Paul Blenkhorn

The University of Manchester, Manchester, England, United Kingdom

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Publications (32)21.16 Total impact

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    Dataset: ICCHP2004
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    ABSTRACT: Self-management education and the issuing of a written action plan improve outcomes for asthma. Many do not receive a plan and some cannot use the written word. We have developed an electronic pictorial asthma action plan (E-PAAP). A pictorial action plan was incorporated into a software package. 21 general practices were offered this tool and the software was loaded onto 63 desktop computers (46 GPs and 17 nurses). Usage was assessed and health care professionals questioned as to its use. 190 plans had been printed in a 4-month period (17 for test purposes). The individual usage rate ranged from 0 to 28 plans. Doctors printed 73% (139/190) a mean of 3 per doctor and nurses printed 27% a mean of 2 per nurse (37/190). Excluding the test copies, 116/173(67%) were printed as picture and text together. Nearly half of all healthcare professionals used the E-PAAP software. Usage was skewed with some individuals using the software significantly more than others. The software package should help overcome problems of access to paper templates, by calculating peak flow action thresholds and by prompting correct completion. Barriers to the use of asthma action plans, such as perceived time constraints, persist. The development of an electronic asthma action plan facilitates health professional access to a basic template and prompts the user as to correct usage. It is to be hoped that such facilitation enhances the number of action plans issued and in this study GPs were greater users than the nurses.
    Patient Education and Counseling 10/2009; 80(1):141-6. · 2.60 Impact Factor
  • Paul Blenkhorn, David Gareth Evans
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    ABSTRACT: This paper presents the architecture of, and the techniques used to build, a screen magnifier for visually impaired people that uses the "high-level" features of the Microsoft Windows operating system. The magnifier uses information from the Desktop Window as its source and overlays this with a topmost, transparent, layered window that contains the magnified image. Issues concerning cursor enlargement, tooltip suppression, and focus tracking are discussed. A stable magnifier results that does not need to use the "dirty" low-level techniques that are typically used to build screen magnifiers. The only known problem of the magnifier is that it fails to suppress the original, unmagnified cursor of the few applications that use custom cursors.
    IEEE Transactions on Neural Systems and Rehabilitation Engineering 01/2007; 14(4):501-4. · 3.26 Impact Factor
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    ABSTRACT: Many domestic appliances and much office equipment is controlled using a keypad and a small digital display. Programming such devices is problematical for the blind and visually handicapped. In this paper, we describe a device that may be used to read the displays on these devices. The device is designed to accept a description of the display being read, which specifies the types and locations of elements of the display. Images are captured using a handheld webcam. Images are processed to remove the distortions due to the camera orientation. The elements of the screen are interpreted and a suitable audio output is generated. In suitably illuminated scenes, the display data is interpreted correctly in approximately 90% of the cases investigated.
    IEEE Transactions on Neural Systems and Rehabilitation Engineering 01/2007; 14(4):492-500. · 3.26 Impact Factor
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    ABSTRACT: This paper evaluates 4 commercial text-to-speech synthesisers used by dyslexic people to listen to and proof read text. Two evaluators listened to 704 common English words and determined whether the words were correctly pronounced or not. Where the evaluators agree on incorrect pronunciation, the proportion of correct pronunciations for the four synthesisers is in the range 98.9% to 99.6% of the 704 words. The evaluators also listened to the same synthesisers speaking phrases in which there were 44 pairs of homographs and determined whether each instance of the homograph was correctly spoken or not. The level of correctness for the four synthesisers ranged from 76.3% to 91.3%.
    Computers Helping People with Special Needs, 10th International Conference, ICCHP 2006, Linz, Austria, July 11-13, 2006, Proceedings; 01/2006
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    ABSTRACT: This paper investigates the use of iconicity testing to evaluate symbol ‘quality’ and to examine differences in symbol perception in different ethnic groups. The paper largely replicates an earlier study by Haupt and Alant in which a communication grid of PCS symbols was evaluated with Zulu children. In our study 10 university-educated people with long experience of Western European culture are used to test the symbols. They achieve an overall symbol correctness of 50.3% (compared with Haupt and Alant’s 18.9%) and 27.8% symbols are strictly iconic (2.8% for Haupt and Alant) and 55.6 are iconic according to a lenient criterion (11.1% for Haupt and Alant). The concept of distinctiveness as defined by Haupt and Alant is also investigated, as is a method of analyzing symbols based on frequency of selection and correctness when selected. The overall conclusion is that iconicity tests can be usefully employed for assessing symbol quality and determining the difference between ethnic groups.
    Computers Helping People with Special Needs, 10th International Conference, ICCHP 2006, Linz, Austria, July 11-13, 2006, Proceedings; 01/2006
  • D Gareth Evans, Paul Blenkhorn
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    ABSTRACT: This paper presents a set of tools that are integrated with a word processor to produce documents in a visually impaired person's "preferred format." The paper considers the motivation for producing such tools and describes tools to perform spoken transcription (to cassette tape) and intelligent large print production.
    IEEE Transactions on Neural Systems and Rehabilitation Engineering 10/2004; 12(3):325-30. · 3.26 Impact Factor
  • Paul Blenkhorn, David Gareth Evans
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    ABSTRACT: This paper presents the architecture and operation of a PC-based software program (Six-In) that allows a standard QWERTY keyboard to be used as a Braille keyboard translating the (contracted) Braille to text. It is aimed at people learning Braille and users who prefer to use a Braille rather than a QWERTY keyboard. The system is multilingual (if appropriate Braille-to-text translation tables are constructed for a language). The system works on most PCs, but fails on machines that do not support multiple key rollover.
    Computers Helping People with Special Needs, 9th International Conference, ICCHP 2004, Paris, France, July 7-9, 2004, Proceedings; 01/2004
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    ABSTRACT: The TeDUB system promises to deliver a UML diagram tool accessible to blind software engineers. The system uses a number of different interfaces and representation techniques to overcome the challenges of making diagrams created with the Unified Modeling Language usable for blind people. The system is entirely automated and does not require special preparation of UML diagrams by a sighted user. The results of evaluation of the system with thirty-six users were positive. The system was well-received and the participants were able to complete set UML tasks.
    Computers Helping People with Special Needs, 9th International Conference, ICCHP 2004, Paris, France, July 7-9, 2004, Proceedings; 01/2004
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    ABSTRACT: This paper describes the advances of the software developed in the context of the TeDUB project ("Technical Drawings Understanding for the Blind"), which aims at providing blind computer users with an accessible representation of technical diagrams. The TeDUB system consists of two separate parts: one for the (semi-) automatic analysis of images containing diagrams from a number of formally defined domains and one for the representation of previously analysed material to blind people.
    CVHI 2004; 01/2004
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    ABSTRACT: A new device, the Braille Slate Talker, is introduced. An ordinary hand held device (a PDA) is used with a fixed layout plastic guide placed over the touch screen to allow Braille input. Contracted Braille is converted to text by a table-driven state machine. Programs are written in Java language to provide full hardware and software platform independence. Future network applications will use Sun’s Jini technology.
    Computers Helping People with Special Needs, 9th International Conference, ICCHP 2004, Paris, France, July 7-9, 2004, Proceedings; 01/2004
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    ABSTRACT: This paper presents a talking word processor and a talking web browser aimed at cognitively impaired individuals. Both the word processor and the web browser can display information and text and/or symbols. EdWord provides the user with a simple word-processor in which all objects, including menu items and tool tips are spoken. Microsoft Active Accessibility (MSAA) is used to implement this level of speech access; a feature which is unusual in simple word-processors. EdWeb uses a web browser component that linearises a web page into a single linear document. This style of interface has proved successful with a range of novice web users. Both EdWord and EdWeb are freely available.
    Computers Helping People with Special Needs, 9th International Conference, ICCHP 2004, Paris, France, July 7-9, 2004, Proceedings; 01/2004
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    ABSTRACT: This paper presents the results of an investigation into tools to support blind authors in the creation and checking of word processed documents. Eighty-nine documents produced by 14 blind authors are analyzed to determine and classify common types of layout and formatting errors. Based on the survey result, two prototype tools were developed to assist blind authors in the creation of documents: a letter creation wizard, which is used before the document is produced; and a format/layout checker that detects errors and presents them to the author after the document has been created. The results of a limited evaluation of the tools by 11 blind computer users are presented. A survey of word processor usage by these users is also presented and indicates that: authors have concerns about the appearance of the documents that they produce; many blind authors fail to use word processor tools such as spell checkers, grammar checkers and templates; and a significant number of blind people rely on sighted help for document creation or checking. The paper concludes that document formatting and layout is a problem for blind authors and that tools should be able to assist.
    IEEE Transactions on Neural Systems and Rehabilitation Engineering 10/2003; 11(3):257-68. · 3.26 Impact Factor
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    ABSTRACT: Screen magnifiers are widely used by people with visual impairments. This article presents a number of architectures for screen magnifiers. It discusses a wide range of issues related to screen magnifiers and their user interfaces. A usability study of a joystick-controlled screen magnifier is then presented. Finally, the authors suggest that performing a usability evaluation with the prospective users of screen magnifiers provides a better understanding of issues related to features and control.
    IEEE Computer Graphics and Applications 08/2003; 23:54-61. · 1.23 Impact Factor
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    ABSTRACT: The study explored blind users' mental models and strategies in coping with the Windows environment and investigated the relationship between users' mental models and usability problems they face when using a screen reader. The study found that blind users possess a functional or structural mental model or a combination thereof. Blind users also have a rich and highly procedural strategy for coping with a new Windows environment and application. Users' established mental models developed from using a familiar screen reader were found to contribute to problems in using a new screen reader.
    International Journal of Rehabilitation Research 07/2003; 26(2):145-7. · 1.06 Impact Factor
  • Paul Blenkhorn, David Gareth Evans, Alex Baude
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    ABSTRACT: This paper presents the basic features of software-based magnifiers used by some visually impaired people to read information from a computer screen. The paper briefly presents two major approaches to full-screen magnification for modern multiple window systems (the paper focuses on Microsoft Windows). This paper describes in detail the architecture and operation of a full-screen magnifier that uses Microsoft DirectX Overlays. This approach leads to a robust magnifier that has a low computational overhead. The magnifier has problems with video cards that use a YUV color model but these problems may be addressed by RGB to YUV translation software--an issue that is still to be investigated. The magnifier also has problems when the generic device driver, rather than the manufacturer's device driver, is installed on the system. The paper presents two further strategies for full screen magnification, namely, using multimonitor support and true type fonts for text enlargement.
    IEEE Transactions on Neural Systems and Rehabilitation Engineering 01/2003; 10(4):225-31. · 3.26 Impact Factor
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    ABSTRACT: The paper reports on two development cycles of a joystick-operated full-screen magnifier for visually impaired users. In the first cycle of evaluation, seven visually impaired computer users evaluated the system in comprehension-based sessions using text documents. After considering feedback from these evaluators, a second version of the system was produced and evaluated by a further six visually impaired users. The second evaluation was conducted using information-seeking tasks using Web pages. In both evaluations, the 'thinking aloud protocol' was used. This study makes several contributions to the field. First, it is perhaps the first published study investigating the use of a joystick as an absolute and relative pointing device to control a screen magnifier. Second, the present study revealed that for most of the visually impaired users who participated in the study the joystick had good spatial, cognitive and ergonomic attributes, even for those who had never before used a joystick.
    Proceedings of the 2003 Conference on Human Factors in Computing Systems, CHI 2003, Ft. Lauderdale, Florida, USA, April 5-10, 2003; 01/2003
  • Gareth Evans, Paul Blenkhorn
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    ABSTRACT: This paper considers the architecture of some of the most common types of assistive software, namely, screen readers, full-screen magnifiers, on-screen keyboards, predictors and simulated Braille keyboards. The paper provides an overview of the operation of these applications and then identifies the technologies that may be used to implement assistive applications on a Windows platform. The basic architecture of each of the applications is then presented and is followed by examples of how technologies and design approaches that are used in one type of application can be used to enhance the capabilities of another type of application.
    Journal of Network and Computer Applications. 01/2003;
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    ABSTRACT: This study investigates blind users' mental models of Windows environment and their strategies in coping with new desktops and applications. The relationship between users' mental model and their perceived usability problems when using an unfamiliar screen reader is also reported. Blind users in this study possess a functional or structural mental model or a combination of thereof. They also have a rich and highly procedural strategy for coping with a new/unfamiliar Windows environment and application. Users' established mental model developed from using their familiar screen readers was found to contribute to what users perceived as usability problems when using an unfamiliar screen reader that does not work in a similar way to their familiar screen readers or does not have desired features.
    Human-Computer Interaction INTERACT '03: IFIP TC13 International Conference on Human-Computer Interaction, 1st-5th September 2003, Zurich, Switzerland; 01/2003
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    ABSTRACT: The paper reports on a usability evaluation of a full-screen magnifier. The evaluation was conducted with seven registered blind users in half-hour comprehension-based sessions using the ‘thinking aloud protocol’. The goals of the study were to determine whether joystick control of a screen magnifier was useful. The users found joystick control intuitive and easy to use. The feature with the strongest support was automatically scrolling through the text; the most significant usability problem was over-sensitivity of the joystick in certain modes.
    Universal Access: Theoretical Perspectives, Practice, and Experience, 7th ERCIM International Workshop on User Interfaces for All, Paris, France, October 24-25, 2002, Revised Papers; 01/2002