illness. The mean MHLS score was 127.69. MHL was significantly higher in females, and students in later years of study (p < .05). Over 40% of respondents reported having personal experience of mental illness. This, as well as having a close friend or family member with a mental illness, was associated with higher MHL (p < .05). This study presents the first to use the MHLS and provide validation of this measure in medical students. Despite high rates of personal experience with mental health issues, medical students’ average MHLS scores were comparable to studies of non-medical student groups. Medical schools should aim to build students’ confidence in recognizing and seeking help for mental health issues from the first year of medical training. MHL is a multifaceted issue; further work is required to improve awareness of risk factors, to better understand why males demonstrate poorer MHL scores than females, and to work towards improving MHL in males
Toric geometry of G2-manifolds
Get PDFWe consider G2-manifolds with an effective torus action that is multi-Hamiltonian for one or more of the defining forms. The case of T3-actions is found to be distinguished. For such actions multi-Hamiltonian with respect to both the three- and four-form, we derive a Gibbons-Hawking type ansatz giving the geometry on an open dense set in terms a symmetric 3×3-matrix of functions. This leads to particularly simple examples of explicit metrics with holonomy equal to G2. We prove that the multi-moment maps exhibit the full orbit space topologically as a smooth four-manifold containing a trivalent graph as the image of the set of special orbits and describe these graphs in some complete examples
Improving embedding efficiency for digital steganography by exploiting similarities between secret and cover images
No full textDigital steganography is becoming a common tool for protecting sensitive communications in various applications such as crime/terrorism prevention whereby law enforcing personals need to remotely compare facial images captured at the scene of crime with faces databases of known criminals/suspects; exchanging military maps or surveillance video in hostile environment/situations; privacy preserving in the healthcare systems when storing or exchanging patient’s medical images/records; and prevent bank customers’ accounts/records from being accessed illegally by unauthorized users. Existing digital steganography schemes for embedding secret images in cover image files tend not to exploit various redundancies in the secret image bit-stream to deal with the various conflicting requirements on embedding capacity, stego-image quality, and undetectibility. This paper is concerned with the development of innovative image procedures and data hiding schemes that exploit, as well as increase,similarities between secret image bit-stream and the cover image LSB plane. This will be achieved in two novel steps involving manipulating both the secret and the cover images, prior
to embedding, to achieve higher 0:1 ratio in both the secret image bit-stream and the cover image LSB plane. The above two steps strategy has been exploited to use a bit-plane(s)
mapping technique, instead of bit -plane(s) replacement to make each cover pixel usable for secret embedding. This paper will demonstrate that this strategy produces stego-images that have minimal distortion, high embedding efficiency, reasonably good stego-image quality and robustness against 3 well-known targeted steganalysis tools
THE RISE OF A STRATEGIC SPOILER: RUSSIA’S EUROPEAN SECURITY STRATEGY
Get PDFRussia’s annexation of Crimea in March 2014 was the latest step in Moscow’s steadfast rejection of the post-Cold War security order in Europe. Nevertheless, analysts and scholars remain puzzled as to what exactly constitutes Russia’s long-term game plan vis-à-vis Europe. This chapter suggests that, far from following a concrete, well-planned blueprint at the operational and tactical levels, Russia’s grand strategic objectives enable Moscow to adopt a fluid, adaptive posture aiming at achieving two interconnected goals: to maintain, or even improve, the continental military balance of power through the deployment of strategic weapons and at the same time acquire the capabilities to disrupt NATO’s air and naval superiority in critical flashpoints, an aspiration that had been elusive even at the peak of the Cold War rivalry. The implications of Russia’s grand strategic doctrine are thus crucial for Europe’s security outlook; Moscow’s approach implies that Russian deterrence at the highest levels will be robust, while low-level, disruptive tactics in areas where Russia maintains an operational advantage could challenge the European security status quo. Contemporary developments, therefore, may enable Russia to undermine NATO’s supremacy in the Euro-Atlantic geopolitical space, altering the post-Cold War order
Clinical prioritisation questions: A novel assessment tool to encourage tolerance of uncertainty?
Get PDFUncertainty is a common and increasingly acknowledged problem in clinical practice. Current single best answer (SBA) style assessments test areas where there is one correct answer, and as the approach to assessment impacts on the approach to learning, these exams may poorly prepare our future doctors to handle uncertainty. We therefore, need to modify our approach to assessment to emphasize reasoning and introduce the possibility of more than one ‘correct’ answer. We have developed clinical prioritization questions (CPQs), a novel formative assessment tool in which students prioritize possible responses in order of likelihood. This assessment format was piloted with a group of medical students and evaluated in comparison with the more traditional SBA question format in a team-based learning setting. Students reported that they felt ongoing use would help improve their tolerance of uncertainty (p < 0.01). Furthermore, over 80% of students felt that CPQs were more reflective of real-life clinical practice. Group based discussions were significantly longer when answering CPQs (p < 0.01), suggesting they may promote richer discourse. CPQs may have a role in formative assessment to help equip students with the skills to cope with ambiguity and strengthen clinical reasoning and decision-making. Institutions may find them more practical to implement compared with other clinical reasoning assessment tools
Oxygen — A Critical, but Overlooked, Nutrient
Get PDFGaseous oxygen is essential for all aerobic animals, without which mitochondrial respiration and oxidative phosphorylation cannot take place. It is not, however, regarded as a “nutrient” by nutritionists and does not feature as such within the discipline of nutritional science. This is primarily a consequence of the route by which O2 enters the body, which is via the nose and lungs in terrestrial animals as opposed to the mouth and gastrointestinal tract for what are customarily considered as nutrients. It is argued that the route of entry should not be the critical factor in defining whether a substance is, or is not, a nutrient. Indeed, O2 unambiguously meets the standard dictionary definitions of a nutrient, such as “a substance that provides nourishment for the maintenance of life and for growth” (Oxford English Dictionary). O2 is generally available in abundance, but deficiency occurs at high altitude and during deep sea dives, as well as in lung diseases. These impact on the provision at a whole-body level, but a low pO2 is characteristic of specific tissues includings the retina and brain, while deficiency, or overt hypoxia, is evident in certain conditions such as ischaemic disease and in tumours - and in white adipose tissue in obesity. Hypoxia results in a switch from oxidative metabolism to increased glucose utilisation through anaerobic glycolysis, and there are extensive changes in the expression of multiple genes in O2-deficient cells. These changes are driven by hypoxia-sensitive transcription factors, particularly hypoxia-inducible factor-1 (HIF-1). O2 deficiency at a whole-body level can be treated by therapy or supplementation, but O2 is also toxic through the generation of reactive oxygen species. It is concluded that O2 is a critical, but overlooked, nutrient which should be considered as part of the landscape of nutritional science