779 research outputs found
Artificial human vision
No full textCan vision be restored to the blind? As early as 1929 it was discovered that stimulating the visual cortex of an individual led to the perception of spots of light, known as phosphenes. The aim of artificial human vision systems is to attempt to utilize the perception of phosphenes to provide a useful substitute for normal vision. Currently, four locations for electrical stimulation are being investigated; behind the retina (subretinal), in front of the retina (epiretinal), the optic nerve and the visual cortex (using intra- and surface electrodes). This review discusses artificial human vision technology and requirements and reviews the current development projects
Mobility enhancement using simulated artificial human vision
No full textThe electrical stimulation of appropriate components of the human visual system can result in the perception of blobs of light (or phosphenes) in totally blind patients. By stimulating an array of closely aligned electrodes it is possible for a patient to perceive very low-resolution images from spatially aligned phosphenes. Using this approach, a number of international research groups are working toward developing multiple electrode systems (called Artificial Human Vision (AHV) systems or visual prostheses) to provide a phosphene-based substitute for normal human vision. Despite the great promise, there are currently a number of constraints with current AHV systems. These include limitations in the number of electrodes which can be implanted and the perceived spatial layout and display frequency of phosphenes. Therefore the development of computer vision techniques that can maximise the visualisation value of the limited number of phosphenes would be useful in compensating for these constraints. The lack of an objective method for comparing different AHV system displays, in addition to comparing AHV systems and other blind mobility aids (such as the long cane), has been a significant problem for AHV researchers. Finally, AHV research in Australia and many other countries relies strongly on theoretical models and animal experimentation due to the difficult of prototype human trials. Because of this constraint the experiments conducted in this thesis were limited to simulated AHV devices with normally sighted research participants and the true impact on blind people can only be regarded as approximated. In light of these constraints, this thesis has two general aims. The first aim is to investigate, evaluate and develop effective techniques for mobility assessment which will allow the objective comparison of different AHV system phosphene presentation methods. The second aim is to develop a useful display framework to guide the development of AHV information presentation, and use this framework to guide the development of an AHV simulation device. The first research contribution resulting from this work is a conceptual framework based on literature reviews of blind and low vision mobility, AHV technology, and computer vision. This framework incorporates a comprehensive number of factors which affect the effectiveness of information presentation in an AHV system. Experiments reported in this thesis have investigated a number of these factors using simulated AHV with human participants. It has been found that higher spatial resolution is associated with accurate walking (reduced veering), whereas higher display rate is associated with faster walking speeds. In this way it has been demonstrated that the conceptual framework supports and guides the development of an adaptive AHV system, with the dynamic adjustment of display properties in real-time. The second research contribution addresses mobility assessment which has been identified as an important issue in the AHV literature. This thesis presents the adaptation of a mobility assessment method from the blind and low vision literature to measure simulated AHV mobility performance using real-time computer based analysis. This method of mobility assessment (based on parameters for walking speed, obstacle contacts and veering) is demonstrated experimentally in two different indoor mobility courses. These experiments involved sixty-five participants wearing a head-mounted simulation device. The final research contribution in this thesis is the development and evaluation of an original real-time looming obstacle detector, based on coarse optical flow, and implemented on a Windows PocketPC based Personal Digital Assistant (PDA) using a CF card camera. PDA based processors are a preferred main processing platform for AHV systems due to their small size, light weight and ease of software development. However, PDA devices are currently constrained by restricted random access memory, lack of a floating point unit and slow internal bus speeds. Therefore any real-time software needs to maximise the use of integer calculations and minimise memory usage. This contribution was significant as the resulting device provided a selection of experimental results and subjective opinions
Soil properties at 1 m resolution for ILRI Kapiti, Version 1.0
No full textThe dataset includes soil maps at 1-m resolution for the International Livestock Research Institute (ILRI) Kapiti Wildlife Conservancy and Kapiti Research Station, covering 12,959 ha in Machakos County, Kenya. The dataset provides high-quality images (extension .tif; tiff images) and spatial data (extensions .tif and .ovr; geotiff) for most major soil properties (fractional soil texture, pH, and stocks of C, N, and P in g m-2, adjusted for soil bulk density) at four depths (0-5, 5-20, 20-50, and 50-100 cm) at the 1-m resolution of a digital elevation model (DEM) (Dowling 2019). The maps for Version 1.0 are from simple spatial kriging as a function of elevation, based on an initial set of 65 triple-bulked soil samples taken from randomized locations stratified by elevation.
Dowling, T 2019, Kapiti research farm and ranch map 3. King's College London. https://doi.org/10.18742/pub01-00
John Everett Millais
No full textJohn Everett Millais was one of the most successful and acclaimed British painters of the nineteenth century. A founder member of the radical Pre-Raphaelite Brotherhood, an acclaimed society portraitist, and an ambitious painter of historical themes, Millais ended his days as a Baronet and President of the Royal Academy. In this widely illustrated, thoughtful account of Millais’s career, Jason Rosenfeld brings together biography, art history and an insightful and detailed analysis of individual paintings. Opening with a focused study of his much acclaimed, and now iconic Pre-Raphaelite paintings, in the second half of the book the author presents a fascinating reconsideration of the artist’s often over looked later career.</p
John Everett Millais
No full textJohn Everett Millais was one of the most successful and acclaimed British painters of the nineteenth century. A founder member of the radical Pre-Raphaelite Brotherhood, an acclaimed society portraitist, and an ambitious painter of historical themes, Millais ended his days as a Baronet and President of the Royal Academy. In this widely illustrated, thoughtful account of Millais’s career, Jason Rosenfeld brings together biography, art history and an insightful and detailed analysis of individual paintings. Opening with a focused study of his much acclaimed, and now iconic Pre-Raphaelite paintings, in the second half of the book the author presents a fascinating reconsideration of the artist’s often over looked later career.</p
James Sheen Dowling
No full text<p>James Sheen Dowling was born on 2 December 1819 in London, England. He arrived in Sydney on 24 February 1828 on the 'Hooghly' with his parents, Sir James and Maria Dowling, where his father was to take up a position as puisne judge of the Supreme Court of New South Wales. James Sheen Dowling was educated under John Dunmore Lang, Joseph Docker, William Cape, at the Sydney College, and after returning to England in 1836, at King's College, London (LLB 1841). Admitted to the Middle Temple in 1840, he was called to the Bar on 24 November 1843. He gained experience in common law, equity pleading and conveyancing and worked for his uncle, Alfred Septimus Dowling at the 'Legal Observer and Solicitor's Journal'. Following his father's death, he returned to Sydney in September 1845. (1)<br /><br />He was admitted to the New South Wales Bar on 20 October 1845. In 1846 he was appointed acting Judge-Advocate to the new penal colony to be called 'North Australia', at or near what is now Gladstone, Queensland. After the settlement failed, he returned to Sydney where he continued his practice at the Bar and reported for the Sydney Morning Herald. On 1 January 1851, he was appointed Police Magistrate of the City of Sydney, a position he was to occupy until 11 February 1857. It also included the duties of Visiting Magistrate to Darlinghurst Gaol from 10 November 1856. He was appointed Crown Prosecutor for the Court of Quarter Sessions at Sydney on 12 February 1857. (2)<br /><br />On 1 January 1859 he was appointed District Court Judge for the Western Police District and Chairman of Quarter Sessions, Western District, an area that included Bathurst, Carcoar, Dubbo, Hartley, Molong, Mudgee, and Orange. On 1 October 1861 he was made one of the two District Court Judges for the Metropolitan and Coast Police District and Chairman of Quarter Sessions, Cumberland and Coast District. Metropolitan and Coast District initially included Sydney to Penrith and Windsor, and the South Coast to Eden. In 1866 it expanded to take in the Hunter Region but in 1870 it shed the South Coast area. In 1878 it was renamed the Metropolitan and Hunter District. In 1865, following Alfred Cheeke's rise to the Supreme Court, Dowling became Senior District Court Judge Metropolitan and Coast District. In 1867 he was allowed 12 months leave of absence on half salary from 7 January 1867 to 16 January 1868. Whilst acting for Judge Henry Ralph Francis at Young in 1874, he suffered a serious coach accident near Binalong. He was on leave from 1 February to 30 April and 1 to 30 June. The accident left him with long term impairment. (3) By April 1878 Dowling was occasionally acting as a Supreme Court Judge, a role he appears to have continued in the 1880s. Dowling tendered his resignation in February 1889 due to ill health but was persuaded to take leave from 1 March 1889 to 30 June, when he visited Europe. He eventually retired on 31 July 1889 on a pension and died at his home in Woollahra on 4 May 1902. (4)<br /><br />Endnotes<br />1. A R Dowling, 'Dowling, James Sheen (1819-1902)', Australian Dictionary of Biography, Online edition, <a href="http://www.adb.online.anu.edu/biogs/A040093b.htm%20cited%2011%20January%202008">http://www.adb.online.anu.edu/biogs/A040093b.htm</a> cited 11 January 2008; HTE Holt, 'James Sheen Dowling' in A Court Rises: the lives and times of the Judges of the District Court of New South Wales (1859-1959), North Sydney, Law Foundation of New South Wales, 1976, p.27-33; Fred Johns, Johns's Notable Australians and Who's Who in Australasia, Adelaide, the Author, 1908, p.344; 'Dowling, James Sheen (1819-1902)', Australian Encyclopaedia, Sydney, Angus and Robertson, 1958, p.277; The Jurist, 9 December 1843, p.436, at Google Book Search <a href="http://books.google.com/books?id=G0cwAAAAIAAJ&printsec=titlepage#PPA436,M">http://books.google.com/books?id=G0cwAAAAIAAJ&printsec=titlepage#PPA436,M</a> cited 21 February 2008; Obituary Daily Telegraph 5 May 1902 as cited in 'The Death of ex-Judge Dowling', Forbes Flyer, Winter 2007, Issue 16, p.3 <a href="http://www.forbessociety.org.au/Publications/FFlyer/documents/winter.pdf"><font color="#800080">http://www.forbessociety.org.au/Publications/FFlyer/documents/winter.pdf</font></a> cited 1 February 2008.<br />2. Supreme Court; NRS 13664, Roll of Barristers and Solicitors, 1824-1876; SR Fiche 852, p.4A; HTE Holt, op.cit, p.29-33; Colonial Secretary; NRS 1286, Returns of the Colony (Blue Books); 1851, p.360; 1856, pp.368, 428; 1857, pp.298, 458; New South Wales Government Gazette No.1, 3 January 1851, p.2; No.170, 11 November 1856, p.2891; No.21, 13 February 1857, p.263.<br />3. HTE Holt, op.cit., Public Service Lists (Blue Books), 1859, p.73; 1861, pp.87, 89; 1865, pp.40, 42; 1866, p.40, 42; 1867, p.40, 48; 1868, p.40, 42; 1870, p.44; 1874, p.42; 1878, p.52; NSW Government Gazette No.214, 22 December 1858, p.2253; No.179, 25 July 1861, p.1593; No.261, 16 December 1865, p.2833; No.296, 25 September, 1878, p.3835.<br />4. HTE Holt, op.cit., NSW Government Gazettes No. 88, 28 March 1878, p.1247; No.342, 23 September 1879, p.4213; No.113, 31 March 1880, p.1509; No.378, 24 September 1880, p.5005; No.112, 25 March 1881, pp.1623-4; No. 144, 8 April 1881, p.2041; No.382, 30 September 1881, p.5000; Public Service Lists (Blue Books), 1889, pp.97, 118.</p>PER-186Acting Judge Advocate North Australia 01/01/1846-31/12/1846<br/>Police Magistrate, Sydney Court of General and Quarter Sessions 01/01/1851-11/02/1857<br/>Crown Prosecutor, Sydney Court of General and Quarter Sessions 12/02/1857-31/12/1858<br/>District Court Judge, Western Police District 01/01/1859-30/09/1861<br/>Chairman, Western Police District Quarter Sessions 01/01/1859-30/09/1861<br/>District Court Judge, Metropolitan and Coast Police District 01/10/1861-31/07/1889<br/>Chairman of Quarter Sessions, Cumberland and Coast District 01/10/1861-31/07/1889<br/>Acting Judge, Supreme Court of New South Wales 01/04/1878-31/12/1881 ?<br/>
Fantasmi a Palazzo Lanfranchi e porcellini d'India a Bagni di Pisa: appunti su Byron, Shelley e il primo "gran commento" di Dante in inglese
No full textAn examination of Shelley and Byron's interest in Dante as a poet and patriot and of their relations with Irish expatriate John Taaffe, author of the first English-language commentary on the Divine Comedy (1821)
Simulated Artificial Human Vision: The Effects of Spatial Resolution and Frame Rate on Mobility
No full textThe publication is available at IOS Press through http://ebooks.iospress.nl/volumearticle/2521
Reproduced with permission from IOS Press www.iospress.nlElectrical stimulation of the human visual system can result in the perception of blobs of light, known as phosphenes. Artificial Human Vision (AHV or visual prosthesis) systems use this method to provide a visual substitute for the blind. This paper reports on our experiments involving normally sighted participants using a portable AHV simulation. A Virtual Reality Head Mounted Display is used to display the phosphene simulation. Custom software converts captured images from a head mounted USB camera to a DirectX based phosphene simulation. The effects of frame rate (1, 2 and 4 FPS) and phosphene spatial resolution (16x12 and 32x24) on participant Percentage of Preferred Walking Speed (PPWS) and mobility errors were assessed during repeated trials on an artificial indoor mobility course. Results indicate that spatial resolution is a significant factor in reducing contact with obstacles and following a path without veering, however the phosphene display frame rate is a better predictor of a person’s preferred walking speed. These findings support the development of an adaptive display which could provide a faster display with reduced spatial resolution when a person is walking comfortably and a slower display with higher resolution when a person has stopped moving
Mobility enhancement and assessment for a visual prosthesis
No full textThis paper investigates methods of processing mobility related static images to enhance the effectiveness of a visual prosthesis system. Eight images were processed into 50x50 pixel binary, greyscale, Sobel and Canny edge detected images. 10 subjects were asked 5 mobility related identification tasks for each (randomly ordered) image. Results indicate that edge detection may be useful at this resolution. However, there was not a significant difference found between the results achieved using the Canny and Sobel algorithms. These results support the development of an adaptive device. A mobility display framework has been proposed to assist in this development. Future work will focus on processing image sequences and the development of a visual prosthesis simulation device
Intelligent image processing constraints for blind mobility facilitated through artificial vision
No full textThis paper examines intelligent image processing constraints which may need to be considered for visual prosthesis development and proposes a display framework which incorporates context, task and alerts related to a scene. A simulation device to investigate this framework is also described. Mobility requirements, assessment, and devices are discussed to identify the functions required by a prosthesis, and an overview of state of the art visual prostheses is provided. Two main computer vision approaches are discussed with application to a visual prosthesis: information reduction and scene understanding
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