Beth Filar Williams
Full Text Available Open Educational Resources (OER are increasingly used in the higher education landscape as a solution for a variety of copyright, publishing and cost-prohibiting issues. While OERs are becoming more common, reports of usability tests that evaluate how well learners can use them to accomplish their learning tasks have lagged behind. Because both the researchers and the learners in this study use resources and tools remotely, asynchronous usability testing of a prototype OER and MOOC online guide was conducted with an exploratory group of users to determine the guide’s ease of use for two distinct groups of users: Educators and Learners. In this article, we share the background and context of this usability project, suggest best methods for asynchronous remote usability testing, and share challenges and insights of the process and results of the testing
Lizano, Fulvio; Stage, Jan
Remote Usability Testing (RUT) is an alternative method of usability evaluations. The main aim of RUT is the reduction of costs in the usability evaluation process. Since middle of the 90s RUT, has emerged as a technique which seems as is gaining maturity across the time. In general any discipline...
Stage, Jan; Andreasen, M. S.; Nielsen, H. V.
The idea of conducting usability tests remotely emerged ten years ago. Since then, it has been studied empirically, and some software organizations employ remote methods. Yet there are still few comparisons involving more than one remote method. This paper presents results from a systematic...... empirical comparison of three methods for remote usability testing and a conventional laboratorybased think-aloud method. The three remote methods are a remote synchronous condition, where testing is conducted in real time but the test monitor is separated spatially from the test subjects, and two remote...
Kayode Peter Ayodele; Lawrence O. Kehinde; Olusola A. Komolafe
One of few limitations of remote laboratory technology is the fact that access and usability of such laboratories depend largely on the existence of favorable bandwidth conditions between the remote user and the system under test. This dependence is regrettable because some of the institutions likely to find remote laboratories attractive are also those most likely to have severe bandwidth limitations. Also, a typical remote laboratory will be completely unusable to remote students in the eve...
Wozney, Lori M; Baxter, Pamela; Fast, Hilary; Cleghorn, Laura; Hundert, Amos S; Newton, Amanda S
Research in the fields of human performance technology and human computer interaction are challenging the traditional macro focus of usability testing arguing for methods that help test moderators assess "use in context" (ie, cognitive skills, usability understood over time) and in authentic "real world" settings. Human factors in these complex test scenarios may impact on the quality of usability results being derived yet there is a lack of research detailing moderator experiences in these test environments. Most comparative research has focused on the impact of the physical environment on results, and rarely on how the sociotechnical elements of the test environment affect moderator and test user performance. Improving our understanding of moderator roles and experiences with conducting "real world" usability testing can lead to improved techniques and strategies To understand moderator experiences of using Web-conferencing software to conduct remote usability testing of 2 eHealth interventions. An exploratory case study approach was used to study 4 moderators' experiences using Blackboard Collaborate for remote testing sessions of 2 different eHealth interventions. Data collection involved audio-recording iterative cycles of test sessions, collecting summary notes taken by moderators, and conducting 2 90-minute focus groups via teleconference. A direct content analysis with an inductive coding approach was used to explore personal accounts, assess the credibility of data interpretation, and generate consensus on the thematic structure of the results. Following the convergence of data from the various sources, 3 major themes were identified: (1) moderators experienced and adapted to unpredictable changes in cognitive load during testing; (2) moderators experienced challenges in creating and sustaining social presence and untangling dialogue; and (3) moderators experienced diverse technical demands, but were able to collaboratively troubleshoot with test users
Chalil Madathil, Kapil; Greenstein, Joel S
Collaborative virtual reality-based systems have integrated high fidelity voice-based communication, immersive audio and screen-sharing tools into virtual environments. Such three-dimensional collaborative virtual environments can mirror the collaboration among usability test participants and facilitators when they are physically collocated, potentially enabling moderated usability tests to be conducted effectively when the facilitator and participant are located in different places. We developed a virtual collaborative three-dimensional remote moderated usability testing laboratory and employed it in a controlled study to evaluate the effectiveness of moderated usability testing in a collaborative virtual reality-based environment with two other moderated usability testing methods: the traditional lab approach and Cisco WebEx, a web-based conferencing and screen sharing approach. Using a mixed methods experimental design, 36 test participants and 12 test facilitators were asked to complete representative tasks on a simulated online shopping website. The dependent variables included the time taken to complete the tasks; the usability defects identified and their severity; and the subjective ratings on the workload index, presence and satisfaction questionnaires. Remote moderated usability testing methodology using a collaborative virtual reality system performed similarly in terms of the total number of defects identified, the number of high severity defects identified and the time taken to complete the tasks with the other two methodologies. The overall workload experienced by the test participants and facilitators was the least with the traditional lab condition. No significant differences were identified for the workload experienced with the virtual reality and the WebEx conditions. However, test participants experienced greater involvement and a more immersive experience in the virtual environment than in the WebEx condition. The ratings for the virtual
Kayode Peter Ayodele
Full Text Available One of few limitations of remote laboratory technology is the fact that access and usability of such laboratories depend largely on the existence of favorable bandwidth conditions between the remote user and the system under test. This dependence is regrettable because some of the institutions likely to find remote laboratories attractive are also those most likely to have severe bandwidth limitations. Also, a typical remote laboratory will be completely unusable to remote students in the event of an outright network downtime. In this paper, we propose a hybrid online laboratory architecture that allows the automatic generation of accurate software models of remote laboratories. Such models can be hosted closer to the student and during periods of unfavorable bandwidth conditions, students can successfully interact with such models in lieu of the real hardware. We identify the challenges that need to be resolved for such a scheme to be useful and discuss the process by which suitable modeling bases were chosen. Finally we present and discuss data from a first test of the system and conclude that such a scheme holds considerable promise in changing the way remote laboratories are used and viewed.
Lewis, Jeffrey A; Deutsch, Judith E; Burdea, Grigore
The Remote Console (ReCon) is a telerehabilitation application that allows therapists to remotely communicate with patients while monitoring and controlling their virtual rehabilitation exercises. It provides therapists visual feedback of patients' movements, their exercise simulations replicated in real time and with tools to conduct training without a face-to-face session. The Recon underwent a formative evaluation (a type of usability engineering methodology) used to refine its design. Five physical therapists from different practice settings acted as representative users. During the evaluation, these users made errors related to manipulation and finding and understanding controls. Technical issues with the server and audio communication were identified. These findings were used to fine-tune the ReCon system.
Geller, Gary N.
Although remote sensing data are now widely available, much of it at low or no-cost, many managers of protected conservation areas do not have the expertise or tools to view or analyze it. Thus access to it by the protected area management community is effectively blocked. The Protected Area Archive will increase access to remote sensing data by creating collections of satellite images of protected areas and packaging them with simple-to-use visualization and analytical tools. The user can easily locate the area and image of interest on a map, then display, roam, and zoom the image. A set of simple tools will be provided so the user can explore the data and employ it to assist in management and monitoring of their area. The 'Phase 1 ' version requires only a Windows-based computer and basic computer skills, and may be of particular help to protected area managers in developing countries.
E. S. Kudryashova
Full Text Available The paper consider a mathematical model of a concurrent system, the special case of which is an asynchronous system. Distributed asynchronous automata are introduced here. It is proved that Petri nets and transition systems with independence can be considered as distributed asynchronous automata. Time distributed asynchronous automata are defined in a standard way by correspondence which relates events with time intervals. It is proved that the time distributed asynchronous automata generalize time Petri nets and asynchronous systems.
Annie Jane Hill
Full Text Available Asynchronous telerehabilitation in which computer-based interventions are remotely monitored and adapted offline is an emerging service delivery model in the rehabilitation of communication disorders. The asynchronous nature of this model may hold a benefit over its synchronous counterpart by eliminating scheduling issues and thus improving efficiency in a healthcare landscape of constrained resource allocation. The design of asynchronous telerehabilitation platforms should therefore ensure efficiency and flexibility. The authors have been engaged in a program of research to develop and evaluate an asynchronous telerehabilitation platform for use in speech-language pathology. eSALT is a novel asynchronous telerehabilitation platform in which clinicians design and individualize therapy tasks for upload to a client’s mobile device. An inbuilt telerehabilitation module allows for remote monitoring and updating of tasks. This paper introduces eSALT and reports outcomes from an usability study that considered the needs of two end-user groups, people with aphasia and clinicians, in the on-going refinement of eSALT. In the study participants with aphasia were paired with clinicians who used eSALT to design and customize therapy tasks. After training on the mobile device the participants engaged in therapy at home for a period of three weeks, while clinicians remotely monitored and updated tasks. Following the home trial, participants and clinicians engaged in semi-structured interviews and completed surveys on the usability of eSALT and their satisfaction with the platform. Content analysis of data involving five participants and three clinicians revealed a number of usability themes including ease of use, user support, satisfaction, limitations and potential improvements. These findings were translated into a number of refinements of the eSALT platform including the development of a client interface for use on the Apple iPad®, greater variety in
Hertzum, Morten; Clemmesen, Torkil; Hornbæk, Kasper Anders Søren
Whereas research on usability predominantly employs universal definitions of the aspects that comprise usability, people experience their use of information systems through personal constructs. Based on 48 repertory-grid interviews, this study investigates how such personal constructs are affected...... use of constructs traditionally associated with usability (e.g., easy-to-use, intuitive, and liked). Further analysis of the data is ongoing...
The concept of usability has become an increasingly important consideration in the design of all kinds of technology. As more products are aimed at global markets and developed through internationally distributed teams, usability design needs to be addressed in global terms. Interest in usability as a design issue and specialist area of research and education has developed steadily in North America and Europe since the 1980's. However, it is only over the last ten years that it has emerged as a global concern. Global Usability provides an introduction to the important issues in globalizing des
Culture has already played an important role in the global market. It not only affects products, but also impacts on usability evaluation methods. This project aims to examine in the established thinking aloud usability evaluation method (TA UEM), how does the evaluator build a supportive...
Nørgaard, Mie; Høegh, Rune T.
Usability evaluation is widely accepted as a valuable activity in software development. However, how results effectively are fed back to developers is still a relatively unexplored area. We argue that usability feedback can be understood as an argument for a series of usability problems......, and that basic concepts from argumentation theory can help us understand how to create persuasive feedback. We revisit two field studies on usability feedback to study if concepts from Toulmin's model for argumentation and Aristotle's modes of persuasion can explain why some feedback formats outperform others....... We recommend that evaluators specifically back up the warrants behind their usability claims, that their arguments use several modes of persuasion, and that they present feedback in browsable amounts not to overwhelm developers with information. For complex and controversial problems, we advise...
Bergmans, J.W.M.; Lin, M.Y.; Modrie, D.; Otte, R.
Digital data receivers often operate at a fixed sampling rate 1/Ts that is asynchronous to the baud rate 1/T. A digital equalizer that processes the incoming signal will also operate in the asynchronous clock domain. Existing adaptation techniques for this equalizer involve an error sequence ek that
Aryana, Bijan; Clemmensen, Torkil
In this article, a country specific comparative mobile usability study is presented, using Iran and Turkey as the two chosen emerging/emergent nation exemplars of smartphone usage and adoption. In a focus group study, three mobile applications were selected by first-time users of smartphones...... personal contacts. The results and analysis establish the existence of country specific issues and concerns, as well as reveal generic usability issues. The article concludes that the source of these issues is most likely due to a combination of certain contextual features endemic to both Iran and Turkey...
Full Text Available The production of the electric energy with lower costs could be realized with the help of the aeolian electric central. In these centrals we can use the squirrel cage asynchronous generators, because these machines are the most safety in function and easy exploited. This work show the function analyzing of the asynchronous generator having on involving torque depending on the square wind speed, the air-density and on the construction of the wing spiral.
In one form, a logic circuit includes an asynchronous logic circuit, a synchronous logic circuit, and an interface circuit coupled between the asynchronous logic circuit and the synchronous logic circuit. The asynchronous logic circuit has a plurality of asynchronous outputs for providing a corresponding plurality of asynchronous signals. The synchronous logic circuit has a plurality of synchronous inputs corresponding to the plurality of asynchronous outputs, a stretch input for receiving a stretch signal, and a clock output for providing a clock signal. The synchronous logic circuit provides the clock signal as a periodic signal but prolongs a predetermined state of the clock signal while the stretch signal is active. The asynchronous interface detects whether metastability could occur when latching any of the plurality of the asynchronous outputs of the asynchronous logic circuit using said clock signal, and activates the stretch signal while the metastability could occur.
Penedo, Janaina Rodrigues; Diniz, Morganna; Ferreira, Simone Bacellar Leal; Silveira, Denis S.; Capra, Eliane
Purpose: The purpose of this paper is to analyze the usability of a remote learning system in its initial development phase, using a quantitative usability evaluation method through Markov models. Design/methodology/approach: The paper opted for an exploratory study. The data of interest of the research correspond to the possible accesses of users…
unless confronted with alternative images. This study delineates six images of usability: universal usability, situational usability, perceived usability, hedonic usability, organizational usability, and cultural usability. The different foci of the images provide opportunities for becoming sensitized...... assume different images of usability and a need for supplementary methods addressing the collaborative and long-term aspects of usability. Moreover, the images call for extending the scope of practical usability work to include the effects achieved by users during their use of systems for real work....
Botvinnik, M M
Asynchronized Synchronous Machines focuses on the theoretical research on asynchronized synchronous (AS) machines, which are "hybrids of synchronous and induction machines that can operate with slip. Topics covered in this book include the initial equations; vector diagram of an AS machine; regulation in cases of deviation from the law of full compensation; parameters of the excitation system; and schematic diagram of an excitation regulator. The possible applications of AS machines and its calculations in certain cases are also discussed. This publication is beneficial for students and indiv
An asynchronous analog to digital convertor for converting an analog input signal into a digital output is presented. According to an embodiment, the analog to digital convertor comprises a clock input operable to receive an external clock signal having a clock period, a comparator operable to
Honda, Kohei; Yoshida, Nobuko; Carbone, Marco
. This work extends the foregoing theories of binary session types to multiparty, asynchronous sessions, which often arise in practical communication-centered applications. Presented as a typed calculus for mobile processes, the theory introduces a new notion of types in which interactions involving multiple......Communication is a central elements in software development. As a potential typed foundation for structured communication-centered programming, session types have been studied over the past decade for a wide range of process calculi and programming languages, focusing on binary (two-party) sessions...... peers are directly abstracted as a global scenario. Global types retain the friendly type syntax of binary session types while specifying dependencies and capturing complex causal chains of multiparty asynchronous interactions. A global type plays the role of a shared agreement among communication peers...
Hertzum, Morten; Clemmensen, Torkil
distinguishing it from user experience. On the basis of repertory-grid interviews with 24 Chinese, Danish, and Indian usability professionals we find that they make use of more utilitarian than experiential, i.e. user-experience related, constructs. This indicates that goal-related performance is central......’ constructs, particularly their experiential constructs, go considerably beyond ISO 9241 usability, indicating a discrepancy between this definition of usability and the thinking of the professionals concerned with delivering usability. Finally, usability is construed rather similarly across the three...
Nielsen, Sune Fallgaard
This thesis presents a method for behavioral synthesis of asynchronous circuits, which aims at providing a synthesis flow which uses and tranfers methods from synchronous circuits to asynchronous circuits. We move the synchronous behavioral synthesis abstraction into the asynchronous handshake...... is idle. This reduces unnecessary switching activity in the individual functional units and therefore the energy consumption of the entire circuit. A collection of behavioral synthesis algorithms have been developed allowing the designer to perform time and power constrained design space exploration...
Usability studies are important for developing usable, enjoyable products, identifying design flaws (usability problems) likely to compromise the user experience. Usability testing is recommended for improving interactive design, but discovery of usability problems depends on the number of users
Damgård, Ivan Bjerre; Geisler, Martin; Krøigaard, Mikkel
guarantees termination if the adversary allows a preprocessing phase to terminate, in which no information is released. The communication complexity of this protocol is the same as that of a passively secure solution up to a constant factor. It is secure against an adaptive and active adversary corrupting...... less than n/3 players. We also present a software framework for implementation of asynchronous protocols called VIFF (Virtual Ideal Functionality Framework), which allows automatic parallelization of primitive operations such as secure multiplications, without having to resort to complicated...... multithreading. Benchmarking of a VIFF implementation of our protocol confirms that it is applicable to practical non-trivial secure computations....
Odor, Alberto; Yellowlees, Peter; Hilty, Donald; Parish, Michelle Burke; Nafiz, Najia; Iosif, Ana-Maria
To describe the technical development of an asynchronous telepsychiatry application, the Psychiatric Video Archiving and Communication System. A client-server application was developed in Visual Basic.Net with Microsoft(®) SQL database as the backend. It includes the capability of storing video-recorded psychiatric interviews and manages the workflow of the system with automated messaging. Psychiatric Video Archiving and Communication System has been used to conduct the first ever series of asynchronous telepsychiatry consultations worldwide. A review of the software application and the process as part of this project has led to a number of improvements that are being implemented in the next version, which is being written in Java. This is the first description of the use of video recorded data in an asynchronous telemedicine application. Primary care providers and consulting psychiatrists have found it easy to work with and a valuable resource to increase the availability of psychiatric consultation in remote rural locations.
Blewett, Richard; Ltd, Rock Solid Knowledge
Pro Asynchronous Programming with .NET teaches the essential skill of asynchronous programming in .NET. It answers critical questions in .NET application development, such as: how do I keep my program responding at all times to keep my users happy how do I make the most of the available hardware how can I improve performanceIn the modern world, users expect more and more from their applications and devices, and multi-core hardware has the potential to provide it. But it takes carefully crafted code to turn that potential into responsive, scalable applications.With Pro Asynchronous Programming
Morgan, Eric Lease
Suggests that one of the best ways to get word-of-mouth marketing of library technology is to provide "usable" products and services. Provides an international standards definition on usability and notes that understanding usability combines an understanding of user needs/wants with an understanding of goals, functions, and limitations…
Usability testing seems complicated and time-consuming. Is it though? In fact, it is the best way to understand how real users experience your product. In this interactive session, we will do a live usability test and you will get advice on how to conduct your own usability tests.
Industrial usability work often fails to produce the expected impact on software products even though significant resources have been used on uncovering problems and suggesting improvements. So, it seems that feedback from industrial usability work lacks persuasiveness, i.e. it fails to convince...... the key stakeholders that actions need to be taken. This study reports from interviews with 26 stakeholders in software development projects. Our data suggests that the interviewees address usability using different perspectives and based on our observations we describe five such perspectives. Further, we...... discuss how applying different usability perspectives might inform the persuasiveness of usability work....
Mohd Dani Baba; A Nasoruddin Mohamad
This paper examines the application of Asynchronous Transfer Mode (ATM) in a distributed industrial environment such as in teleoperation, which performs real time control manipulation from a remote location. In our study, two models of teleoperation are proposed; the first model is a point to point connection and the second model is through an ATM network. The performance results are analysed as to determine whether the two models can support the teleoperation traffics via simulation using commercial software design tool. (Author)
Snider, Jean; Martin, Florence
Web usability focuses on design elements and processes that make web pages easy to use. A website for college students was evaluated for underutilization. One-on-one testing, focus groups, web analytics, peer university review and marketing focus group and demographic data were utilized to conduct usability evaluation. The results indicated that…
Hertzum, Morten; Clemmensen, Torkil; Hornbæk, Kasper
Whereas the concept of usability is predominantly defined analytically, people relate to systems through personal usability constructs. Based on 48 repertory-grid interviews, this study investigates how such personal constructs are affected by two factors crucial to the international development...
Clemmensen, Torkil; Goyal, Shivam
In this paper, we present the results of a pilot study in Denmark of cross cultural effects on Think Aloud usability testing. We provide an overview of previous research on cross cultural usability evaluation with a special focus on the relationship between the evaluator and the test user....... This relation was studied in an experiment with usability testing of a localized clipart application in which eight participants from Denmark and India formed pairs of evaluator-test user. The test users were asked to think aloud and the evaluators' role were to facilitate the test users thinking aloud...... and hereby identify usability problems with the clipart application. Data on the evaluators' and test users' behaviour were recorded and analyzed by coding and summarizing statistics on these behavioural events. The results show that Think Aloud Usability Test of a localized application is most effectively...
-synchronous, mesochronous, globally-asynchronous locally-synchronous and fully asynchronous), discusses the circuitry needed to implement these timing methodologies, and provides some implementation details for a couple of asynchronous NoCs designed at the Technical University of Denmark (DTU). The paper is written...... to support an invited talk at the NORCHIP’2007 conference....
Chandesris, Jérôme; Dennunzio, Alberto; Formenti, Enrico; Manzoni, Luca
This work studies some aspects of the computational power of fully asynchronous cellular automata (ACA). We deal with some notions of simulation between ACA and Turing Machines. In particular, we characterize the updating sequences specifying which are "universal", i.e., allowing a (specific family of) ACA to simulate any TM on any input. We also consider the computational cost of such simulations.
Meinald T. Thielsch
Full Text Available Usability is a core construct of website evaluation and inherently defined as interactive. Yet, when analysing first impressions of websites, expected usability, i.e., before use, is of interest. Here we investigate to what extend ratings of expected usability are related to (a experienced usability, i.e., ratings after use, and (b objective usability measures, i.e., task performance. Furthermore, we try to elucidate how ratings of expected usability are correlated to aesthetic judgments. In an experiment, 57 participants submitted expected usability ratings after the presentation of website screenshots in three viewing-time conditions (50, 500, and 10,000 ms and after an interactive task (experienced usability. Additionally, objective usability measures (task completion and duration and subjective aesthetics evaluations were recorded for each website. The results at both the group and individual level show that expected usability ratings are not significantly related either to experienced usability or objective usability measures. Instead, they are highly correlated with aesthetics ratings. Taken together, our results highlight the need for interaction in empirical website usability testing, even when exploring very early usability impressions. In our study, user ratings of expected usability were no valid proxy neither for objective usability nor for experienced website usability.
Følstad, Asbjørn; Lai-Chong Law, Effie; Hornbæk, Kasper
While the planning and implementation of usability evaluations are well described in the literature, the analysis of the evaluation data is not. We present interviews with 11 usability professionals on how they conduct analysis, describing the resources, collaboration, creation of recommendations......, and prioritization involved. The interviews indicate a lack of structure in the analysis process and suggest activities, such as generating recommendations, that are unsupported by existing methods. We discuss how to better support analysis, and propose four themes for future research on analysis in usability...
Full Text Available Usability, most often defined as the ease of use and acceptability of a system, affects the users' performance and their job satisfaction when working with a machine. Therefore, usability is a very important aspect which must be considered in the process of a system development. The paper presents several numerical data related to the history of the scientific research of the usability of information systems, as it is viewed in the information provided by three important scientific databases, Science Direct, ACM Digital Library and IEEE Xplore Digital Library, at different queries related to this field.
Christensen, Lars; Frøkjær, Erik
We present DUE (Distributed Usability Evaluation), a technique for collecting and evaluating usability data. The DUE infrastructure involves a client-server network. A client-based tool resides on the workstation of each user, providing a screen video recording, microphone input of voice commentary......, and a window for a severity rating. The idea is for the user to work naturalistically, clicking a button when a usability problem or point of uncertainty is encountered, to describe it verbally along with illustrating it on screen, and to rate its severity. These incidents are accumulated on a server......, providing access to an evaluator (usability expert) and to product developers or managers who want to review the incidents and analyse them. DUE supports evaluation in the development stages from running prototypes and onwards. A case study of the use of DUE in a corporate environment is presented...
Rubio, Francisco; Bencomo, Sebastián
This book sheds light on networked control systems; it describes different techniques for asynchronous control, moving away from the periodic actions of classical control, replacing them with state-based decisions and reducing the frequency with which communication between subsystems is required. The text focuses specially on event-based control. Split into two parts, Asynchronous Control for Networked Systems begins by addressing the problems of single-loop networked control systems, laying out various solutions which include two alternative model-based control schemes (anticipatory and predictive) and the use of H2/H∞ robust control to deal with network delays and packet losses. Results on self-triggering and send-on-delta sampling are presented to reduce the need for feedback in the loop. In Part II, the authors present solutions for distributed estimation and control. They deal first with reliable networks and then extend their results to scenarios in which delays and packet losses may occur. The novel ...
For many health programmes, developing interprofessional education (IPE) has been a challenge. Evidence on the best method for design and implementation of IPE has been slow to emerge, with little research on how to best incorporate IPE in the asynchronous online learning environment. This leaves online programmes with no clear guidance when embarking upon an initiative to integrate IPE into the curriculum. One tool that can be effective at guiding the incorporation of IPE across all learning platforms is the Interprofessional Education Collaborative (IPEC) competencies. A project was designed to integrate the nationally defined IPEC competencies throughout an asynchronous, online baccalaureate nursing completion programme. A programme-wide review led to targeted revision of course and unit-level objectives, learning experiences, and assessments based on the IPEC framework. As a result of this effort, the programme curriculum now provides interprofessional learning activities across all courses. This report provides a method for using the IPEC competencies to incorporate IPE within various asynchronous learning assessments, assuring students learn about, with, and from other professions.
Campbell, Bryan A; Tossell, Chad C; Byrne, Michael D; Kortum, Philip
The goal of this research was to assess the usability of a voting system designed for smart-phones. Smartphones offer remote participation in elections through the use of pervasive technology. Voting on these devices could, among other benefits, increase voter participation while allowing voters to use familiar technology. However, the usability of these systems has not been assessed. A mobile voting system optimized for use on a smartphone was designed and tested against traditional voting platforms for usability. There were no reliable differences between the smartphone-based system and other voting methods in efficiency and perceived usability. More important, though, smartphone owners committed fewer errors on the mobile voting system than on the traditional voting systems. Even with the known limitations of small mobile platforms in both displays and controls, a carefully designed system can provide a usable voting method. Much of the concern about mobile voting is in the area of security; therefore, although these results are promising, security concerns and usability issues arising from mitigating them must be strongly considered. The results of this experiment may help to inform current and future election and public policy officials about the benefits of allowing voters to vote with familiar hardware.
Nørgaard, Mie; Hornbæk, Kasper
In theory, usability work is an important and well-integrated activity in developing software. In practice, collaboration on improving usability is ridden with challenges relating to conflicting professional goals, tight project schedules, and unclear usability findings. The authors study those...... challenges through 16 interviews with software developers, usability experts, and project managers. Four themes that are key challenges to successful interaction between stakeholders are identified: poor timing when delivering usability results, results lacking relevance, little respect for other disciplines...
National Aeronautics and Space Administration — Develop, integrate, and deploy software-based tools to coordinate asynchronous, distributed missions and optimize observation planning spanning simultaneous...
Baeten, J.C.M.; Bergstra, J.A.
A version of classical real space process algebra is given in which messages travel with constant speed through a three-dimensional medium. It follows that communication is asynchronous and has a broadcasting character. A state operator is used to describe asynchronous message transfer and a
Bergstra, J.A.; Baeten, J.C.M.
A version of classical real space process algebra is given in which messages travel with constant speed through a three-dimensional medium. It follows that communication is asynchronous and has a broadcasting character. A state operator is used to describe asynchronous message transfer and a
Bergmans, J.W.M.; Pozidis, H.; Lin, M.Y.
Digital data receivers often operate at a fixed sampling rate 1/Ts that is asynchronous to the baud rate 1/T. A digital equalizer that processes the incoming signal will also be asynchronous, and its adaptation is commonly based on extensions of the LMS algorithm. In this paper, we develop and
This PhD thesis is a contribution to an ongoing debate in Denmark about improving the building design processes of complex buildings, especially in relation to the current hospital developments. It provides knowledge about capturing user needs and defines the process model for usability briefing...... and evaluations, can be fed into briefing and design processes. This PhD thesis proposes methods for usability briefing.Usability is a concept similar to functionality, but usability depends on: subjective view of users, context, culture, situation and experience. Understanding usability is achieved by involving...... users. This PhD thesis extends the research in usability of buildings to include all building design phases, therefore not only proposes usability evaluations, but also defines usability briefing. Briefing, also called architectural programming, is usually understood as one of the first phases...
Storm, Jeroen; Kostons, Danny
Storm, J., & Kostons, D. (2009). Usability at the CELSTEC MediaLab. Presentation about the usability testing, usability research and User Centered Design conducted at the CELSTEC MediaLab. July, 7, 2009, Heerlen, The Netherlands: Open University of the Netherlands.
One of the qualities that has received increased attention in recent decades is usability. A software product with poor usability is likely to fail in a highly competitive market; therefore software developing organizations are paying more and more attention to ensuring the usability of their
Bulens, J.D.; Vullings, L.A.E.; Houtkamp, J.M.; Vanmeulebrouk, B.
As INSPIRE progresses to be implemented in the EU, many new discovery portals are built to facilitate finding spatial data. Currently the structure of the discovery portals is determined by the way spatial data experts like to work. However, we argue that the main target group for discovery portals are not spatial data experts but professionals with limited spatial knowledge, and a focus outside the spatial domain. An exploratory usability experiment was carried out in which three discovery p...
Barrera-Valencia, Camilo; Benito-Devia, Alexis Vladimir; Vélez-Álvarez, Consuelo; Figueroa-Barrera, Mario; Franco-Idárraga, Sandra Milena
Telepsychiatry is defined as the use of information and communication technology (ICT) in providing remote psychiatric services. Telepsychiatry is applied using two types of communication: synchronous (real time) and asynchronous (store and forward). To determine the cost-effectiveness of a synchronous and an asynchronous telepsychiatric model in prison inmate patients with symptoms of depression. A cost-effectiveness study was performed on a population consisting of 157 patients from the Establecimiento Penitenciario y Carcelario de Mediana Seguridad de Manizales, Colombia. The sample was determined by applying Zung self-administered surveys for depression (1965) and the Hamilton Depression Rating Scale (HDRS), the latter being the tool used for the comparison. Initial Hamilton score, arrival time, duration of system downtime, and clinical effectiveness variables had normal distributions (P>.05). There were significant differences (P<.001) between care costs for the different models, showing that the mean cost of the asynchronous model is less than synchronous model, and making the asynchronous model more cost-effective. The asynchronous model is the most cost-effective model of telepsychiatry care for patients with depression admitted to a detention centre, according to the results of clinical effectiveness, cost measurement, and patient satisfaction. Copyright © 2016 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.
Duarte L. Oliveira
Full Text Available FPGAs have been mainly used to design synchronous circuits. Asynchronous design on FPGAs is difficult because the resulting circuit may suffer from hazard problems. We propose a method that implements a popular class of asynchronous circuits, known as burst mode, on FPGAs based on look-up table architectures. We present two conditions that, if satisfied, guarantee essential hazard-free implementation on any LUT-based FPGA. By doing that, besides all the intrinsic advantages of asynchronous over synchronous circuits, they also take advantage of the shorter design time and lower cost associated with FPGA designs.
System interrogates and maintains user-definable data files from remote terminals, using English-like, free-form query language easily learned by persons not proficient in computer programming. System operates in asynchronous mode, allowing any number of inquiries within limitation of available core to be active concurrently.
Abdi, Daniel S.; Bitsuamlak, Girma T.
The article of record as published may be found at http://dx.doi.org/10.1155/2015/295393 A Navier-Stokes equations solver is parallelized to run on a cluster of computers using the domain decomposition method. Two approaches of communication and computation are investigated, namely, synchronous and asynchronous methods. Asynchronous communication between subdomains is not commonly used inCFDcodes; however, it has a potential to alleviate scaling bottlenecks incurred due to process...
Bick, Christian; Field, Michael
Building on the first part of this paper, we develop the theory of functional asynchronous networks. We show that a large class of functional asynchronous networks can be (uniquely) represented as feedforward networks connecting events or dynamical modules. For these networks we can give a complete description of the network function in terms of the function of the events comprising the network: the modularization of dynamics theorem. We give examples to illustrate the main results.
Baeten, JCM Jos; Bergstra, JA Jan
A version of classical real space process algebra is given in which messages travel with constant speed through a three-dimensional medium. It follows that communication is asynchronous and has a broadcasting character. A state operator is used to describe asynchronous message transfer and a priority mechanism allows to express the broadcasting mechanism. As an application, a protocol is specified in which the receiver moves with respect to the sender.
The article is aimed to ATM multiplexor computer model utilisation. Based on simulation runs we try to review aspects of use a synchronous and asynchronous ATM multiplexors. ATM multiplexor is the input queuing model with three inputs. Synchronous multiplexor works without an input priority. Multiplexor inputs are served periodically. Asynchronous multiplexor model supports several queuing and priority mechanisms. CLR and CTD are basic performance parameters. Input cell flows are genera...
Aloise, Fabio; Schettini, Francesca; Aricò, Pietro; Salinari, Serenella; Guger, Christoph; Rinsma, Johanna; Aiello, Marco; Mattia, Donatella; Cincotti, Febo
Motor disability and/or ageing can prevent individuals from fully enjoying home facilities, thus worsening their quality of life. Advances in the field of accessible user interfaces for domotic appliances can represent a valuable way to improve the independence of these persons. An asynchronous P300-based Brain-Computer Interface (BCI) system was recently validated with the participation of healthy young volunteers for environmental control. In this study, the asynchronous P300-based BCI for the interaction with a virtual home environment was tested with the participation of potential end-users (clients of a Frisian home care organization) with limited autonomy due to ageing and/or motor disabilities. System testing revealed that the minimum number of stimulation sequences needed to achieve correct classification had a higher intra-subject variability in potential end-users with respect to what was previously observed in young controls. Here we show that the asynchronous modality performed significantly better as compared to the synchronous mode in continuously adapting its speed to the users' state. Furthermore, the asynchronous system modality confirmed its reliability in avoiding misclassifications and false positives, as previously shown in young healthy subjects. The asynchronous modality may contribute to filling the usability gap between BCI systems and traditional input devices, representing an important step towards their use in the activities of daily living.
Moore, Mary; Bias, Randolph G; Prentice, Katherine; Fletcher, Robin; Vaughn, Terry
Skilled website developers value usability testing to assure user needs are met. When the target audience differs substantially from the developers, it becomes essential to tailor both design and evaluation methods. In this study, researchers carried out a multifaceted usability evaluation of a website (Healthy Texas) designed for Hispanic audiences with lower computer literacy and lower health literacy. METHODS INCLUDED: (1) heuristic evaluation by a usability engineer, (2) remote end-user testing using WebEx software; and (3) face-to-face testing in a community center where use of the website was likely. Researchers found standard usability testing methods needed to be modified to provide interpreters, increased flexibility for time on task, presence of a trusted intermediary such as a librarian, and accommodation for family members who accompanied participants. Participants offered recommendations for website redesign, including simplified language, engaging and relevant graphics, culturally relevant examples, and clear navigation. User-centered design is especially important when website developers are not representative of the target audience. Failure to conduct appropriate usability testing with a representative audience can substantially reduce use and value of the website. This thorough course of usability testing identified improvements that benefit all users but become crucial when trying to reach an underserved audience.
Klein Teeselink, G.; Siepe, A.H.M.; Pijper, de J.R.
The aim of this study is to gain insight in the usefulness of log file analysis as a method to evaluate the usability of individual interface components and their influence on the usability of the overall user interface. We selected a music player as application, with four different interfaces and
Folmer, E; van Gurp, J; Bosch, J; Bastide, R; Palanque, P; Roth, J
Studies of software engineering projects show that a large number of usability related change requests are made after its deployment. Fixing usability problems during the later stages of development often proves to be costly, since many of the necessary changes require changes to the system that
The concept of remote maintenance as it pertains to nuclear fuel fabrication facilities is quite unique. The future may require completely remote facilities where maintenance will be performed by hybrid manipulators/robots. These units will be capable of being preprogrammed for automatic operation or manually operated with the operator becoming a part of the closed loop control system. These robots will mesh television, computer control, and direct force feedback manual control in a usable new concept of robotics
Cheng, Yiwei; Richardson, Sally
As part of the Stage Analysis Branch, human factors engineering plays an important role in relating humans to the systems of hardware and structure designs of the new launch vehicle. While many branches are involved in the technical aspects of creating a launch vehicle, human factors connects humans to the scientific systems with the goal of improving operational performance and safety while reducing operational error and damage to the hardware. Human factors engineers use physical and computerized models to visualize possible areas for improvements to ensure human accessibility to components requiring maintenance and that the necessary maintenance activities can be accomplished with minimal risks to human and hardware. Many methods of testing are used to fulfill this goal, such as physical mockups, computerized visualization, and usability testing. In this analysis, a usability test is conducted to test how usable a website is to users who are and are not familiar with it. The testing is performed using participants and Morae software to record and analyze the results. This analysis will be a preliminary test of the usability lab in preparation for use in new spacecraft programs, NASA Enterprise, or other NASA websites. The usability lab project is divided into two parts: integration of the usability lab and a preliminary test of the usability lab.
Huang, Anni; Joo, Sung-Kwan; Song, Kyung-Bin; Kim, Jin-Ho; Lee, Kisung
This paper presents an asynchronous decentralized method to solve the optimization problem of interconnected electricity markets. The proposed method decomposes the optimization problem of combined electricity markets into individual optimization problems. The impact of neighboring markets' information is included in the objective function of the individual market optimization problem by the standard Lagrangian relaxation method. Most decentralized optimization methods use synchronous models of communication to exchange updated market information among markets during the iterative process. In this paper, however, the solutions of the individual optimization problems are coordinated through an asynchronous communication model until they converge to the global optimal solution of combined markets. Numerical examples are presented to demonstrate the advantages of the proposed asynchronous method over the existing synchronous methods. (author)
Mukund, Madhavan; Nielsen, Mogens
We provide a simple non-interleaved operational semantics for CCS in terms of asynchronous transition systems. We identify the concurrency present in the system in a natural way, in terms of events occurring at independent locations in the system. We extend the standard interleaving transition...... system for CCS by introducing labels on the transitions with information about the locations of events. We then show that the resulting transition system is an asynchronous transition system which has the additional property of being elementary, which means that it can also be represented by a 1-safe net....... We also introduce a notion of bisimulation on asynchronous transition systems which preserves independence. We conjecture that the induced equivalence on CCS processes coincides with the notion of location equivalence proposed by Boudol et al....
Burleigh, Scott C.
This software provides a library of middleware functions with a simple application programming interface, enabling implementation of distributed applications in conformance with the CCSDS AMS (Consultative Committee for Space Data Systems Asynchronous Message Service) specification. The AMS service, and its protocols, implement an architectural concept under which the modules of mission systems may be designed as if they were to operate in isolation, each one producing and consuming mission information without explicit awareness of which other modules are currently operating. Communication relationships among such modules are self-configuring; this tends to minimize complexity in the development and operations of modular data systems. A system built on this model is a society of generally autonomous, inter-operating modules that may fluctuate freely over time in response to changing mission objectives, modules functional upgrades, and recovery from individual module failure. The purpose of AMS, then, is to reduce mission cost and risk by providing standard, reusable infrastructure for the exchange of information among data system modules in a manner that is simple to use, highly automated, flexible, robust, scalable, and efficient. The implementation is designed to spawn multiple threads of AMS functionality under the control of an AMS application program. These threads enable all members of an AMS-based, distributed application to discover one another in real time, subscribe to messages on specific topics, and to publish messages on specific topics. The query/reply (client/server) communication model is also supported. Message exchange is optionally subject to encryption (to support confidentiality) and authorization. Fault tolerance measures in the discovery protocol minimize the likelihood of overall application failure due to any single operational error anywhere in the system. The multi-threaded design simplifies processing while enabling application nodes to
Longitudinal studies of the usability of a computer based system for process control has been performed. The whole life-cycle of one system has been of interest, as the problems are varying over time. Repeated measurements of the operators' experiences of this system have been made during 15 years. Of main interest have been the advantages/ disadvantages of computer based system for process control compared with conventional instrumentation. The results showed among other things that (1) computer based systems made it easier to control the process and increased security (2) age differences could be explained by other factors (3 ) expectations before the installation may influence the attitudes and use of equipment for quite some time In some questions the attitudes changed over time while in others they were quite stable, for example, in questions concerning preference for type of equipment. What do operators appreciate in a computer based system for process control? About 300 operators were asked about that. The main factor seems to include a reliable system with valid information that functions during disturbances. Hopefully new systems are designed with that in mind. (author)
Webster, S.A.; Tomasi, L.T.; Bernier, R.A.
After 2 yr of preparation, 1988 finally saw the nuclear industry writing operator-oriented technical specifications. This effort is a continuation of previous efforts to develop improved and usable standard technical specifications (STSs), and is being conducted by the four nuclear steam supply system vendor owners' groups under the auspices of the Nuclear Management Resources Council. Each participant is currently preparing a set of improved STSs based on a writer's guide that was developed through a combined industry effort. In May of 1987, a Human Factors Improvements to Technical Specifications (HFITS) task group was formed to prepare a writer's guide for improved, industrywide STSs. This task group was composed of two representatives from each owners' group, one with a human factors background and one with some operations background. Two documents were prepared in 6 months, a human factors report laying the groundwork for the considerations to go into technical specifications and a writer's guide for their preparation. This paper reports on the application of this writer's guide to the writing of improved STS
Full Text Available Implementation methods for the digital asynchronous systems use different predefined models like self timed circuits, speed independent circuits, delay insensitive circuits, handshake protocol implementation in asynchronous systems,C Muller circuits.
Full Text Available Implementation methods for the digital asynchronous systems use different predefined models like self timed circuits, speed independent circuits, delay insensitive circuits, handshake protocol implementation in asynchronous systems,C Muller circuits.
Proximity measuring device with backscattering radiation usable noticeably in remote handling or robotics and related data processing system. Proximetre a rayonnement retrodiffuse utilisable notamment en telemanipulation ou robotique et systeme de traitement associe
Andre, G; Espiau, B
The invention is aimed at a proximity measuring device whose emitter, an electroluminescent diode, is controlled by control means to emit short duration (< 10 microseconds), high intensity (> 1A) flashes with periods higher than 100 microseconds. Emetter-object distance can be precisely measured on an 0-30 cm interval with the help of data processing of the response given by the proximity device receiver. This device can be used in remote handling and robotics.
Full Text Available This paper presents a modified interpolation algorithm for signals with variable data rate from asynchronous ADCs. The Adaptive weights Conjugate gradient Toeplitz matrix (ACT algorithm is extended to operate with a continuous data stream. An additional preprocessing of data with constant and linear sections and a weighted overlap of step-by-step into spectral domain transformed signals improve the reconstruction of the asycnhronous ADC signal. The interpolation method can be used if asynchronous ADC data is fed into synchronous digital signal processing.
This handbook deals with the asynchronous machine in its close environment. It was born from a reflection on this electromagnetic converter whose integration in industrial environments takes a wide part. Previously this type of motor operated at fixed speed, from now on it has been integrated more and more in processes at variable speed. For this reason it seemed useful, or necessary, to write a handbook on the various aspects from the motor in itself, via the control and while finishing by the diagnosis aspect. Indeed, an asynchronous motor is used nowadays in industry where variation speed a
This book is dedicated to new mathematical instruments assigned for logical modeling of the memory of digital devices. The case in point is logic-dynamical operation named venjunction and venjunctive function as well as sequention and sequentional function. Venjunction and sequention operate within the framework of sequential logic. In a form of the corresponding equations, they organically fit analytical expressions of Boolean algebra. Thus, a sort of symbiosis is formed using elements of asynchronous sequential logic on the one hand and combinational logic on the other hand. So, asynchronous
Do you want to improve the usability of your library website, but feel that it is too difficult, time-consuming, or expensive? Usability Testing: A Practical Guide for Librarians will teach you how to make the case for usability testing, define your audience and their goals, select a usability testing method appropriate for your particular context, plan for an in-house usability test, conduct an effective in-house usability test, analyze usability test results, and create and implement a plan for ongoing, systematic usability testing. Step-by-step instructions, along with a myriad of examples,
Severity assessments enable prioritization of problems encountered during usability evaluations and thereby provide a device for guiding the utilization of design resources. However, designers' response to usability evaluations is also influenced by other factors, which may overshadow severity....... With the purpose of enhancing the impact of severity assessments, this study combines a field study of factors that influence the impact of evaluations with an experimental study of severity assessments made during usability inspections. The results show that even in a project receptive to input from evaluations...... their impact was highly dependent on conducting evaluations early. This accorded with an informal method that blended elements of usability evaluation and participatory design and could be extended with user-made severity assessments. The major cost associated with the evaluations was not finding but fixing...
Vi, Chi Thanh; Hornbæk, Kasper; Subramanian, Sriram
Usability has a distinct subjective component, yet surprisingly little is known about its neural basis and relation to the neuroanatomy of aesthetics. To begin closing this gap, we conducted two functional magnetic resonance imaging studies in which participants were shown static webpages (in...... the first study) and videos of interaction with webpages (in the second study). The webpages were controlled so as to exhibit high and low levels of perceived usability and perceived aesthetics. Our results show unique links between perceived usability and brain areas involved in functions such as emotional...... processing (left fusiform gyrus, superior frontal gyrus), anticipation of physical interaction (precentral gyrus), task intention (anterior cingulate cortex), and linguistic processing (medial and bilateral superior frontal gyri). We use these findings to discuss the brain correlates of perceived usability...
Clemmensen, Torkil; Yammiyavar, Pradeep; Ørngreen, Rikke
This paper focuses on presenting and discussing the aim, context, challenges, results, and impact of the Cultural usability project named as CultUsab. This project was a four year international research effort from 2006 to 2009, which was supported by a grant for the Danish Research Councils...... for Independent Research in Culture and Communication. The project aimed at innovating processes in Information and Communication Technology development through an understanding of culturally sensitive aspects of usability evaluation methods....
Northey, Gavin; Bucic, Tania; Chylinski, Mathew; Govind, Rahul
Student engagement is an ongoing concern for educators because of its positive association with deep learning and educational outcomes. This article tests the use of a social networking site (Facebook) as a tool to facilitate asynchronous learning opportunities that complement face-to-face interactions and thereby enable a stronger learning…
Full Text Available Many constant time algorithms for various problems have been developed for the reconfigurable mesh (RM in the past decade. All these algorithms are designed to work with synchronous execution, with no regard for the fact that large size RMs will probably be asynchronous. A similar observation about the PRAM model motivated many researchers to develop algorithms and complexity measures for the asynchronous PRAM (APRAM. In this work, we show how to define the asynchronous reconfigurable mesh (ARM and how to measure the complexity of asynchronous algorithms executed on it. We show that connecting all processors in a row of an n×n ARM (the analog of barrier synchronization in the APRAM model can be solved with complexity Θ(nlogn. Intuitively, this is average work time for solving such a problem. Next, we describe general a technique for simulating T -step synchronous RM algorithms on the ARM with complexity of Θ(T⋅n2logn. Finally, we consider the simulation of the classical synchronous algorithm for counting the number of non-zero bits in an n bits vector using (k
ICTs and their utilization is one of the most pertinent issues in the education industry today. ... The paper pointed out specific impact of asynchronous ICT media in ... The paper finally noted that the struggle to be part of the digital world is ...
Motycka, Carol A.; St. Onge, Erin L.; Williams, Jennifer
Objective: To better understand the technology being used today in pharmacy education through a review of the current methodologies being employed at various institutions. Also, to discuss the benefits and difficulties of asynchronous and synchronous methodologies, which are being utilized at both traditional and distance education campuses.…
At the core of the suite of adaptive hatching hypotheses advanced to explain asynchronous hatching in birds is the assumption that if food is not limited then all the hatchlings will develop normally to adulthood. In this study Brown-headed Parrot Poicephalus cryptoxanthus chicks were hand fed and weighed on a daily basis.
The per-phase parameters of a 1.5 hp, 380 V, 50 Hz, 4 poles, 3 phase asynchronous machine used in the simulation were computed with reading obtained from a dc, no-load and blocked rotor tests carried out on the machine in the laboratory. The results obtained from the computer simulations confirmed the capabilities ...
Grelck, C.; Scholz, S.-B.; Shafarenko, A.
We present the rationale and design of S-Net, a coordination language for asynchronous stream processing. The language achieves a near-complete separation between the application code, written in any conventional programming language, and the coordination/communication code written in S-Net. Our
Eriksson, Elina; Cajander, Åsa; Gulliksen, Jan
How do you do usability work when no usability expertise is available? What happens in an organization when system developers, with no previous HCI knowledge, after a 3-day course, start applying usability methods, and particularly field studies? In order to answer these questions qualitative data were gathered through participatory observations, a feed back survey, field study documentation and interviews from 47 system developers from a public authority. Our results suggest that field studies enhance the developer’s understanding of the user perspective, and provide a more holistic overview of the use situation, but that some developers were unable to interpret their observations and see solutions to the users’ problems. The field study method was very much appreciated and has now become standard operating procedure within the organization. However, although field studies may be useful, it does not replace the need for usability pro fes sion als, as their knowledge is essential for more complex observations, analysis and for keeping the focus on usability.
Full Text Available Like any other software system quality attribute, usability places requirements on software components. In particular, it has been demonstrated that certain usability features have a direct impact throughout the software process. This paper details an approach that looks at how to deal with certain usability features in the early software development stages. In particular, we consider usability features as functional usability requirements using patterns that have been termed usability patterns to elicit requirements. Additionally, we clearly establish the responsibilities of all the players at the usability requirements elicitation stage.
May 22, 2013 ... MPC offers more than Traditional Crypto! > MPC goes BEYOND traditional Crypto. > Models the distributed computing applications that simultaneously demands usability and privacy of sensitive data ...
The increasing availability of asynchronous parallel processors has provided opportunities for original and useful work in scientific computing. However, the field of parallel computing is still in a highly volatile state, and researchers display a wide range of opinion about many fundamental questions such as models of parallelism, approaches for detecting and analyzing parallelism of algorithms, and tools that allow software developers and users to make effective use of diverse forms of complex hardware. This volume collects the work of researchers specializing in different aspects of parallel computing, who met to discuss the framework and the mechanics of numerical computing. The far-reaching impact of high-performance asynchronous systems is reflected in the wide variety of topics, which include scientific applications (e.g. linear algebra, lattice gauge simulation, ordinary and partial differential equations), models of parallelism, parallel language features, task scheduling, automatic parallelization techniques, tools for algorithm development in parallel environments, and system design issues
Borkar, Vivek S.; Makhijani, Rahul; Sundaresan, Rajesh
We consider two variants of the classical gossip algorithm. The first variant is a version of asynchronous stochastic approximation. We highlight a fundamental difficulty associated with the classical asynchronous gossip scheme, viz., that it may not converge to a desired average, and suggest an alternative scheme based on reinforcement learning that has guaranteed convergence to the desired average. We then discuss a potential application to a wireless network setting with simultaneous link activation constraints. The second variant is a gossip algorithm for distributed computation of the Perron-Frobenius eigenvector of a nonnegative matrix. While the first variant draws upon a reinforcement learning algorithm for an average cost controlled Markov decision problem, the second variant draws upon a reinforcement learning algorithm for risk-sensitive control. We then discuss potential applications of the second variant to ranking schemes, reputation networks, and principal component analysis.
Full Text Available Our concern is the behaviour of the elementary cellular automata with state set 0,1 over the cell set Z/nZ (one-dimensional finite wrap-around case, under all possible update rules (asynchronicity. Over the torus Z/nZ (n<= 11,we will see that the ECA with Wolfram rule 57 maps any v in F_2^n to any w in F_2^n, varying the update rule. We furthermore show that all even (element of the alternating group bijective functions on the set F_2^n = 0,...,2^n-1, can be computed by ECA57, by iterating it a sufficient number of times with varying update rules, at least for n <= 10. We characterize the non-bijective functions computable by asynchronous rules.
My topic of the thesis is usability of PostgreSQL. It presents basic information aboutPostgreSQL, such as its history, function, and comparison with one of the most popular databases - MySQL. PostgreSQL has been tested in different environments and with different programming languages. The research is based on the documents from PostgreSQL official website.The thesis introduces and proves the usability and the compatibility of PostgreSQL. PostgreSQL has been installed on Windows workstation a...
Clemmensen, Torkil; Hertzum, Morten; Hornbæk, Kasper Anders Søren
We discuss the impact of cultural differences on usability evaluations that are based on the thinking-aloud method (TA). The term ‘cultural differences' helps distinguish differences in the perception and thinking of Westerners (people from Western Europe and US citizens with European origins...... and evaluator. In conclusion, we point to the importance of matching the task presentation to users' cultural background, the different effects of thinking aloud on task performance between Easterners and Westerners, the differences in nonverbal behaviour that affect usability problem detection, and, finally...
Clemmensen, Torkil; Hertzum, Morten; Hornbæk, Kasper Anders Søren
We discuss the impact of cultural differences on usability evaluations that are based on the thinking-aloud method (TA). The term ‘cultural differences’ helps distinguish differences in the perception and thinking of Westerners (people from Western Europe and US citizens with European origins...... and evaluator. In conclusion, we point to the importance of matching the task presentation to users’ cultural background, the different effects of thinking aloud on task performance between Easterners and Westerners, the differences in nonverbal behaviour that affect usability problem detection, and, finally...
Nicolajsen, Hanne Westh; Ahola, Titta; Fleury, Alexandre
In this deliverable usability and user experience are defined in relation to MAGNET Beyond technologies, and it is described how the main MAGNET Beyond concepts can be evaluated through the involvement of users. The concepts include the new "Activity based communication approach" for interacting...... with the MAGNET Beyond system, as well as the core concepts: Personal Network, Personal Network-Federation, Service Discovery, User Profile Management, Personal Network Management, Privacy and Security and Context Awareness. The overall plans for the final usability evaluation are documented based on the present...
Lisa C. Yamagata-Lynch
Full Text Available In this article I will share a qualitative self-study about a 15-week blended 100% online graduate level course facilitated through synchronous meetings on Blackboard Collaborate and asynchronous discussions on Blackboard. I taught the course at the University of Tennessee (UT during the spring 2012 semester and the course topic was online learning environments. The primary research question of this study was: How can the designer/instructor optimize learning experiences for students who are studying about online learning environments in a blended online course relying on both synchronous and asynchronous technologies? I relied on student reflections of course activities during the beginning, middle, and the end of the semester as the primary data source to obtain their insights regarding course experiences. Through the experiences involved in designing and teaching the course and engaging in this study I found that there is room in the instructional technology research community to address strategies for facilitating online synchronous learning that complement asynchronous learning. Synchronous online whole class meetings and well-structured small group meetings can help students feel a stronger sense of connection to their peers and instructor and stay engaged with course activities. In order to provide meaningful learning spaces in synchronous learning environments, the instructor/designer needs to balance the tension between embracing the flexibility that the online space affords to users and designing deliberate structures that will help them take advantage of the flexible space.
Chisman, Janet; Walbridge, Sharon; Diller, Karen
Discusses the development and results of usability testing of Washington State University's Web-based OPAC (online public access catalog); examines how easily users could navigate the catalog and whether they understood what they were seeing; and identifies problems and what action if any was taken. (LRW)
Nielsen, Glen; Vedel, Michael; Jensen, Christian D.
. This is done to ensure an appropriate degree of security, but instead, it makes it difficult for users to remember their password, which results in passwords that are either insecure, but easy to remember, or written down on paper. In this paper we address the problem of usability in user authentication...
Downey, Ryan J; Tate, Mark; Kawai, Hiroyuki; Dixon, Warren E
Asynchronous stimulation has been shown to reduce fatigue during electrical stimulation; however, it may also exhibit a force ripple. We quantified the ripple during asynchronous and conventional single-channel transcutaneous stimulation across a range of stimulation frequencies. The ripple was measured during 5 asynchronous stimulation protocols, 2 conventional stimulation protocols, and 3 volitional contractions in 12 healthy individuals. Conventional 40 Hz and asynchronous 16 Hz stimulation were found to induce contractions that were as smooth as volitional contractions. Asynchronous 8, 10, and 12 Hz stimulation induced contractions with significant ripple. Lower stimulation frequencies can reduce fatigue; however, they may also lead to increased ripple. Future efforts should study the relationship between force ripple and the smoothness of the evoked movements in addition to the relationship between stimulation frequency and NMES-induced fatigue to elucidate an optimal stimulation frequency for asynchronous stimulation. © 2014 Wiley Periodicals, Inc.
Full Text Available To protect users from numerous password inference attacks, we invent a novel context aware privacy enhancing keyboard (PEK for Android touch-based devices. Usually PEK would show a QWERTY keyboard when users input text like an email or a message. Nevertheless, whenever users enter a password in the input box on his or her touch-enabled device, a keyboard will be shown to them with the positions of the characters shuffled at random. PEK has been released on the Google Play since 2014. However, the number of installations has not lived up to our expectation. For the purpose of usable security and privacy, we designed a two-stage usability test and performed two rounds of iterative usability testing in 2016 and 2017 summer with continuous improvements of PEK. The observations from the usability testing are educational: (1 convenience plays a critical role when users select an input method; (2 people think those attacks that PEK prevents are remote from them.
de Jong, Catharina Carolina; Ros, Wynand Jg; Schrijvers, Guus
In support of professional practice, asynchronous communication between the patient and the provider is implemented separately or in combination with Internet-based self-management interventions. This interaction occurs primarily through electronic messaging or discussion boards. There is little evidence as to whether it is a useful tool for chronically ill patients to support their self-management and increase the effectiveness of interventions. The aim of our study was to review the use and usability of patient-provider asynchronous communication for chronically ill patients and the effects of such communication on health behavior, health outcomes, and patient satisfaction. A literature search was performed using PubMed and Embase. The quality of the articles was appraised according to the National Institute for Health and Clinical Excellence (NICE) criteria. The use and usability of the asynchronous communication was analyzed by examining the frequency of use and the number of users of the interventions with asynchronous communication, as well as of separate electronic messaging. The effectiveness of asynchronous communication was analyzed by examining effects on health behavior, health outcomes, and patient satisfaction. Patients' knowledge concerning their chronic condition increased and they seemed to appreciate being able to communicate asynchronously with their providers. They not only had specific questions but also wanted to communicate about feeling ill. A decrease in visits to the physician was shown in two studies (P=.07, P=.07). Increases in self-management/self-efficacy for patients with back pain, dyspnea, and heart failure were found. Positive health outcomes were shown in 12 studies, where the clinical outcomes for diabetic patients (HbA1c level) and for asthmatic patients (forced expiratory volume [FEV]) improved. Physical symptoms improved in five studies. Five studies generated a variety of positive psychosocial outcomes. The effect of
This paper is a survey paper presenting what the author sees as two major and promising trends in the current research in CAD-tools and design-methods for asynchronous circuits. One branch of research builds on top of existing asynchronous CAD-tools that perform syntax directed translation, e...... a conventional synchronous circuit as the starting point, and then adds some form of handshake-based flow-control. One approach keeps the global clock and implements discrete-time asynchronous operation. Another approach substitutes the clocked registers by asynchronous handshake-registers, thus creating truly...
Bruun, Anders; Stage, Jan
a high level of usability in order to enable their users to employ the required functionality, especially if the target user group is elderly people. This paper reports from a usability evaluation of a home telemedicine system. Five elderly persons carried out specified tasks with the system, and based...... on that we identified usability problems with the system. The problems are presented, analysed in relation to 12 different usability themes and related to results from other evaluations of similar systems....
Full Text Available This study presents a usability testing as method, which can be used to improve controlling of web map sites. Study refers to the basic principles of this method and describes particular usability tests of mapping sites. In this paper are identified potential usability problems of web sites: Amapy.cz, Google maps and Mapy.cz. The usability testing was focused on problems related with user interfaces, addresses searching and route planning of the map sites.
Full Text Available (with knowledge of usability engineering and system domain knowledge) who inspect the Indira Padayachee, Paula Kotz? and Alta van der Merwe 302 interface and determine its compliance with recognized usability principles (the ?heuristics... presents a summary of the results of the severity rating. Table 2: Severity Rating Scale for Usability Problems (Nielsen 2007b) 0 I don?t agree that this is a usability problem at all 1 Cosmetic problem only: need not be fixed unless there is extra...
Marcilly, Romaric; Peute, Linda W.; Beuscart-Zephir, Marie-Catherine; Jaspers, Monique W.
In a Health Information Technology (HIT) regulatory context in which the usability of this technology is more and more a critical issue, there is an increasing need for evidence based usability practice. However, a clear definition of evidence based usability practice and how to achieve it is still
Jacobsen, Niels Ebbe; Hertzum, Morten; John, Bonnie E.
Usability tests are applied in industry to evaluate systems and in research as a yardstick for other usability evaluation methods. However, one potential threat to the reliability of usability tests has been left unaddressed: the evaluator effect. In this study, four evaluators analyzed four vide...
Three core themes are explored in eight papers: Usability work as a human activity, usability practice and methods, and persuasiveness of evaluation results and feedback. We explore how usability work is much more than methods and work procedures, and argue that maturing our understanding...
Mueller, Sebastian Achim [ETH Zurich (Switzerland); Buss, Jens [TU Dortmund (Germany)
Imaging Atmospheric Cherenkov Telescopes (IACTs) need fast and large imaging optics to map the faint Cherenkov light emitted in cosmic ray air showers onto their image sensors. Segmented reflectors are inexpensive, lightweight and offer good image quality. However, alignment of the mirror facets remains a challenge. A good alignment is crucial in IACT observations to separate gamma rays from hadronic cosmic rays. We present a star tracking alignment method which is not restricted to clear nights. It normalizes the mirror facet reflections to be independent of the reference star or the cloud coverage. It records asynchronously of the telescope drive which makes the method easy to integrate in existing telescopes. It can be combined with remote facet actuation, but it does not need one to work. Furthermore, it can reconstruct all individual mirror facet point spread functions. We present the method and alignment results on the First Geiger-mode Photo Diode Avalanche Cherenkov Telescope (FACT) on the Canary Island of La Palma, Spain.
Whitaker, Sterling R.; Maki, Gary K.
Design methods for asynchronous sequential pass-transistor circuits, which result in circuits that are hazard- and critical-race-free and which have added degrees of freedom for the input signals, are discussed. The design procedures are straightforward and easy to implement. Two single-transition-time state assignment methods are presented, and hardware bounds for each are established. A surprising result is that the hardware realizations for each next state variable and output variable is identical for a given flow table. Thus, a state machine with N states and M outputs can be constructed using a single layout replicated N + M times.
Chow, Edmond [Georgia Inst. of Technology, Atlanta, GA (United States)
Solving sparse problems is at the core of many DOE computational science applications. We focus on the challenge of developing sparse algorithms that can fully exploit the parallelism in extreme-scale computing systems, in particular systems with massive numbers of cores per node. Our approach is to express a sparse matrix factorization as a large number of bilinear constraint equations, and then solving these equations via an asynchronous iterative method. The unknowns in these equations are the matrix entries of the factorization that is desired.
Høegh, Rune Thaarup; Nielsen, Christian Monrad; Pedersen, Michael Bach
of the system. This article presents results from an exploratory study of 2 ways of providing feedback from a usability evaluation: observation of user tests and reading usability reports. A case study and a field experiment were used to explore how observation and usability reports impact developers......' understanding of usability data. The results indicate that observation of user tests facilitated a rich understanding of usability problems and created empathy with the users and their work. The usability report had a strong impact on the developers' understanding of specific usability problems and supported...
Ramli, Rindra M.; Bukhari, Duaa
This usability testing project was conducted to elicit an understanding of our community use of the library website. The researchers wanted to know how our users are interacting with the library website and the ease of obtaining relevant information from the website. The methodology deployed was computer user testing where participants are made to answer several questions and executing the actions on the library website. Their actions are recorded via Techsmith Camtasia software for later analysis by the researchers.
Ramli, Rindra M.
This usability testing project was conducted to elicit an understanding of our community use of the library website. The researchers wanted to know how our users are interacting with the library website and the ease of obtaining relevant information from the website. The methodology deployed was computer user testing where participants are made to answer several questions and executing the actions on the library website. Their actions are recorded via Techsmith Camtasia software for later analysis by the researchers.
Uldall-Espersen, Tobias; Frøkjær, Erik
Usability, Case Study, Software Engineering, Software Quality, Organizational Impact, Usability Requirement Management, CHI 2007 workshop......Usability, Case Study, Software Engineering, Software Quality, Organizational Impact, Usability Requirement Management, CHI 2007 workshop...
In his article “The Usability Construct: A Dead End?”, Tractinsky (in Human-Computer Interaction) contends that for scientific research on usability to progress, the usability construct should be unbundled and replaced by well-defined constructs. This contention is presented as the conclusion...... that follows naturally from taking a scientist’s viewpoint on usability. Similar calls for definitive concepts – constructs in Tractinsky’s terminology – have been made in other scientific fields with concepts as ambiguous as that of usability. But counterarguments have also been presented....
Jaspers, Monique W M
emerged making combined approaches of laboratory, field and remote usability evaluations of new health care applications more feasible.
V. S. Safaryan
Full Text Available The paper considers stationary and transient processes of an asynchronous two-machine system. A mathematical model for investigation of stationary and transient modes, static characteristics and research results of dynamic process pertaining to starting-up the asynchronous two-machine system has been given in paper.
Joiner, Richard; Jones, Sarah; Doherty, John
Asynchronous computer mediated communication (CMC) would seem to be an ideal medium for supporting development in student argumentation. This paper investigates this assumption through two studies. The first study compared asynchronous CMC with face-to-face discussions. The transactional and strategic level of the argumentation (i.e. measures of…
Nielsen, Lars Skovby; Sparsø, Jens
This paper addresses the design of asynchronous circuits for low power through an example: a filter bank for a digital hearing aid. The asynchronous design re-implements an existing synchronous circuit which is used in a commercial product. For comparison, both designs have been fabricated...
Byczkowska-Lipińska, Liliana; Stakhiv, Petro; Hoholyuk, Oksana; Vasylchyshyn, Ivanna
In the paper the problem of effective mathematical macromodels in the form of state variables intended for asynchronous motor transient analysis is considered. Their comparing with traditional mathematical models of asynchronous motors including models built into MATLAB/Simulink software was carried out and analysis of their efficiency was conducted.
Bouhnik, Dan; Giat, Yahel; Sanderovitch, Yafit
Purpose: The purpose of this study is to characterize learning from asynchronous sources among research and development (R&D) personnel. It aims to examine four aspects of asynchronous source learning: employee preferences regarding self-learning; extent of source usage; employee satisfaction with these sources and the effect of the sources on the…
Smith, S. C.; Al-Assadi, W. K.; Di, J.
As demand increases for circuits with higher performance, higher complexity, and decreased feature size, asynchronous (clockless) paradigms will become more widely used in the semiconductor industry, as evidenced by the International Technology Roadmap for Semiconductors' (ITRS) prediction of a likely shift from synchronous to asynchronous design…
Witzke, Edward L.; Robertson, Perry J.; Pierson, Lyndon G.
A localized wireless communication system for communication between a plurality of circuit boards, and between electronic components on the circuit boards. Transceivers are located on each circuit board and electronic component. The transceivers communicate with one another over spread spectrum radio frequencies. An asynchronous transfer mode protocol controls communication flow with asynchronous transfer mode switches located on the circuit boards.
Pavel Grigorievich Kolpakhchyan
Full Text Available The article deals with the problem of the locomotive asynchronous traction motor control with the AC diesel-electric transmission. The limitations of the torque of the traction motor when powered by the inverter are determined. The recommendations to improve the use of asynchronous traction motor of locomotives with the AC diesel-electric transmission are given.
Oztok, Murat; Zingaro, Daniel; Brett, Clare; Hewitt, Jim
While the independent contributions of synchronous and asynchronous interaction in online learning are clear, comparatively less is known about the pedagogical consequences of using both modes in the same environment. In this study, we examine relationships between students' use of asynchronous discussion forums and synchronous private messages…
Johnson, Genevieve Marie; Buck, George H.
Students in an introductory educational psychology course used two WebCT communication tools (synchronous chat and asynchronous discussion) to discuss four case studies. In response to the item, "I learned the case studies best when using," 39 students selected synchronous chat and 51 students selected asynchronous discussion. Students who…
Høegh, Rune Thaarup
This paper presents a study of the strengths and weaknesses of written, multimedia and oral feedback from usability evaluations to developers. The strengths and weaknesses are related to how well the feedback supports the developers in addressing usability problems in a software system. The study...... concludes that using the traditional written usability report, as the only form of feedback from usability evaluations is associated with problems related to the report not supporting the process of addressing the usability problems. The report is criticized for representing an overwhelming amount...... of information, while still not offering the required information to address usability problems. Other forms of feedback, such as oral or multimedia feedback helps the developer in understanding the usability problems better, but are on the other hand less cost-effective than a written description....
Usability evaluation provide software development teams with insights on the degree to which a software application enables a user to achieve his/her goals, how fast these goals can be achieved, how easy it is to learn and how satisfactory it is in use Although usability evaluations are crucial...... in the process of developing software systems with a high level of usability, its use is still limited in the context of small software development companies. Several approaches have been proposed to support software development practitioners (SWPs) in conducting usability evaluations, and my thesis explores two...... of these: 1) The first approach is to support SWPs by training them to drive usability evaluations. 2) The second approach to support SWPs involves minimalist training of end users to drive usability evaluations. In related work, a set of five quality criteria for usability evaluations is applied...
Cao, Hongyuan; Zeng, Donglin; Fine, Jason P
We consider estimation of regression models for sparse asynchronous longitudinal observations, where time-dependent responses and covariates are observed intermittently within subjects. Unlike with synchronous data, where the response and covariates are observed at the same time point, with asynchronous data, the observation times are mismatched. Simple kernel-weighted estimating equations are proposed for generalized linear models with either time invariant or time-dependent coefficients under smoothness assumptions for the covariate processes which are similar to those for synchronous data. For models with either time invariant or time-dependent coefficients, the estimators are consistent and asymptotically normal but converge at slower rates than those achieved with synchronous data. Simulation studies evidence that the methods perform well with realistic sample sizes and may be superior to a naive application of methods for synchronous data based on an ad hoc last value carried forward approach. The practical utility of the methods is illustrated on data from a study on human immunodeficiency virus.
Konduri, Aditya; Donzis, Diego
Recent advances in computing hardware and software have made simulations an indispensable research tool in understanding fluid flow phenomena in complex conditions at great detail. Due to the nonlinear nature of the governing NS equations, simulations of high Re turbulent flows are computationally very expensive and demand for extreme levels of parallelism. Current large simulations are being done on hundreds of thousands of processing elements (PEs). Benchmarks from these simulations show that communication between PEs take a substantial amount of time, overwhelming the compute time, resulting in substantial waste in compute cycles as PEs remain idle. We investigate a novel approach based on widely used finite-difference schemes in which computations are carried out asynchronously, i.e. synchronization of data among PEs is not enforced and computations proceed regardless of the status of messages. This drastically reduces PE idle time and results in much larger computation rates. We show that while these schemes remain stable, their accuracy is significantly affected. We present new schemes that maintain accuracy under asynchronous conditions and provide a viable path towards exascale computing. Performance of these schemes will be shown for simple models like Burgers' equation.
Adambounou, K; Farin, F; Boucher, A; Adjenou, K V; Gbeassor, M; N'dakena, K; Vincent, N; Arbeille, P
Ultrasonography is an important nonirradiating diagnostic medical imaging procedure, frequently used, especially in urgent circumstances. This relatively inexpensive noninvasive examination makes it possible to diagnose disorders in various parts of the human body, by examining, for example, the abdomen and pelvis, the cardiovascular system, and the muscles and joints. Ultrasound is also an operator-dependent examination, in that the quality of the result depends on precision in the manipulation of the probe. Unfortunately, many small medical centers and isolated sites do not have an appropriate well-trained sonographer to perform initial evaluations, and an untrained operator cannot capture the appropriate echographic views required for a safe diagnosis of current patients, even with realtime vocal guidance (personal data). The lack of experienced physicians or qualified technicians means that diagnostic ultrasound is not always accessible to patients for rapid examination worldwide, especially in Africa, Amazonia or near the North or South Poles. This situation has led to the development of a new concept of telemedicine: telesonography, with a remote ultrasound diagnosis either in real time (synchronous) or delayed (asynchronous; store-and-forward). These systems of real-time telesonography and data transmission require expensive and complex technology with sophisticated equipment not available in many developing countries. The purpose of this study is to design a low-cost real-time system of telesonography for teleconsultations with experts and a delayed telediagnostic mode between isolated peripheral hospitals and a University Hospital center (UHC). An IP camera and an internet video server were installed in a geographically isolated site equipped with an ultrasound machine and an operator with basic training in its use. Synchronous teleconsultation (second-opinion diagnosis) is possible via internet with a UHC expert. If no ultrasound operator is available at
Johansen, Sune Alstrup; San Agustin, Javier; Jensen, Henrik Tomra Skovsgaard Hegner
Accuracy of an open source remote eye tracking system and a state-of-the-art commercial eye tracker was measured 4 times during a usability test. Results from 9 participants showed both devices to be fairly stable over time, but the commercial tracker was more accurate with a mean error of 31 pix...
Bossaller, Jenny S.; Paul, Anindita; Hill, Heather; Wang, Jiazhen; Erdelez, Sanda
This article describes an "on-the-road" usability study and explains the study's methodological challenges, solutions, and recommendations. The study concerned a library-consortium website, which is a communication and educational tool for librarians who are physically dispersed throughout the state, and an intranet for remote users.…
Amitai, Dganit; Averbuch, Amir; Itzikowitz, Samuel; Turkel, Eli
A major problem in achieving significant speed-up on parallel machines is the overhead involved with synchronizing the concurrent process. Removing the synchronization constraint has the potential of speeding up the computation. The authors present asynchronous (AS) and corrected-asynchronous (CA) finite difference schemes for the multi-dimensional heat equation. Although the discussion concentrates on the Euler scheme for the solution of the heat equation, it has the potential for being extended to other schemes and other parabolic partial differential equations (PDEs). These schemes are analyzed and implemented on the shared memory multi-user Sequent Balance machine. Numerical results for one and two dimensional problems are presented. It is shown experimentally that the synchronization penalty can be about 50 percent of run time: in most cases, the asynchronous scheme runs twice as fast as the parallel synchronous scheme. In general, the efficiency of the parallel schemes increases with processor load, with the time level, and with the problem dimension. The efficiency of the AS may reach 90 percent and over, but it provides accurate results only for steady-state values. The CA, on the other hand, is less efficient, but provides more accurate results for intermediate (non steady-state) values.
Fornel, B. de [Institut National Polytechnique, 31 - Toulouse (France)
The asynchronous machine, with its low cost and robustness, is today the most widely used motor to make speed variators. However, its main drawback is that the same current generates both the magnetic flux and the torque, and thus any torque variation creates a flux variation. Such a coupling gives to the asynchronous machine a nonlinear behaviour which makes its control much more complex. The direct self control (DSC) method has been developed to improve the low efficiency of the scalar control method and for the specific railway drive application. The direct torque control (DTC) method is derived from the DSC method but corresponds to other type of applications. The DSC and DTC algorithms for asynchronous motors are presented in this article: 1 - direct control of the stator flux (DSC): principle, flux control, torque control, switching frequency of the inverter, speed estimation; 2 - direct torque control (DTC): principle, electromagnetic torque derivative, signals shape and switching frequency, some results, DTC speed variator without speed sensor, DTC application to multi-machine multi-converter systems; 3 - conclusion. (J.S.)
Stone, D.; Geiger, S.; Lord, G. J.
A new class of asynchronous discrete-event simulation schemes for advection-diffusion-reaction equations is introduced, based on the principle of allowing quanta of mass to pass through faces of a (regular, structured) Cartesian finite volume grid. The timescales of these events are linked to the flux on the face. The resulting schemes are self-adaptive, and local in both time and space. Experiments are performed on realistic physical systems related to porous media flow applications, including a large 3D advection diffusion equation and advection diffusion reaction systems. The results are compared to highly accurate reference solutions where the temporal evolution is computed with exponential integrator schemes using the same finite volume discretisation. This allows a reliable estimation of the solution error. Our results indicate a first order convergence of the error as a control parameter is decreased, and we outline a framework for analysis.
Sallai, Gabriella; Mittal, Ankita; Girimaji, Sharath
Numerical techniques for asynchronous fluid flow simulations are currently under development to enable efficient utilization of massively parallel computers. These numerical approaches attempt to accurately solve time evolution of transport equations using spatial information at different time levels. The truncation error of asynchronous methods can be divided into two parts: delay dependent (EA) or asynchronous error and delay independent (ES) or synchronous error. The focus of this study is a specific asynchronous error mitigation technique called proxy-equation approach. The aim of this study is to examine these errors as a function of the characteristic wavelength of the solution. Mitigation of asynchronous effects requires that the asynchronous error be smaller than synchronous truncation error. For a simple convection-diffusion equation, proxy-equation error analysis identifies critical initial wave-number, λc. At smaller wave numbers, synchronous error are larger than asynchronous errors. We examine various approaches to increase the value of λc in order to improve the range of applicability of proxy-equation approach.
Sørensen, Jannick Kirk
Good usability is important in all ICT solutions. To achieve good usability, a good praxis for interaction design is needed. Usability and interaction design have however emerged and established itself in a North European and US context. The ICT industry in Africa do not have the same resources...... for user-involvement and participatory design be directly transferred? How can interaction design and usability be cared for in African ICT development context, given the resources available? This paper aims to initiate a discussion of the conditions for interaction design and usability in West Africa...... in the field of interaction design as in the developed world. While good usability and good user experiences are important to all users of ICT, the question is whether the methods and techniques that were mainly developed in Scandinavia, Europe and US are suitable for ICT development in Africa? Can ideals...
Ronald L. Boring; David I. Gertman
This paper introduces a novel augmentation to the current heuristic usability evaluation methodology. The SPAR-H human reliability analysis method was developed for categorizing human performance in nuclear power plants. Despite the specialized use of SPAR-H for safety critical scenarios, the method also holds promise for use in commercial off-the-shelf software usability evaluations. The SPAR-H method shares task analysis underpinnings with human-computer interaction, and it can be easily adapted to incorporate usability heuristics as performance shaping factors. By assigning probabilistic modifiers to heuristics, it is possible to arrive at the usability error probability (UEP). This UEP is not a literal probability of error but nonetheless provides a quantitative basis to heuristic evaluation. When combined with a consequence matrix for usability errors, this method affords ready prioritization of usability issues
Følstad, Asbjørn; Hornbæk, Kasper
Usability evaluation helps to determine whether interactive systems support users in their work tasks. However, knowledge about those tasks and, more generally, about the work-domain is difficult to bring to bear on the processes and outcome of usability evaluation. One way to include such work......-domain knowledge might be Cooperative Usability Testing, an evaluation method that consists of (a) interaction phases, similar to classic usability testing, and (b) interpretation phases, where the test participant and the moderator discuss incidents and experiences from the interaction phases. We have studied...... whether such interpretation phases improve the relevance of usability evaluations in the development of work-domain specific systems. The study included two development cases. We conclude that the interpretation phases generate additional insight and redesign suggestions related to observed usability...
Lozano, María D; Tesoriero, Ricardo; Penichet, Victor MR
Written by international researchers in the field of Distributed User Interfaces (DUIs), this book brings together important contributions regarding collaboration and usability in Distributed User Interface settings. Throughout the thirteen chapters authors address key questions concerning how collaboration can be improved by using DUIs, including: in which situations a DUI is suitable to ease the collaboration among users; how usability standards can be used to evaluate the usability of systems based on DUIs; and accurately describe case studies and prototypes implementing these concerns
Vinoth Kumar, K.; Sony, Kevin; Achenkunju John, Alan; Kuriakose, Anto; John, Ano P.
This paper investigates the stator short winding failure of asynchronous motor also their effects on motor current spectrums. A fuzzy logic approach i.e., model based technique possibly will help to detect the asynchronous motor failure. Actually, fuzzy logic similar to humanoid intelligent methods besides expected linguistic empowering inferences through vague statistics. The dynamic model is technologically advanced for asynchronous motor by means of fuzzy logic classifier towards investigate the stator inter turn failure in addition open phase failure. A hardware implementation was carried out with LabVIEW for the online-monitoring of faults.
There has been roughly 15 years of research into approaches for aligning research in Human Computer Interaction with computer Security, more colloquially known as ``usable security.'' Although usability and security were once thought to be inherently antagonistic, today there is wide consensus that systems that are not usable will inevitably suffer security failures when they are deployed into the real world. Only by simultaneously addressing both usability and security concerns will we be able to build systems that are truly secure. This book presents the historical context of the work to dat
future versions of the prod- uct? The results show that users write about product use in terms related to standard and popularly researched aspects of usability and user experience, e.g. effiiency, effectiveness, enjoyment, frustration. The frequency with which different aspects are depicted in reviews...... differs significantly between product domains. We also find that reviews contain descriptions of more persistent usability issues. I devise automatic methods for classifying sentences with regard to dimensions of both usability and user experience and usability problems and perform a linguistic analysis...
Gupta, Deepak; Ahlawat, Anil K.; Sagar, Kalpna
Evaluation of software quality is an important aspect for controlling and managing the software. By such evaluation, improvements in software process can be made. The software quality is significantly dependent on software usability. Many researchers have proposed numbers of usability models. Each model considers a set of usability factors but do not cover all the usability aspects. Practical implementation of these models is still missing, as there is a lack of precise definition of usability. Also, it is very difficult to integrate these models into current software engineering practices. In order to overcome these challenges, this paper aims to define the term `usability' using the proposed hierarchical usability model with its detailed taxonomy. The taxonomy considers generic evaluation criteria for identifying the quality components, which brings together factors, attributes and characteristics defined in various HCI and software models. For the first time, the usability model is also implemented to predict more accurate usability values. The proposed system is named as fuzzy hierarchical usability model that can be easily integrated into the current software engineering practices. In order to validate the work, a dataset of six software development life cycle models is created and employed. These models are ranked according to their predicted usability values. This research also focuses on the detailed comparison of proposed model with the existing usability models.
de Castro Lozano, Carlos; Salcines, Enrique García; Sainz de Abajo, Beatriz; Burón Fernández, F. Javier; Ramírez, José Miguel; Recellado, José Gabriel Zato; Montoya, Rafael Sanchez; Bell, John; Marin, Francisco Alcantud
When designing "interfaces for everyone" for interactive systems, it is important to consider factors such as cost, the intended market, the state of the environment, etc. User interfaces are fundamental for the developmental process in any application, and its design must be contemplated from the start. Of the distinct parts of a system (hardware and software), it is the interface that permits the user access to computer resources. The seven principles of "Universal Design" or "Design for Everyone" focus on a universal usable design, but at the same time acknowledge the influences of internal and external factors. Structural changes in social and health services could provide an increase in the well-being of a country's citizens through the use of self-care programming and proactive management/prevention of disease. Automated home platforms can act as an accessibility instrument which permits users to avoid, compensate, mitigate, or neutralize the deficiencies and dependencies caused by living alone.
Younes, Hakan L
.... The most common assumption is that of history-independence: the Markov assumption. In this thesis, the author considers the problems of verification and planning for stochastic processes with asynchronous events, without relying on the Markov assumption...
Bracco, Chiara; Quaranta, Elena; CERN. Geneva. ATS Department
The protection provided by the TCDQs in case of asynchronous beam dump depends strongly on their correct setup. They have to respect the strict hierarchy of the full collimation system and shield the tertiary collimators in the experimental regions. This MD aimed at performing asynchronous beam dump tests with different configurations, in order to assess the minimum allowed retraction between TCTs and TCDQs and, as a consequence, on the The protection provided by the TCDQs in case of asynchronous beam dump depends strongly on their correct setup. They have to respect the strict hierarchy of the full collimation system and shield the tertiary collimators in the experimental regions. This MD aimed at performing asynchronous beam dump tests with different configurations, in order to assess the minimum allowed retraction between TCTs and TCDQs and, as a consequence, on the β* reach.
The aim of this paper is to report on an experience of using an innovative on-line learning tool to support real, collaborative learning through discussion in asynchronous time. While asynchronous interaction gives rise to unique opportunities that support active, collaborative learning, unique problems also arise, such as frustration, caused by waiting for other peoples' reactions and feedback and the consequent loss of motivation, which has a negative impact on learning outcomes. In order t...
Anzt, H.; Dongarra, J.; Heuveline, Vincent; Tomov, S.
In this paper, we analyze the potential of asynchronous relaxation methods on Graphics Processing Units (GPUs). For this purpose, we developed a set of asynchronous iteration algorithms in CUDA and compared them with a parallel implementation of synchronous relaxation methods on CPU-based systems. For a set of test matrices taken from the University of Florida Matrix Collection we monitor the convergence behavior, the average iteration time and the total time-to-solution time. Analyzing the r...
Full Text Available In this note we describe the theory of functional asynchronous networks and one of the main results, the Modularization of Dynamics Theorem, which for a large class of functional asynchronous networks gives a factorization of dynamics in terms of constituent subnetworks. For these networks we can give a complete description of the network function in terms of the function of the events comprising the network and thereby answer a question originally raised by Alon in the context of biological networks.
Zhuang Shengxian; Peng Anjin; Lars Wanhammar
An asynchronous wrapper with novel handshake circuits for data communication in globally asynchronous locally synchronous (GALS) systems is proposed. The handshake circuits include two communication ports and a local clock generator. Two approaches for the implementation of communication ports are presented, one with pure standard cells and the others with Müller-C elements. The detailed design methodology for GALS systems is given and the circuits are validated with VHDL and circuits simulation in standard CMOS technology.
Jorritsma, Wiard; Cnossen, Fokie; van Ooijen, Peter M. A.
Objectives: To compare the usability of different Picture Archiving and Communication System (PACS) workstations, determine whether a usability test has added value with respect to the traditional way of comparing PACSs based on functional requirements, and to evaluate the appropriateness of a
Ruyter, de B.E.R.; Vet, de J.H.M.
Improving usability of consumer applications has been the focus of much research. Estimating the advantage of these efforts, however, still is very cumbersome since evaluating product improvements in terms of their usability requires good measuring methods and tools. In this paper activities in the
Slama-Belkhodja, I.; de Fornel, B.
The paper deals with an indirect self-tuning speed control for an induction motor supplied by a chopper-filter-inverter system. Input/Output models are identified with the recursive least squares algorithm and the controller adaptation is based on a pole assignement strategy. Emphasis is put on the evaluation of the parameter identification in order to avoid instabilities because of disturbances or insufficient excitations. This is especially of importance when the adaptive control is carried out in closed loop systems and without additional test signals. Simulation results show the improvement of the dynamic responses and the robustness against load variations or parameters variations (rotor resistance, inertia). Cat article décrit une stratégie de commande adaptive indirecte à Placement de Pôles (PP), appliquée à la commande en vitesse d'une machine asynchrone alimentée par un ensemble hacheur-filtre-onduleur de tension. L'algorithme des Moindres Carrés Récursifs (MCR) est utilisé pour l'identification des modèles de comportement type entrées/sorties. Un intérêt particulier est porté à la mise en oeuvre de cet algorithme et à la discussion de ses résultats, tenant compte des erreurs de modélisation et de la nature peu riche en excitations des entrées du processus. Différents régimes transitoires ont été simulés pour apprécier l'apport de cette association (MCR-PP) : démarrages et inversion des sens de rotation, à vide et en charges, applications d'échelons de couple résistant, variations paramétriques. Les résultats permettent d'illustrer, tant au niveau des performances que de la robustesse, l'apport d'une telle commande adaptive pour des entraînements électriques avec une machine asynchrone.
Nørgaard, Mie; Hornbæk, Kasper Anders Søren
The format used to present feedback from usability evaluations to developers affects whether problems are understood, accepted, and fixed. Yet, little research has investigated which formats are the most effective. We describe an explorative study where three developers assess 40 usability findings...... presented using five feedback formats. Our usability findings comprise 35 problems and 5 positive comments. Data suggest that feedback serves multiple purposes. Initially, feedback must convince developers about the relevance of a problem and convey an understanding of this. Feedback must next be easy...... working with the feedback to address the usability problems, there were no significant differences among the developers' ratings of the value of the different formats. This suggests that all of the formats may serve equally well as reminders in later stages of working with usability problems...
Full Text Available Usability is an attribute of any good product, just as its functionality. It refers mainly to the utility of a product for its indented users, as well as to its ease of use. And whilst a correct functionality is critical for the commercial success of any product, its value comes through the human needs that it fulfills, which is determined through various marketing research techniques. In parallel, the IT&C community has developed in the last two decades its own type of research, called usability testing, used mainly to evaluate interface ease of use and all usability problems associated with.software products. This article aims at finding the right place for usability testing and usability professionals in the marketing community, as well as drawing a wider picture, from a marketing research perspective, on one of the most popular topics in IT&C community for the benefit of marketing scholars and professionals.
Uldall-Espersen, Tobias; Frøkjær, Erik; Hornbæk, Kasper Anders Søren
Analyzing usability improvement processes as they take place in real-life organizations is necessary to understand the practice of usability work. This paper describes a case study where the usability of an information system is improved and a relationship between the improvements...... and the evaluation efforts is established. Results show that evaluation techniques complemented each other by suggesting different kinds of usability improvement. Among the techniques applied, a combination of questionnaires and Metaphors of Human Thinking (MOT) showed the largest mean impact and MOT produced...... the largest number of impacts. Logging of real-life use of the system over 6 months indicated six aspects of improved usability, where significant differences among evaluation techniques were found. Concerning five of the six aspects Think Aloud evaluations and the above-mentioned combination of questionnaire...
Lizano, Fulvio; Sandoval, Maria Marta; Bruun, Anders
Several emerging countries experience increasing software development activities. With the purpose of provide useful feedback on possible courses of action for increasing application of usability evaluation in such countries, this paper explores the status of usability evaluation in a digitally...... emerging country. Our aim is to identifying common characteristics or behavioral patterns that could be compared with digitally advanced countries. We used an online survey answered by 26 software development organizations, which gave a snapshot of the application of usability evaluation...... in these organizations. We found many similarities with advanced countries, several completely new obstacles more connected with software development matters and a relatively positive improvement in the lack of “usability culture”. These findings suggest good conditions to improve conduction of usability evaluations...
Full Text Available This paper is focused on the testing and evaluating of public administration electronic forms from the usability point of view. Its objective is to design a suitable methodology for usability testing of electronic forms and their description and distribution to public administration information systems professionals. Firstly, methods of usability engineering are summarized and a suitable method for usability testing and evaluation of electronic forms is selected. Farther, the methodology of electronic forms usability testing that uses the selected method is suggested. In the last part of the paper the case study that uses the proposed methodology is suggested and performed. The main benefit of the work is the design of testing methodology and proposition of the set of recommendations for new public administration electronic forms design.
Full Text Available The brain exhibits temporally complex patterns of activity with features similar to those of chaotic systems. Theoretical studies over the last twenty years have described various computational advantages for such regimes in neuronal systems. Nevertheless, it still remains unclear whether chaos requires specific cellular properties or network architectures, or whether it is a generic property of neuronal circuits. We investigate the dynamics of networks of excitatory-inhibitory (EI spiking neurons with random sparse connectivity operating in the regime of balance of excitation and inhibition. Combining Dynamical Mean-Field Theory with numerical simulations, we show that chaotic, asynchronous firing rate fluctuations emerge generically for sufficiently strong synapses. Two different mechanisms can lead to these chaotic fluctuations. One mechanism relies on slow I-I inhibition which gives rise to slow subthreshold voltage and rate fluctuations. The decorrelation time of these fluctuations is proportional to the time constant of the inhibition. The second mechanism relies on the recurrent E-I-E feedback loop. It requires slow excitation but the inhibition can be fast. In the corresponding dynamical regime all neurons exhibit rate fluctuations on the time scale of the excitation. Another feature of this regime is that the population-averaged firing rate is substantially smaller in the excitatory population than in the inhibitory population. This is not necessarily the case in the I-I mechanism. Finally, we discuss the neurophysiological and computational significance of our results.
Baines, John; The ATLAS collaboration
In order to be able to make effective use of emerging hardware, where the amount of memory available to any CPU is rapidly decreasing as the core count continues to rise, ATLAS has begun a migration to a concurrent, multi-threaded software framework, known as AthenaMT. Significant progress has been made in implementing AthenaMT - we can currently run realistic Geant4 simulations on massively concurrent machines. the migration of realistic prototypes of reconstruction workflows is more difficult, given the large amounts of legacy code and the complexity and challenges of reconstruction software. These types of workflows, however, are the types that will most benefit from the memory reduction features of a multi-threaded framework. One of the challenges that we will report on in this paper is the re-design and implementation of several key asynchronous technologies whose behaviour is radically different in a concurrent environment than in a serial one, namely the management of Conditions data and the Detector D...
Van der Burg, Erik; Goodbourn, Patrick T
The brain is adaptive. The speed of propagation through air, and of low-level sensory processing, differs markedly between auditory and visual stimuli; yet the brain can adapt to compensate for the resulting cross-modal delays. Studies investigating temporal recalibration to audiovisual speech have used prolonged adaptation procedures, suggesting that adaptation is sluggish. Here, we show that adaptation to asynchronous audiovisual speech occurs rapidly. Participants viewed a brief clip of an actor pronouncing a single syllable. The voice was either advanced or delayed relative to the corresponding lip movements, and participants were asked to make a synchrony judgement. Although we did not use an explicit adaptation procedure, we demonstrate rapid recalibration based on a single audiovisual event. We find that the point of subjective simultaneity on each trial is highly contingent upon the modality order of the preceding trial. We find compelling evidence that rapid recalibration generalizes across different stimuli, and different actors. Finally, we demonstrate that rapid recalibration occurs even when auditory and visual events clearly belong to different actors. These results suggest that rapid temporal recalibration to audiovisual speech is primarily mediated by basic temporal factors, rather than higher-order factors such as perceived simultaneity and source identity. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
Coon, D. D.; Perera, A. G. U.
A new hardware approach to implementation of image processing algorithms is described. The approach is based on silicon devices which would permit an independent analog processing channel to be dedicated to evey pixel. A laminar architecture consisting of a stack of planar arrays of the device would form a two-dimensional array processor with a 2-D array of inputs located directly behind a focal plane detector array. A 2-D image data stream would propagate in neuronlike asynchronous pulse coded form through the laminar processor. Such systems would integrate image acquisition and image processing. Acquisition and processing would be performed concurrently as in natural vision systems. The research is aimed at implementation of algorithms, such as the intensity dependent summation algorithm and pyramid processing structures, which are motivated by the operation of natural vision systems. Implementation of natural vision algorithms would benefit from the use of neuronlike information coding and the laminar, 2-D parallel, vision system type architecture. Besides providing a neural network framework for implementation of natural vision algorithms, a 2-D parallel approach could eliminate the serial bottleneck of conventional processing systems. Conversion to serial format would occur only after raw intensity data has been substantially processed. An interesting challenge arises from the fact that the mathematical formulation of natural vision algorithms does not specify the means of implementation, so that hardware implementation poses intriguing questions involving vision science.
Harish, Omri; Hansel, David
The brain exhibits temporally complex patterns of activity with features similar to those of chaotic systems. Theoretical studies over the last twenty years have described various computational advantages for such regimes in neuronal systems. Nevertheless, it still remains unclear whether chaos requires specific cellular properties or network architectures, or whether it is a generic property of neuronal circuits. We investigate the dynamics of networks of excitatory-inhibitory (EI) spiking neurons with random sparse connectivity operating in the regime of balance of excitation and inhibition. Combining Dynamical Mean-Field Theory with numerical simulations, we show that chaotic, asynchronous firing rate fluctuations emerge generically for sufficiently strong synapses. Two different mechanisms can lead to these chaotic fluctuations. One mechanism relies on slow I-I inhibition which gives rise to slow subthreshold voltage and rate fluctuations. The decorrelation time of these fluctuations is proportional to the time constant of the inhibition. The second mechanism relies on the recurrent E-I-E feedback loop. It requires slow excitation but the inhibition can be fast. In the corresponding dynamical regime all neurons exhibit rate fluctuations on the time scale of the excitation. Another feature of this regime is that the population-averaged firing rate is substantially smaller in the excitatory population than in the inhibitory population. This is not necessarily the case in the I-I mechanism. Finally, we discuss the neurophysiological and computational significance of our results. PMID:26230679
Nacke, Lennart E.
This paper presents a brief review of current game usability models. This leads to the conception of a high-level game development-centered usability model that integrates current usability approaches in game industry and game research.
Argues that usability research has particular relevance for enhancing the effectiveness of websites. Examines the nature and value of usability research, and the elements of an effective website based on usability principles. (SR)
Bentley, Richard S
.... The Technology Acceptance Model suggests that information systems must not only be useful but also be usable and a large body of usability engineering knowledge exists to support usable design. In addition, the U.S...
Jones, Matthew O; Kimball, John S; Nemani, Ramakrishna R
Amazon forests represent nearly half of all tropical vegetation biomass and, through photosynthesis and respiration, annually process more than twice the amount of estimated carbon (CO 2 ) from fossil fuel emissions. Yet the seasonality of Amazon canopy cover, and the extent to which seasonal fluctuations in water availability and photosynthetically available radiation influence these processes, is still poorly understood. Implementing six remotely sensed data sets spanning nine years (2003–2011), with reported field and flux tower data, we show that southern equatorial Amazon forests exhibit a distinctive seasonal signal. Seasonal timing of water availability, canopy biomass growth and net leaf flush are asynchronous in regions with short dry seasons and become more synchronous across a west-to-east longitudinal moisture gradient of increasing dry season. Forest cover is responsive to seasonal disparities in both water and solar radiation availability, temporally adjusting net leaf flush to maximize use of these generally abundant resources, while reducing drought susceptibility. An accurate characterization of this asynchronous behavior allows for improved understanding of canopy phenology across contiguous tropical forests and their sensitivity to climate variability and drought. (letter)
Jones, M. O.; Kimball, J. S.; Nemani, R. R.
Amazon forests represent nearly half of all tropical vegetation biomass and, through photosynthesis and respiration, annually process more than twice the amount of estimated carbon (CO2) from fossil fuel emissions. Yet the seasonality of Amazon canopy cover, and the extent to which seasonal fluctuations in water availability and photosynthetically active radiation influence these processes, is still poorly understood. Implementing six remotely sensed data sets spanning nine years (2003-2011), with reported field and flux tower data, we show that southern equatorial Amazon forests exhibit a distinctive seasonal signal. Seasonal timing of water availability, canopy biomass growth and net leaf flush are asynchronous in regions with short dry seasons and become more synchronous across a west-to-east longitudinal moisture gradient of increasing dry season length. Forest cover is responsive to seasonal disparities in both water and solar radiation availability, temporally adjusting net leaf flush to maximize use of these generally abundant resources, while reducing drought susceptibility. An accurate characterization of this asynchronous behavior allows for improved understanding of canopy phenology across contiguous tropical forests and their sensitivity to climate variability and drought. These insights can also inform land surface models to provide a more accurate representation of seasonal forest carbon allocation strategies responsive to environmental drivers.
Full Text Available With the major advances of the Internet throughout the past couple of years, websites have come to play a central role in the modern marketing business program. However, simply owning a website is not enough for a business to prosper on the Web. Indeed, it is the level of usability of a website that determines if a user stays or abandons it for another competing one. It is therefore crucial to understand the importance of usability on the web, and consequently the need for its evaluation. Nonetheless, there exist a number of obstacles preventing software organizations from successfully applying sound website usability evaluation strategies in practice. From this point of view automation of the latter is extremely beneficial, which not only assists designers in creating more usable websites, but also enhances the Internet users’ experience on the Web and increases their level of satisfaction. As a means of addressing this problem, an Intelligent Usability Evaluation (IUE tool is proposed that automates the usability evaluation process by employing a Heuristic Evaluation technique in an intelligent manner through the adoption of several research-based AI methods. Experimental results show there exists a high correlation between the tool and human annotators when identifying the considered usability violations.
Baetens, J.M.; Van der Weeën, P.; De Baets, B.
Highlights: ► An upper bound on the Lyapunov exponent of asynchronously updated CA is established. ► The employed update method has repercussions on the stability of CAs. ► A decision on the employed update method should be taken with care. ► Substantial discrepancies arise between synchronously and asynchronously updated CA. ► Discrepancies between different asynchronous update schemes are less pronounced. - Abstract: Although cellular automata (CAs) were conceptualized as utter discrete mathematical models in which the states of all their spatial entities are updated simultaneously at every consecutive time step, i.e. synchronously, various CA-based models that rely on so-called asynchronous update methods have been constructed in order to overcome the limitations that are tied up with the classical way of evolving CAs. So far, only a few researchers have addressed the consequences of this way of updating on the evolved spatio-temporal patterns, and the reachable stationary states. In this paper, we exploit Lyapunov exponents to determine to what extent the stability of the rules within a family of totalistic CAs is affected by the underlying update method. For that purpose, we derive an upper bound on the maximum Lyapunov exponent of asynchronously iterated CAs, and show its validity, after which we present a comparative study between the Lyapunov exponents obtained for five different update methods, namely one synchronous method and four well-established asynchronous methods. It is found that the stability of CAs is seriously affected if one of the latter methods is employed, whereas the discrepancies arising between the different asynchronous methods are far less pronounced and, finally, we discuss the repercussions of our findings on the development of CA-based models.
V. S. Safaryan
Full Text Available The article considers experimental and analytical determination of the asynchronous machine equivalent-circuit parameters with application of the reference data. Transient processes investigation of the asynchronous machines necessitates the equivalent circuit parameters (resistance impedance, inductances and coefficient of the stator-rotor contours mutual inductance that help form the transitory-process mathematical simulation model. The reference books do not provide those parameters; they instead give the rated ones (active power, voltage, slide, coefficient of performance and capacity coefficient as well as the ratio of starting and nominal currents and torques. The noted studies on the asynchronous machine equivalent-circuits parametrization fail to solve the problems ad finem or solve them with admissions. The paper presents experimental and analytical determinations of the asynchronous machine equivalent-circuit parameters: the experimental one based on the results of two measurements and the analytical one where the problem boils down to solving a system of nonlineal algebraic equations. The authors investigate the equivalent asynchronous machine input-resistance properties and adduce the dependence curvatures of the input-resistances on the slide. They present a symbolic model for analytical parameterization of the asynchronous machine equivalent-circuit that represents a system of nonlineal equations and requires one of the rotor-parameters arbitrary assignment. The article demonstrates that for the asynchronous machine equivalent-circuit experimental parameterization the measures are to be conducted of the stator-circuit voltage, current and active power with two different slides and arbitrary assignment of one of the rotor parameters. The paper substantiates the fact that additional measurement does not discard the rotor-parameter choice arbitrariness. The authors establish that in motoring mode there is a critical slide by which the
Sparks, Randall; Hartson, Rex
The work we report on here addresses the problem of low return on investment in software usability engineering and offers support for usability practitioners in identifying, understanding, documenting...
Organizational usability is about the match between the user and the system, between the organization and the system, and between the environment and the system. While the first of these matches can, to a large extent, be evaluated in the lab, the two others cannot. Organizational usability must......, provide a brief example, and discuss the challenges it presents. To strengthen the focus on evaluation in the three contexts we propose the measurement of specified effects, combined with a sensitivity toward emergent effects. Incorporating effects in the evaluation of organizational usability makes...
Elnikety, Eslam Mohamed Ibrahim
MapReduce is a distributed programming frame-work designed to ease the development of scalable data-intensive applications for large clusters of commodity machines. Most machine learning and data mining applications involve iterative computations over large datasets, such as the Web hyperlink structures and social network graphs. Yet, the MapReduce model does not efficiently support this important class of applications. The architecture of MapReduce, most critically its dataflow techniques and task scheduling, is completely unaware of the nature of iterative applications; tasks are scheduled according to a policy that optimizes the execution for a single iteration which wastes bandwidth, I/O, and CPU cycles when compared with an optimal execution for a consecutive set of iterations. This work presents iHadoop, a modified MapReduce model, and an associated implementation, optimized for iterative computations. The iHadoop model schedules iterations asynchronously. It connects the output of one iteration to the next, allowing both to process their data concurrently. iHadoop\\'s task scheduler exploits inter-iteration data locality by scheduling tasks that exhibit a producer/consumer relation on the same physical machine allowing a fast local data transfer. For those iterative applications that require satisfying certain criteria before termination, iHadoop runs the check concurrently during the execution of the subsequent iteration to further reduce the application\\'s latency. This paper also describes our implementation of the iHadoop model, and evaluates its performance against Hadoop, the widely used open source implementation of MapReduce. Experiments using different data analysis applications over real-world and synthetic datasets show that iHadoop performs better than Hadoop for iterative algorithms, reducing execution time of iterative applications by 25% on average. Furthermore, integrating iHadoop with HaLoop, a variant Hadoop implementation that caches
Elnikety, Eslam Mohamed Ibrahim; El Sayed, Tamer S.; Ramadan, Hany E.
MapReduce is a distributed programming frame-work designed to ease the development of scalable data-intensive applications for large clusters of commodity machines. Most machine learning and data mining applications involve iterative computations over large datasets, such as the Web hyperlink structures and social network graphs. Yet, the MapReduce model does not efficiently support this important class of applications. The architecture of MapReduce, most critically its dataflow techniques and task scheduling, is completely unaware of the nature of iterative applications; tasks are scheduled according to a policy that optimizes the execution for a single iteration which wastes bandwidth, I/O, and CPU cycles when compared with an optimal execution for a consecutive set of iterations. This work presents iHadoop, a modified MapReduce model, and an associated implementation, optimized for iterative computations. The iHadoop model schedules iterations asynchronously. It connects the output of one iteration to the next, allowing both to process their data concurrently. iHadoop's task scheduler exploits inter-iteration data locality by scheduling tasks that exhibit a producer/consumer relation on the same physical machine allowing a fast local data transfer. For those iterative applications that require satisfying certain criteria before termination, iHadoop runs the check concurrently during the execution of the subsequent iteration to further reduce the application's latency. This paper also describes our implementation of the iHadoop model, and evaluates its performance against Hadoop, the widely used open source implementation of MapReduce. Experiments using different data analysis applications over real-world and synthetic datasets show that iHadoop performs better than Hadoop for iterative algorithms, reducing execution time of iterative applications by 25% on average. Furthermore, integrating iHadoop with HaLoop, a variant Hadoop implementation that caches
Boothe, Chase; Strawderman, Lesley; Hosea, Ethan
Inconsistencies among testing methods and results in previous research prompted this study that builds upon a systematic usability testing research framework to better understand how interface medium influences users' abilities to detect usability flaws in applications. Interface medium was tested to identify its effects on users' perceptions of usability and abilities to detect usability problems and severe usability problems. Results indicated that medium has no effect on users' abilities to detect usability problems or perceptions of usability. However, results did indicate an interaction between the medium and the tested application in which users were able to identify significantly more usability problems on a higher fidelity medium using a particular application. Results also indicated that as users' perceptions of an application's usability increases, the users are less able to detect usability problems in that application. Usability testing should begin early in the design process, even if low fidelity mediums will be used. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Bruun, Anders; Jensen, Janne Jul; Skov, Mikael B.
This report presents the results of a usability evaluation of the budget.com website. The evaluation was carried out by a team of 4 HCI experts, and it involved 10 potential users. The evaluation is based on measurement of (1) task completion time, (2) task completion, (3) user satisfaction and (4......) perceived workload. We have also analyzed the user interaction with the website for (5) usability problems. Through the evaluation, we have found the following weaknesses of the website: Reservation takes considerably more time than promised. The website indicates that a reservation can be made in 60...... is not useful for specific purposes. The user satisfaction is generally low. Except one high and two low scores, the user satisfaction was in the middle range. There are too many severe usability problems. The evaluation identified a considerable number of usability problems. 5 of them were critical which means...
Wale-Kolade, Adeola; Nielsen, Peter Axel
In this article we report from a case study of a software development organization and we study in particular the developers’ and product managers’ attitudes towards integrating usability work into software development. We offer explanations based on system justification theory illuminating what...... would-be integrators might be up against. The analysis shows how the developers only pay lip service to usability work and how they treat users superficially. It further shows how that leads to stereotyping of usability designers and users in order to preserve status quo, and how internalization...... of inequality between the developers and usability designers rationalizes the preservation of status quo. These findings will have significant implications for managers of software development....
Usability tests are conducted to gauge users’ experience with a system, preferably before it is released for real use, and thereby find any problems that prevent users from completing their tasks, slow them down, or otherwise degrade their user experience. Such tests are important to successful...... systems development, yet test procedures vary and the quality of test results is sometimes contested. While there is no single accepted procedure for usability specialists to follow when conducting usability tests, these tests normally involve users who think out loud while using a system and an evaluator...... who observes the users’ behavior and listens in on their thoughts. This common core of usability tests is illustrated in Figure 1. The possible variations include, for example, whether the users work individually or in pairs, whether the evaluator is in the room with the user or in an adjoining room...
Zhang, S.; Moore, A. B.
Virtual reality (VR) technology is starting to become widely and freely available (for example the online OpenSimulator tool), with potential for use in 3D urban planning and design tasks but still needing rigorous assessment to establish this. A previous study consulted with a small group of urban professionals, who concluded in a satisfaction usability test that online VR had potential value as a usable 3D communication and remote marketing tool but acknowledged that visual quality and geographic accuracy were obstacles to overcome. This research takes the investigation a significant step further to also examine the usability aspects of efficiency (how quickly tasks are completed) and effectiveness (how successfully tasks are completed), relating to OpenSimulator in an urban planning situation. The comparative study pits a three-dimensional VR model (with increased graphic fidelity and geographic content to address the feedback of the previous study) of a subdivision design (in a Dunedin suburb) against 3D models built with GIS (ArcGIS) and CAD (BricsCAD) tools, two types of software environment well established in urban professional practice. Urban professionals participated in the study by attempting to perform timed tasks correctly in each of the environments before being asked questions about the technologies involved and their perceived importance to their professional work. The results reinforce the positive feedback for VR of the previous study, with the graphical and geographic data issues being somewhat addressed (though participants stressed the need for accurate and precise object and terrain modification capabilities in VR). Ease-ofuse and associated fastest task completion speed were significant positive outcomes to emerge from the comparison with GIS and CAD, pointing to a strong future for VR in an urban planning context.
Van Kuijk, J.I.
Problem statement: Even though there is a large amount of methods for user-centred design, the usability of electronic consumer products (e.g., portable music players, washing machines and mobile phones) is under pressure. Usability is the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use. That the usability of electronic consumer products is under pressure is attributed to an incre...
Peters, Vanessa L.; Songer, Nancy Butler
This paper reports the results of a three-stage usability test of a modeling tool designed to support learners' deep understanding of the impacts of climate change on ecosystems. The design process involved repurposing an existing modeling technology used by professional scientists into a learning tool specifically designed for middle school students. To evaluate usability, we analyzed students' task performance and task completion time as they worked on an activity with the repurposed modeling technology. In stage 1, we conducted remote testing of an early modeling prototype with urban middle school students (n = 84). In stages 2 and 3, we used screencasting software to record students' mouse and keyboard movements during collaborative think-alouds (n = 22) and conducted a qualitative analysis of their peer discussions. Taken together, the study findings revealed two kinds of usability issues that interfered with students' productive use of the tool: issues related to the use of data and information, and issues related to the use of the modeling technology. The study findings resulted in design improvements that led to stronger usability outcomes and higher task performance among students. In this paper, we describe our methods for usability testing, our research findings, and our design solutions for supporting students' use of the modeling technology and use of data. The paper concludes with implications for the design and study of modeling technologies for science learning.
Sabel, Laura; Marzullo, Keith
The fail-stop failure model appears frequently in the distributed systems literature. However, in an asynchronous distributed system, the fail-stop model cannot be implemented. In particular, it is impossible to reliably detect crash failures in an asynchronous system. In this paper, we show that it is possible to specify and implement a failure model that is indistinguishable from the fail-stop model from the point of view of any process within an asynchronous system. We give necessary conditions for a failure model to be indistinguishable from the fail-stop model, and derive lower bounds on the amount of process replication needed to implement such a failure model. We present a simple one-round protocol for implementing one such failure model, which we call simulated fail-stop.
Wang, Yanlong; Li, Zhanhuai; Lin, Wei; Hei, Minglei; Hao, Jianhua
Data replication is a key way to design a disaster tolerance system and to achieve reliability and availability. It is difficult for a replication protocol to deal with the diverse and complex environment. This means that data is less well replicated than it ought to be. To reduce data loss and to optimize replication protocols, we (1) present a finite state machine, (2) run it to manage an asynchronous replication protocol and (3) report a simple evaluation of the asynchronous replication protocol based on our state machine. It's proved that our state machine is applicable to guarantee the asynchronous replication protocol running in the proper state to the largest extent in the event of various possible events. It also can helpful to build up replication-based disaster tolerance systems to ensure the business continuity.
Ferrari, Ester; Cavallo, Eugenio
Teleoperation has been widely applied in modern industry because of a variety of advantages, such as providing replaceable surrogates for humans in dangerous or difficult working environments over long distances. In this paper, a usability evaluation study of a teleoperation system for a compost spreader robotic machine is presented. The machine has been designed for the application of compost in small and stepping parcels of hilly vineyards. Driving and working tasks can be controlled remotely by a portable piloting unit, reducing the risk for the operator in the event of machine overturning. Participants of the study were asked to perform a series of tasks and sub-tasks and to vocalize their thoughts while working with the machine. The tasks were designed to simulate typical user experience. Once all the tasks were accomplished each participant was asked to fill a questionnaire. The evaluation considered aspects such as learnability, ease of use, understandability, controllability, frustration, mental effort, distraction, clarity of presentation, perceived usefulness, temporal efficiency and machine aesthetic. Results show that usability evaluation helped detecting design deficiencies in the teleoperated compost spreader machine.
Luis Marco Cáceres Alvarez
Full Text Available El presente trabajo define y detalla un modelo de programación asíncrono para sistemas de información Web transaccionales orientado a servicios en un ambiente distribuido uniendo las ventajas de las técnicas de programación Web asíncronas (AJAX, patrones de diseño orientados a objetos y servicios Web, para la obtención de aplicativos caracterizados por ser tolerantes a fallos, distribuidos, eficientes y usables. Principalmente se puntualizan los problemas encontrados en el modelo para uso de servicios Web clásicos, por ende se define, documenta y desarrolla un modelo de programación que solucione y mejore los servicios Web clásicos y se valide la solución a través del desarrollo de un prototipo basado en el modelo de programación definido.The present work defines and details an asynchronous programming model for transactional web information systems in distributed environment, joining the advantages of web asynchronous programming techniques (AJAX, object oriented design patterns and web services, to obtain fail tolerant, distributed, efficient and usable applications. The problems found in the classical Web services model are pointed out and a new model to solve and improve most common web services is defined, documented and developed. Also, a prototype is developed to validate the given solution using the defined model.
Batbaatar, Jigjidsurengiin; Gillespie, Alan R.; Fink, David; Matmon, Ari; Fujioka, Toshiyuki
Mountain glaciers at ∼26-19 ka, during the global Last Glacial Maximum near the end of the last 105 yr glacial cycle, are commonly considered on the basis of dating and field mapping in several well-studied areas to have been the largest of the late Quaternary and to have advanced synchronously from region to region. However, a numerical sensitivity model (Rupper and Roe, 2008) predicts that the fraction of ablation due to melting varies across Central Asia in proportion to the annual precipitation. The equilibrium-line altitude of glaciers across this region likely varies accordingly: in high altitude, cold and arid regions sublimation can ablate most of the ice, whereas glaciers fed by high precipitation cannot ablate completely due to sublimation alone, but extend downhill until higher temperatures there cause them to melt. We have conducted field studies and 10Be dating at five glaciated sites along a precipitation gradient in Mongolia to test the Rupper/Roe model. The sites are located in nearby 1.875 × 1.875° cells of the Rupper/Roe model, each with a different melt fraction, in this little-studied region. The modern environment of the sites ranges from dry subhumid in the north (47.7° N) to arid in the south (45° N). Our findings show that the maximum local advances in the dry subhumid conditions predated the global Last Glacial Maximum and were likely from MIS 3. However, we also found that at ∼8-7 ka a cirque glacier in one mountain range of the arid Gobi desert grew to a magnitude comparable to that of the local maximum extent. This Holocene maximum occurred during a regional pluvial period thousands of years after the retreat of the Pleistocene glaciers globally. This asynchronous behavior is not predicted by the prevailing and generally correct presumption that glacier advances are dominantly driven by temperature, although precipitation also plays a role. Our findings are consistent with and support the Rupper/Roe model, which calls for
Tamara Gilbson Kolda
In this paper the authors prove global convergence for asynchronous parallel pattern search. In standard pattern search, decisions regarding the update of the iterate and the step-length control parameter are synchronized implicitly across all search directions. They lose this feature in asynchronous parallel pattern search since the search along each direction proceeds semi-autonomously. By bounding the value of the step-length control parameter after any step that produces decrease along a single search direction, they can prove that all the processes share a common accumulation point and that such a point is a stationary point of the standard nonlinear unconstrained optimization problem
Du, Xue; Ye, Ying; Wang, Yuelong; Peng, Lei; Zhang, Suying
The starting way of three phase asynchronous motor has full voltage start and step-down start. Direct starting brings large current impact, causing excessive local temperature to the power grid and larger starting torque will also impact the motor equipment and affect the service life of the motor. Aim at the problem of large current and torque caused by start-up, an intelligent soft starter is proposed. Through the application of intelligent soft start on asynchronous motor, highlights its application advantage in motor control.
Full Text Available The paper sets out the methodology of designing an asynchronous generator with capacitive self-excitation. It is known that its design is possible on the basis of serial synchronous motor with squirrel cage rotor. With this approach, the design reworked only the stator winding of electrical machines, making it cost-effectively implement the creation of the generator. Therefore, the methodology for the design, optimization calculations, the development scheme and the stator winding excitation system gain, not only of practical interest, and may also be useful for specialists in the field of electrical machines in the design of asynchronous generators.
Lee, Jia; Adachi, Susumu; Peper, Ferdinand
We propose a self-replicating machine that is embedded in a two-dimensional asynchronous cellular automaton with von Neumann neighborhood. The machine dynamically encodes its shape into description signals, and despite the randomness of cell updating, it is able to successfully construct copies of itself according to the description signals. Self-replication on asynchronously updated cellular automata may find application in nanocomputers, where reconfigurability is an essential property, since it allows avoidance of defective parts and simplifies programming of such computers.
Beerliová-Trubíniová, Zuzana; Hirt, Martin; Nielsen, Jesper Buus
that in the cryptographic setting (with setup), the sole reason for it is the distribution of inputs: given an oracle for input distribution, cryptographically-secure asynchronous MPC is possible with the very same condition as synchronous MPC, namely t ..., we show that such an input-distribution oracle can be reduced to an oracle that allows each party to synchronously broadcast one single message. This means that when one single round of synchronous broadcast is available, then asynchronous MPC is possible at the same condition as synchronous MPC...
Olivier, Stephen L.
The asynchronous task model serves as a useful vehicle for shared memory parallel programming, particularly on multicore and manycore processors. As adoption of model among programmers has increased, support has emerged for the integration of task parallel language constructs into mainstream programming languages, e.g., C and C++. This paper examines some of the design decisions in Cilk and OpenMP concerning semantics and scheduling of asynchronous tasks with the aim of informing the efforts of committees considering language integration, as well as developers of new task parallel languages and libraries.
When digital tools are developed it is important to consider the usability of the tool. Usability evaluation was done on the Afrikaanse idiome-woordeboek to determine with what success it can be used. Discount usability methods, viz. heuristic evaluation and usability testing were used. This article reports on the findings from ...
Lahtinen, J.; Launiainen, T.; Heljanko, K.; Ropponen, J.
Digital instrumentation and control (I and C) systems are challenging to verify. They enable complicated control functions, and the state spaces of the models easily become too large for comprehensive verification through traditional methods. Model checking is a formal method that can be used for system verification. A number of efficient model checking systems are available that provide analysis tools to determine automatically whether a given state machine model satisfies the desired safety properties. This report reviews the work performed in the Safety Evaluation and Reliability Analysis of Nuclear Automation (SARANA) project in 2011 regarding model checking. We have developed new, more exact modelling methods that are able to capture the behaviour of a system more realistically. In particular, we have developed more detailed fault models depicting the hardware configuration of a system, and methodology to model function-block-based systems asynchronously. In order to improve the usability of our model checking methods, we have developed an algorithm for model checking large modular systems. The algorithm can be used to verify properties of a model that could otherwise not be verified in a straightforward manner. (orig.)
Lahtinen, J. [VTT Technical Research Centre of Finland, Espoo (Finland); Launiainen, T.; Heljanko, K.; Ropponen, J. [Aalto Univ., Espoo (Finland). Dept. of Information and Computer Science
Digital instrumentation and control (I and C) systems are challenging to verify. They enable complicated control functions, and the state spaces of the models easily become too large for comprehensive verification through traditional methods. Model checking is a formal method that can be used for system verification. A number of efficient model checking systems are available that provide analysis tools to determine automatically whether a given state machine model satisfies the desired safety properties. This report reviews the work performed in the Safety Evaluation and Reliability Analysis of Nuclear Automation (SARANA) project in 2011 regarding model checking. We have developed new, more exact modelling methods that are able to capture the behaviour of a system more realistically. In particular, we have developed more detailed fault models depicting the hardware configuration of a system, and methodology to model function-block-based systems asynchronously. In order to improve the usability of our model checking methods, we have developed an algorithm for model checking large modular systems. The algorithm can be used to verify properties of a model that could otherwise not be verified in a straightforward manner. (orig.)
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Brinkman, W.P.; Haakma, R.; Bouwhuis, D.G.; Bastide, R.; Palanque, P.; Roth, J.
This paper addresses the issue of usability testing in a component-based software engineering environment, specifically measuring the usability of different versions of a component in a more powerful manner than other, more holistic, usability methods. Three component-specific usability measures are
Hendradewa, Andrie Pasca
Usability is a key factor that determine success of a product or interactive system, like smartphone. The increasing use of smartphone and its rapid technology development, requires usability evaluation method that is more accurate and effective to found usability problem, so it can be used for product improvement in development process. This study suggests a usability evaluation method that is most effective to identify problem in smartphone usage. Three usability evaluation methods that com...
Van Kuijk, J.I.
Problem statement: Even though there is a large amount of methods for user-centred design, the usability of electronic consumer products (e.g., portable music players, washing machines and mobile phones) is under pressure. Usability is the extent to which a product can be used by specified users to
Marcilly, Romaric; Peute, Linda; Beuscart-Zephir, Marie-Catherine
Usability is a critical factor in the acceptance, safe use, and success of health IT. The User-Centred Design process is widely promoted to improve usability. However, this traditional case by case approach that is rooted in the sound understanding of users' needs is not sufficient to improve
In ziekenhuizen wordt steeds meer gebruik gemaakt van informatiesystemen, maar de usability laat vaak te wensen over. Reza Khajouei testte twee methodes om de usability te beoordelen. Hij constateert dat beide methoden ongeveer evenveel, maar verschillende problemen aan het licht brengen. Uit een
Web mapping sites are interactive maps that are accessed via Webpages. With the rapid development of Internet and Geographic Information System (GIS) field, public web mapping sites are not foreign to people. Nowadays, people use these web mapping sites for various reasons, in that increasing maps and related map services of web mapping sites are freely available for end users. Thus, increased users of web mapping sites led to more usability studies. Usability Engineering (UE), for instance, is an approach for analyzing and improving the usability of websites through examining and evaluating an interface. In this research, UE method was employed to explore usability problems of four public web mapping sites, analyze the problems quantitatively and provide guidelines for future design based on the test results. Firstly, the development progress for usability studies were described, and simultaneously several usability evaluation methods such as Usability Engineering (UE), User-Centered Design (UCD) and Human-Computer Interaction (HCI) were generally introduced. Then the method and procedure of experiments for the usability test were presented in detail. In this usability evaluation experiment, four public web mapping sites (Google Maps, Bing maps, Mapquest, Yahoo Maps) were chosen as the testing websites. And 42 people, who having different GIS skills (test users or experts), gender (male or female), age and nationality, participated in this test to complete the several test tasks in different teams. The test comprised three parts: a pretest background information questionnaire, several test tasks for quantitative statistics and progress analysis, and a posttest questionnaire. The pretest and posttest questionnaires focused on gaining the verbal explanation of their actions qualitatively. And the design for test tasks targeted at gathering quantitative data for the errors and problems of the websites. Then, the results mainly from the test part were analyzed. The
Van Nuland, Sonya E; Eagleson, Roy; Rogers, Kem A
Online educational technologies and e-learning tools are providing new opportunities for students to learn worldwide, and they continue to play an important role in anatomical sciences education. Yet, as we shift to teaching online, particularly within the anatomical sciences, it has become apparent that e-learning tool success is based on more than just user satisfaction and preliminary learning outcomes-rather it is a multidimensional construct that should be addressed from an integrated perspective. The efficiency, effectiveness and satisfaction with which a user can navigate an e-learning tool is known as usability, and represents a construct which we propose can be used to quantitatively evaluate e-learning tool success. To assess the usability of an e-learning tool, usability testing should be employed during the design and development phases (i.e., prior to its release to users) as well as during its delivery (i.e., following its release to users). However, both the commercial educational software industry and individual academic developers in the anatomical sciences have overlooked the added value of additional usability testing. Reducing learner frustration and anxiety during e-learning tool use is essential in ensuring e-learning tool success, and will require a commitment on the part of the developers to engage in usability testing during all stages of an e-learning tool's life cycle. Anat Sci Educ 10: 190-199. © 2016 American Association of Anatomists. © 2016 American Association of Anatomists.
Borycki, Elizabeth M; Monkman, Helen; Griffith, Janessa; Kushniruk, Andre W
The use of mobile devices and healthcare applications is increasing exponentially worldwide. This has lead to the need for the healthcare industry to develop a better understanding of the impact of the usability of mobile software and hardware upon consumer and health professional adoption and use of these technologies. There are many methodological approaches that can be employed in conducting usability evaluation of mobile technologies. More obtrusive approaches to collecting study data may lead to changes in study participant behaviour, leading to study results that are less consistent with how the technologies will be used in the real-world. Alternatively, less obstrusive methods used in evaluating the usability of mobile software and hardware in-situ and laboratory settings can lead to less detailed information being collected about how an individual interacts with both the software and hardware. In this paper we review and discuss several innovative mobile usability evaluation methods on a contiuum from least to most obtrusive and their effects on the quality of the usability data collected. The strengths and limitations of methods are also discussed.
Glenn, Cynthia Wheatley
For learners to actively accept responsibility in a virtual classroom platform, it is necessary to provide special motivation extending across the traditional classroom setting into asynchronous online learning. This article explores specific ways to do this that bridge the gap between ground and online students' learning experiences, and how…
Larbi-Siaw, Otu; Owusu-Agyeman, Yaw
This study investigates the determinants of students' satisfaction in an asynchronous learning environment using seven key considerations: the e-learning environment, student-content interaction, student and student interaction, student-teacher interaction, group cohesion and timely participation, knowledge of Internet usage, and satisfaction. The…
The conventional method of analysis of Asynchronous machine fails to give accurate results especially when the machine is operated under high rotor frequency. At high rotor frequency, skin-effect dominates causing the rotor impedance to be frequency dependant. This paper therefore presents an improved method of ...
Purpose: Researchers commonly utilize coding-based analysis of classroom asynchronous discussion contributions as part of studies of online learning and instruction. However, this analysis is inconsistent from study to study with over 50 coding schemes and procedures applied in the last eight years. The aim of this article is to provide a basis…
Vlachopoulos, Panos; Cowan, John
This article reports a grounded theory study of the moderation of asynchronous online discussions, to explore the processes by which tutors in higher education decide when and how to moderate. It aims to construct a theory of e-moderation based on some key factors which appear to influence e-moderation. It discusses previous research on the…
Downey, W. Scott; Schetzsle, Stacey
Asynchronous assessment, which includes quizzes or exams online or outside class, offers marketing educators an opportunity to make more efficient use of class time and to enhance students' learning experiences by giving them more flexibility and choice in their assessment environment. In this paper, we examine the performance difference between…
Saeed, Murad Abdu; Ghazali, Kamila
The current paper reports an empirical study of asynchronous online group review of argumentative essays among nine English as foreign language (EFL) Arab university learners joining English in their first, second, and third years at the institution. In investigating online interactions, commenting patterns, and how the students facilitate text…
Leporati, Alberto; Manzoni, Luca; Porreca, Antonio E.
We prove that asynchronous P systems with active membranes without divi- sion rules can be simulated by place/transition Petri nets, and hence are computationally weaker than Turing machines. This result holds even if the synchronisation mechanisms provided by electrical charges and membrane dissolution are exploited.
David N. Bengston; Robert L. Olson
Text-based asynchronous online conferencing involves structured online discussion and deliberation among multiple participants from multiple sites in which there is a delay in interaction between contributors. This method has been widely used for a variety of purposes in higher education and other settings, but has not been commonly used in futures research. This paper...
Doğan, Seda; Tusha, Armed; Arslan, Hüseyin
One of the critical missions for next-generation wireless communication systems is to fulfill the high demand for massive Machine-Type Communications (mMTC). In mMTC systems, a sporadic transmission is performed between machine users and base station (BS). Lack of coordination between the users and BS in time destroys orthogonality between the subcarriers, and causes inter-carrier interference (ICI). Therefore, providing services to asynchronous massive machine users is a major challenge for Orthogonal Frequency Division Multiplexing (OFDM). In this study, OFDM with index modulation (OFDM-IM) is proposed as an eligible solution to alleviate ICI caused by asynchronous transmission in uncoordinated mMTC networks. In OFDM-IM, data transmission is performed not only by modulated subcarriers but also by the indices of active subcarriers. Unlike classical OFDM, fractional subcarrier activation leads to less ICI in OFDM-IM technology. A novel subcarrier mapping scheme (SMS) named as Inner Subcarrier Activation is proposed to further alleviate adjacent user interference in asynchronous OFDM-IM-based systems. ISA reduces inter-user interference since it gives more activation priority to inner subcarriers compared with the existing SMS-s. The superiority of the proposed SMS is shown through both theoretical analysis and computer-based simulations in comparison to existing mapping schemes for asynchronous systems.
Teaching an online fully asynchronous information technology course that requires students to ideate, build an e-commerce website, and develop an effective business plan involves a well-developed and highly engaging course design. This paper describes the design, development, and implementation of such a course and presents information on…
The signals generated by the micro controller have been used to program the parallel port of a computer. By reading the recorded bits of the parallel port in LabVIEW software, the signals from the micro controller have been restored and made available to the simulation model of the three-phase inverter, asynchronous ...
Karandey, V. Yu; Popov, B. K.; Popova, O. B.; Afanasyev, V. L.
The article considers the solution of the problem of parameters optimization of special asynchronous electric drives. The solution of the problem will allow one to project and create special asynchronous electric drives for various industries. The created types of electric drives will have optimum mass-dimensional and power parameters. It will allow one to realize and fulfill the set characteristics of management of technological processes with optimum level of expenses of electric energy, time of completing the process or other set parameters. The received decision allows one not only to solve a certain optimizing problem, but also to construct dependences between the optimized parameters of special asynchronous electric drives, for example, with the change of power, current in a winding of the stator or rotor, induction in a gap or steel of magnetic conductors and other parameters. On the constructed dependences, it is possible to choose necessary optimum values of parameters of special asynchronous electric drives and their components without carrying out repeated calculations.
Boudt, Kris; Laurent, Sébastien; Lunde, Asger
An estimator of the ex-post covariation of log-prices under asynchronicity and microstructure noise is proposed. It uses the Cholesky factorization of the covariance matrix in order to exploit the heterogeneity in trading intensities to estimate the different parameters sequentially with as many...
Boudt, Kris; Laurent, Sébastien; Lunde, Asger
An estimator of the ex-post covariation of log-prices under asynchronicity and microstructure noise is proposed. It uses the Cholesky factorization on the correlation matrix in order to exploit the heterogeneity in trading intensity to estimate the different parameters sequentially with as many...
Zobrist, Kevin W.
Asynchronous online Extension classes can reach a wide audience, is convenient for the learner, and minimizes ongoing demands on instructor time. However, producing such classes takes significant effort up front. Advance planning and good communication with contributors are essential to success. Considerations include delivery platforms, content…
Rajanen, Dorina; Clemmensen, Torkil; Iivari, Netta
This paper examines the views of user experience (UX) professionals on the definitions of usability and UX, and compares the findings between countries and within different socio-cultural groups. A mixed-method analysis was employed on data gathered on 422 professionals through a survey in Turkey......, Finland, Denmark, France, and Malaysia. Usability appears to be an established concept, respondents across all countries agreeing on the importance of the ISO 9241-11 definition. There is also a tendency that UX professionals attach organizational perspective to usability. UX professionals diverge when...... defining UX, and there are systematic differences related to socio-cultural conditions. UX professionals in Finland and France incline more towards the definition highlighting the experiential qualities, when compared to Turkey and Malaysia that incline towards the definition reflecting the ease of use...
There are indications that established methods for evaluating information system usability that have been developed for use in, e.g. Europe or the USA, fail to give reliable results in countries such as India, China or Malaysia. This paper presents the theoretical background, related work...... and a definition of culture that should be useful for studies of multiple-country usability testing. This includes a discussion of cultural fit and the consequences of cultural (in)consistencies between stakeholders in system development and use. As an illustrative example of the kind of academic research...... that needs to be done, a pilot study is described. The pilot study exemplifies themes to explore, who should be participants and where should the study be done, how to find examples of multiple-country usability testing, how to collect data and how to analyse that data and what kind of results and discussion...
This paper focuses on the use of remote sensing for marine oil spill detection and response. The surveillance and monitoring of discharges, and the main elements of effective surveillance are discussed. Tactical emergency response and the requirements for selecting a suitable remote sensing approach, airborne remote sensing systems, and the integration of satellite and airborne imaging are examined. Specifications of satellite surveillance systems potentially usable for oil spill detection, and specifications of airborne remote sensing systems suitable for oil spill detection, monitoring and supplemental actions are tabulated, and a schema of integrated satellite-airborne remote sensing (ISARS) is presented. (UK)
I. What is usability and why should I care?A. Overview chapter Isbister and Schaffer (Editors)Introduces key concepts and positions book for primary audiences: game developers andstudents aspiring to work in game development. Addresses key concerns that developersmay have about adopting usability, and sets a broad road map of what is to come in thebook.B. Interview with Tobi Saulnier of 1st PlayableA discussion with the CEO of a small game studio about why and how she uses usabilitytechniques in her development.C. Interview with Don Norman of Nielsen Norman groupA discussion with one of the pr
Larsen, Lars Bo
This work is centred on the methods and problems associated with defining and measuring the usability of Spoken Dialogue Systems (SDS). The starting point is the fact that speech based interfaces has several times during the last 20 years fallen short of the high expectations and predictions held...... by industry, researchers and analysts. Several studies in the literature of SDS indicate that this can be ascribed to a lack of attention from the speech technology community towards the usability of such systems. The experimental results presented in this work are based on a field trial with the OVID home...
Many natural and engineering systems are governed by nonlinear partial differential equations (PDEs) which result in a multiscale phenomena, e.g. turbulent flows. Numerical simulations of these problems are computationally very expensive and demand for extreme levels of parallelism. At realistic conditions, simulations are being carried out on massively parallel computers with hundreds of thousands of processing elements (PEs). It has been observed that communication between PEs as well as their synchronization at these extreme scales take up a significant portion of the total simulation time and result in poor scalability of codes. This issue is likely to pose a bottleneck in scalability of codes on future Exascale systems. In this work, we propose an asynchronous computing algorithm based on widely used finite difference methods to solve PDEs in which synchronization between PEs due to communication is relaxed at a mathematical level. We show that while stability is conserved when schemes are used asynchronously, accuracy is greatly degraded. Since message arrivals at PEs are random processes, so is the behavior of the error. We propose a new statistical framework in which we show that average errors drop always to first-order regardless of the original scheme. We propose new asynchrony-tolerant schemes that maintain accuracy when synchronization is relaxed. The quality of the solution is shown to depend, not only on the physical phenomena and numerical schemes, but also on the characteristics of the computing machine. A novel algorithm using remote memory access communications has been developed to demonstrate excellent scalability of the method for large-scale computing. Finally, we present a path to extend this method in solving complex multi-scale problems on Exascale machines.
Full Text Available The subject of the research is software usability and the aim is construction of mathematicalmodel of estimation and providing of the set level of usability. Methodology of structural analysis,methods of multicriterion optimization and theory of making decision, method of convolution,scientific methods of analysis and analogies is used in the research. The result of executed work isthe model for software usability automated evaluation and assurance that allows not only toestimate the current level of usability during every iteration of agile development but also tomanage the usability of created software products. Results can be used for the construction ofautomated support systems of management the software usability.
Nielsen, Lene; Madsen, Sabine
This paper contributes to the HCI literature on usability practice with insights about the empirical challenges and global emerging practices caused by the advent of agile software development (ASD). In the paper we report from a worldwide study involving 12 usability professionals from 12...... different countries. The findings show that the usability professionals share a forced development and innovation in their practice that stem from their clients’ adoption and use of ASD methods. The ASD methods challenge the way usability testing is performed, the abilities of the usability expert......, the usability deliverables, and the experts’ assumptions about the importance of validity....
Jiang, Y.; Sun, X.; Li, H.
in the study, their understanding of fun systems differs across cultural backgrounds. Also, easy-to-use and useful systems are perceived as being similar or different depending on the usability professional’s cultural background. Most other cross-cultural differences relate to categories of construct......Culture influences many aspects of the design and use of computer systems; understanding better this influence on their own thinking may benefit usability professionals who do cross-cultural usability work. Using Kelly’s notion of personal constructs, we focus on one mediator of culture: how...
Chan, Alvita J.; Islam, Mohammad K.; Rosewall, Tara; Jaffray, David A.; Easty, Anthony C.; Cafazzo, Joseph A.
Background and purpose: Heuristic evaluations have been used to evaluate safety of medical devices by identifying and assessing usability issues. Since radiotherapy treatment delivery systems often consist of multiple complex user-interfaces, a heuristic evaluation was conducted to assess the potential safety issues of such a system. Material and methods: A heuristic evaluation was conducted to evaluate the treatment delivery system at Princess Margaret Hospital (Toronto, Canada). Two independent evaluators identified usability issues with the user-interfaces and rated the severity of each issue. Results: The evaluators identified 75 usability issues in total. Eighteen of them were rated as high severity, indicating the potential to have a major impact on patient safety. A majority of issues were found on the record and verify system, and many were associated with the patient setup process. While the hospital has processes in place to ensure patient safety, recommendations were developed to further mitigate the risks of potential consequences. Conclusions: Heuristic evaluation is an efficient and inexpensive method that can be successfully applied to radiotherapy delivery systems to identify usability issues and improve patient safety. Although this study was conducted only at one site, the findings may have broad implications for the design of these systems.
Hultman, Gretchen; Marquard, Jenna; Arsoniadis, Elliot; Mink, Pamela; Rizvi, Rubina; Ramer, Tim; Khairat, Saif; Fickau, Keri; Melton, Genevieve B
Despite widespread electronic health record (EHR) adoption, poor EHR system usability continues to be a significant barrier to effective system use for end users. One key to addressing usability problems is to employ user testing and user-centered design. To understand if redesigning an EHR-based navigation tool with clinician input improved user performance and satisfaction. A usability evaluation was conducted to compare two versions of a redesigned ambulatory navigator. Participants completed tasks for five patient cases using the navigators, while employing a think-aloud protocol. The tasks were based on Meaningful Use (MU) requirements. The version of navigator did not affect perceived workload, and time to complete tasks was longer in the redesigned navigator. A relatively small portion of navigator content was used to complete the MU-related tasks, though navigation patterns were highly variable across participants for both navigators. Preferences for EHR navigation structures appeared to be individualized. This study demonstrates the importance of EHR usability assessments to evaluate group and individual performance of different interfaces and preferences for each design.
Bringula, Rex P.; Basa, Roselle S.
The study investigated the factors that might significantly affect web portal usability. Results of the study were intended to serve as inputs for faculty web portal development of the University of the East-Manila. Descriptive statistics utilized questionnaire data from 82 faculty members. The data showed that most of the respondents were…
Saad Masood Butt
Full Text Available Agile methods are the best fit for tremendously growing software industry due to its flexible and dynamic nature. But the software developed using agile methods do meet the usability standards? To answer this question we can see that majority of agile software development projects currently involve interactive user interface designs, which can only be possible by following User Centered Design (UCD in agile methods. The question here is, how to integrate UCD with agile models. Both Agile models and UCD are iterative in nature but agile models focus on coding and development of software; whereas, UCD focuses on user interface of the software. Similarly, both of them have testing features where the agile model involves automated tested code while UCD involves an expert or a user to test the user interface. In this paper, a new agile usability model is proposed and the evaluation is of the proposed model is presented by practically implementing it in three real life projects. . Key results from these projects clearly show: the proposed agile model incorporates usability evaluation methods, improves the relationship between usability experts to work with agile software experts; in addition, allows agile developers to incorporate the result from UCD into subsequent interactions.
Your next usability project could be waiting for you in the college library, registration office, or online admissions process that your college or university utilizes in their daily transactions. As an added bonus, these exercises supplement the IS2002 curriculum model, benefit the instructor's institution, build inter-departmental collaboration,…
Schmettow, Martin; Bach, Cedric; Scapin, Dominique
This paper examines combinations of complementary evaluation methods as a strategy for efficient usability problem discovery. A data set from an earlier study is re-analyzed, involving three evaluation methods applied to two virtual environment applications. Results of a mixed-effects logistic
Remote studies allow you to recruit subjects quickly, cheaply, and immediately, and give you the opportunity to observe users as they behave naturally in their own environment. In Remote Research, Nate Bolt and Tony Tulathimutte teach you how to design and conduct remote research studies, top to bottom, with little more than a phone and a laptop.
Dankert, James R; Olson, Byron; Si, Jennie
This paper presents a method for asynchronous decision making using recorded neural data in a binary decision task. This is a demonstration of a technique for developing motor cortical neural prosthetics that do not rely on external cued timing information. The system presented in this paper uses support vector machines and leaky integrate-and-fire elements to predict directional paddle presses. In addition to the traditional metrics of accuracy, asynchronous systems must also optimize the time needed to make a decision. The system presented is able to predict paddle presses with a median accuracy of 88% and all decisions are made before the time of the actual paddle press. An alternative bit rate measure of performance is defined to show that the system proposed here is able to perform the task with the same efficiency as the rats.
Jones, W. H.
The Parallel, Asynchronous Executive (PAX) is a software operating system simulation that allows many computers to work on a single problem at the same time. PAX is currently implemented on a UNIVAC 1100/42 computer system. Independent UNIVAC runstreams are used to simulate independent computers. Data are shared among independent UNIVAC runstreams through shared mass-storage files. PAX has achieved the following: (1) applied several computing processes simultaneously to a single, logically unified problem; (2) resolved most parallel processor conflicts by careful work assignment; (3) resolved by means of worker requests to PAX all conflicts not resolved by work assignment; (4) provided fault isolation and recovery mechanisms to meet the problems of an actual parallel, asynchronous processing machine. Additionally, one real-life problem has been constructed for the PAX environment. This is CASPER, a collection of aerodynamic and structural dynamic problem simulation routines. CASPER is not discussed in this report except to provide examples of parallel-processing techniques.
Full Text Available This paper introduces a plug-and-play on-chip asynchronous communication network aimed at the dynamic reconfiguration of a low-power adaptive circuit such as an internet of things (IoT system. By using a separate communication network, we can address both digital and analog blocks at a lower configuration cost, increasing the overall system power efficiency. As reconfiguration only occurs according to specific events and has to be automatically in stand-by most of the time, our design is fully asynchronous using handshake protocols. The paper presents the circuit’s architecture, performance results, and an example of the reconfiguration of frequency locked loops (FLL to validate our work. We obtain an overall energy per bit of 0.07 pJ/bit for one stage, in a 28 nm Fully Depleted Silicon On Insulator (FDSOI technology at 0.6 V and a 1.1 ns/bit latency per stage.
Bornoe, Nis; Stage, Jan
Despite an interest and use of different usability engineering methods small software development organizations find it challenging to implement usability engineering into the software development process. We present the results from a study about usability engineering in practice. Through a series...... of semistructured interviews we want to get an understanding of how usability is implemented into the organizations and how it’s practiced in reality. We found that the developers found it problematic to combine agile software development methods with classic usability engineering methods. A lack of solid usability...... engineering expertise and not least experience seems to be a main obstacle for a successful implementation of usability engineering into current software development practices. They are requesting methods and procedures that fit better with their current practices and strategies to implement usability...
Usability testing has evolved in response to a search for tests that are cheap, early, easy, and fast. In addition, it accords with a situational definition of usability, such as the one propounded by ISO. By approaching usability from an organizational perspective, this author argues that usabil......Usability testing has evolved in response to a search for tests that are cheap, early, easy, and fast. In addition, it accords with a situational definition of usability, such as the one propounded by ISO. By approaching usability from an organizational perspective, this author argues...... that usability should (also) be evaluated late, that usability professionals should be wary of thinking aloud, and that they should focus more on effects achievement than problem detection....
Markopoulos, P.; Bekker, M.M.
The paper motivates the need to acquire methodological knowledge for involving children as test users in usability testing. It introduces a methodological framework for delineating comparative assessments of usability testing methods for children participants. This framework consists in three
Khorram, Siamak; Koch, Frank H; van der Wiele, Cynthia F
Remote Sensing provides information on how remote sensing relates to the natural resources inventory, management, and monitoring, as well as environmental concerns. It explains the role of this new technology in current global challenges. "Remote Sensing" will discuss remotely sensed data application payloads and platforms, along with the methodologies involving image processing techniques as applied to remotely sensed data. This title provides information on image classification techniques and image registration, data integration, and data fusion techniques. How this technology applies to natural resources and environmental concerns will also be discussed.
Brenda M Scholtz
Full Text Available Though the field of management information systems, as a sector and a discipline, is the inventor of many guidelines and models, it appears to be a slow runner on practical implications of interface usability. This usability can influence end users’ attitude and behavior to use IT. The purpose of this paper was to examine the interface usability of a popular Enterprise Resource Planning (ERP software system, SAP, and to identify related issues and implications to the Technology Acceptance Model (TAM. A survey was conducted of 112 SAP ERP users from an organization in the heavy metal industry in Bangladesh. The partial least squares technique was used to analyze the survey data. The survey findings empirically confirmed that interface usability has a significant impact on users’ perceptions of usefulness and ease of use which ultimately affects attitudes and intention to use the ERP software. The research model extends the TAM by incorporating three criteria of interface usability. It is the first known study to investigate usability criteria as an extension of TAM.
Hirt, Martin; Nielsen, Jesper Buus; Przydatek, Bartosz
We present an efficient protocol for secure multi-party computation in the asynchronous model with optimal resilience. For n parties, up to t < n/3 of them being corrupted, and security parameter κ, a circuit with c gates can be securely computed with communication complexity O(cn^2k) bits, which...... circuit randomization due to Beaver (Crypto’91), and an abstraction of certificates, which can be of independent interest....
Lim, Harry B T; Karageorghis, Costas I; Romer, Lee M; Bishop, Daniel T
Synchronizing movement to a musical beat may reduce the metabolic cost of exercise, but findings to date have been equivocal. Our aim was to examine the degree to which the synchronous application of music moderates the metabolic demands of a cycle ergometer task. Twenty-three recreationally active men made two laboratory visits. During the first visit, participants completed a maximal incremental ramp test on a cycle ergometer. At the second visit, they completed four randomized 6-min cycling bouts at 90% of ventilatory threshold (control, metronome, synchronous music, and asynchronous music). Main outcome variables were oxygen uptake, HR, ratings of dyspnea and limb discomfort, affective valence, and arousal. No significant differences were evident for oxygen uptake. HR was lower under the metronome condition (122 ± 15 bpm) compared to asynchronous music (124 ± 17 bpm) and control (125 ± 16 bpm). Limb discomfort was lower while listening to the metronome (2.5 ± 1.2) and synchronous music (2.3 ± 1.1) compared to control (3.0 ± 1.5). Both music conditions, synchronous (1.9 ± 1.2) and asynchronous (2.1 ± 1.3), elicited more positive affective valence compared to metronome (1.2 ± 1.4) and control (1.2 ± 1.2), while arousal was higher with synchronous music (3.4 ± 0.9) compared to metronome (2.8 ± 1.0) and control (2.8 ± 0.9). Synchronizing movement to a rhythmic stimulus does not reduce metabolic cost but may lower limb discomfort. Moreover, synchronous music has a stronger effect on limb discomfort and arousal when compared to asynchronous music.
In the paper, there is analyzed the signal quality assessment method based on delay tap asynchronous sampling, both for binary and multilevel PAM signals. The obtained multilevel phase diagrams are far more complicated than binary ones. The phase diagrams are affected by the signal distortions but it is difficult to relate reliably the phase diagram form to the distortion type and its influence on the signal quality.
AbdulJabbar, Mustafa; Yokota, Rio; Keyes, David
Fast multipole methods (FMM) on distributed mem- ory have traditionally used a bulk-synchronous model of com- municating the local essential tree (LET) and overlapping it with computation of the local data. This could be perceived as an extreme case of data aggregation, where the whole LET is communicated at once. Charm++ allows a much finer control over the granularity of communication, and has a asynchronous execution model that fits well with the structure of our FMM code. Unlike previous ...
Full Text Available Abstract Background Traditionally synchronous access strategies require users to comply with one or more time constraints in order to communicate intent with a binary human-machine interface (e.g., mechanical, gestural or neural switches. Asynchronous access methods are preferable, but have not been used with binary interfaces in the control of devices that require more than two commands to be successfully operated. Methods We present the mathematical development and evaluation of a novel asynchronous access method that may be used to translate sporadic activations of binary interfaces into distinct outcomes for the control of devices requiring an arbitrary number of commands to be controlled. With this method, users are required to activate their interfaces only when the device under control behaves erroneously. Then, a recursive algorithm, incorporating contextual assumptions relevant to all possible outcomes, is used to obtain an informed estimate of user intention. We evaluate this method by simulating a control task requiring a series of target commands to be tracked by a model user. Results When compared to a random selection, the proposed asynchronous access method offers a significant reduction in the number of interface activations required from the user. Conclusion This novel access method offers a variety of advantages over traditionally synchronous access strategies and may be adapted to a wide variety of contexts, with primary relevance to applications involving direct object manipulation.
Marisa, T; Niederhauser, T; Haeberlin, A; Wildhaber, R A; Vogel, R; Goette, J; Jacomet, M
A new pseudo asynchronous level crossing analogue-to-digital converter (adc) architecture targeted for low-power, implantable, long-term biomedical sensing applications is presented. In contrast to most of the existing asynchronous level crossing adc designs, the proposed design has no digital-to-analogue converter (dac) and no continuous time comparators. Instead, the proposed architecture uses an analogue memory cell and dynamic comparators. The architecture retains the signal activity dependent sampling operation by generating events only when the input signal is changing. The architecture offers the advantages of smaller chip area, energy saving and fewer analogue system components. Beside lower energy consumption the use of dynamic comparators results in a more robust performance in noise conditions. Moreover, dynamic comparators make interfacing the asynchronous level crossing system to synchronous processing blocks simpler. The proposed adc was implemented in [Formula: see text] complementary metal-oxide-semiconductor (cmos) technology, the hardware occupies a chip area of 0.0372 mm 2 and operates from a supply voltage of [Formula: see text] to [Formula: see text]. The adc's power consumption is as low as 0.6 μW with signal bandwidth from [Formula: see text] to [Formula: see text] and achieves an equivalent number of bits (enob) of up to 8 bits.
Ab Aziz, Nor Azlina; Mubin, Marizan; Mohamad, Mohd Saberi; Ab Aziz, Kamarulzaman
In the original particle swarm optimisation (PSO) algorithm, the particles' velocities and positions are updated after the whole swarm performance is evaluated. This algorithm is also known as synchronous PSO (S-PSO). The strength of this update method is in the exploitation of the information. Asynchronous update PSO (A-PSO) has been proposed as an alternative to S-PSO. A particle in A-PSO updates its velocity and position as soon as its own performance has been evaluated. Hence, particles are updated using partial information, leading to stronger exploration. In this paper, we attempt to improve PSO by merging both update methods to utilise the strengths of both methods. The proposed synchronous-asynchronous PSO (SA-PSO) algorithm divides the particles into smaller groups. The best member of a group and the swarm's best are chosen to lead the search. Members within a group are updated synchronously, while the groups themselves are asynchronously updated. Five well-known unimodal functions, four multimodal functions, and a real world optimisation problem are used to study the performance of SA-PSO, which is compared with the performances of S-PSO and A-PSO. The results are statistically analysed and show that the proposed SA-PSO has performed consistently well. PMID:25121109
Full Text Available Mobile group consumption refers to consumption by a group of people, such as a couple, a family, colleagues and friends, based on mobile communications. It differs from consumption only involving individuals, because of the complex relations among group members. Existing data collection systems for mobile group consumption are centralized, which has the disadvantages of being a performance bottleneck, having single-point failure and increasing business and security risks. Moreover, these data collection systems are based on a synchronized clock, which is often unrealistic because of hardware constraints, privacy concerns or synchronization cost. In this paper, we propose the first asynchronous distributed approach to collecting data generated by mobile group consumption. We formally built a system model thereof based on asynchronous distributed communication. We then designed a simulation system for the model for which we propose a three-layer solution framework. After that, we describe how to detect the causality relation of two/three gathering events that happened in the system based on the collected data. Various definitions of causality relations based on asynchronous distributed communication are supported. Extensive simulation results show that the proposed approach is effective for data collection relating to mobile group consumption.
Zhu, Weiping; Chen, Weiran; Hu, Zhejie; Li, Zuoyou; Liang, Yue; Chen, Jiaojiao
Mobile group consumption refers to consumption by a group of people, such as a couple, a family, colleagues and friends, based on mobile communications. It differs from consumption only involving individuals, because of the complex relations among group members. Existing data collection systems for mobile group consumption are centralized, which has the disadvantages of being a performance bottleneck, having single-point failure and increasing business and security risks. Moreover, these data collection systems are based on a synchronized clock, which is often unrealistic because of hardware constraints, privacy concerns or synchronization cost. In this paper, we propose the first asynchronous distributed approach to collecting data generated by mobile group consumption. We formally built a system model thereof based on asynchronous distributed communication. We then designed a simulation system for the model for which we propose a three-layer solution framework. After that, we describe how to detect the causality relation of two/three gathering events that happened in the system based on the collected data. Various definitions of causality relations based on asynchronous distributed communication are supported. Extensive simulation results show that the proposed approach is effective for data collection relating to mobile group consumption.
The paper proposes a contingent, learner-centred usability evaluation method and a prototype tool of such systems. This is a new usability evaluation method for web-based learning systems using a set of empirically-supported usability factors and can be done effectively with limited resources. During the evaluation process, the method allows for…
Bunz, Ulla K.
This paper discusses Web site usability issues. Specifically, it assumes that the usability of a Web site depends more on the perception of the user than on the objectively assessable usability criteria of the Web site. Two pilot studies, based on theoretical notions of uses and gratifications theory and similar theories, are presented. In the…
Bruun , Anders
Part 1: Long and Short Papers; International audience; Lack of usability specialists, high resource requirements and developer mindsets are three considerable barriers for introducing usability engineering into software companies. This Ph.D. project explores the effect of letting software developers and end users apply usability engineering methods instead of a specialist, a solution which may reduce the barriers.
Can we use the methods of Web usability testing to learn about library instruction? This article is among the first in the field trying to establish a link between usability and instruction. The author discusses useful insights that Web usability can bring to our pedagogy as well as to the efficiency of library instruction. The result of a Web…
Full Text Available A Study about libraries' web sites evaluation, that is the Usability, the study talking about methods of usability testing and define it, and its important in web sites evaluation, then details the methods of usability: questionnaire, core groups, testing experimental model, cards arrangement, and composed evaluation.
This document presented a detailed mathematical explanation and validation of the steps leading to the development of an asynchronous squirrel-cage machine. The MatLab/Simulink software was used to model a wind turbine at variable high speeds. The asynchronous squirrel-cage machine is an electromechanical system coupled to a magnetic circuit. The resulting electromagnetic circuit can be represented as a set of resistances, leakage inductances and mutual inductances. Different models were used for a comparison study, including the Munteanu, Boldea, Wind Turbine Blockset, and SimPowerSystem. MatLab/Simulink modeling results were in good agreement with the results from other comparable models. Simulation results were in good agreement with analytical calculations. 6 refs, 2 tabs, 9 figs.
B. I. Firago
Full Text Available The paper considers the issue of one of the widespread types of vector control realization for the asynchronous motors with a short-circuited rotor. Of all more than 20 vector control types known presently, the following are applied most frequently: direct vector control with velocity pickup (VP, direct vector control without VP, indirect vector control with VP and indirect vector control without VP. Despite the fact that the asynchronous-motor indirect vector control without VP is the easiest and most spread, the absence of VP does not allow controlling the motor electromagnetic torque at zero velocity. This is the reason why for electric motor drives of such requirements they utilize the vector control with a velocity transducer. The systems of widest dissemination became the direct and indirect vector control systems with X-axis alignment of the synchronously rotating x–y-coordinate frame along the rotor flux-linkage vector inasmuch as this provides the simplest correlations for controlling variables. Although these two types of vector control are well presented in literature, a number of issues concerning their realization and practical application require further elaboration. These include: the block schemes adequate representation as consisted with the modern realization of vector control and clarification of the analytical expressions for evaluating the regulator parameters.The authors present a technique for evaluating the dynamics of an asynchronous electric motor drive with direct vector control and x-axis alignment along the vector of rotor flux linkage. The article offers a generalized structure of this vector control type with detailed description of its principal blocks: controlling system, frequency converter, and the asynchronous motor.The paper presents a direct vector control simulating model developed in the MatLab environment on the grounds of this structure. The authors illustrate the described technique with the results
Alexander, Keith; Blakstad, Siri; Hansen, Geir
The paper argues for the development of usability concepts, methodologies and tools, in considering the effects of the built environment from a user, organisational and community perspective, in order to have a positive influence on social outcomes. Since it was formed over ten years ago, the CIB W......111 on Usability has been exploring concepts, methods and tools, developed in the evaluation of all kinds of consumer products, applied to the built environment. In the most recent phase of this work, conducted over the past three years, an international network of partners has collaborated to focus...... properties of a workplace, they could better manage and design the facilities for improved social outcomes. Interpretation and analysis of the built environment (and support services) based on how it is socially constructed will enable integration of organisational use and the facilities provided to arrive...
Hussain, Azham; Mkpojiogu, Emmanuel O. C.; Jamaludin, Nur Hafiza; Moh, Somia T. L.
This paper reports on a usability evaluation of Lazada mobile application, an online shopping app for mobile devices. The evaluation was conducted using 12 users of ages 18 to 24. Seven (7) were expert users and the other 5 were novice users. The study objectives were to evaluate the perceived effectiveness, efficiency and satisfaction of the mobile application. The result provides a positive feedback and shows that the mobile shopping app is effective, efficient, and satisfying as perceived by the study participants. However, there are some observed usability issues with the main menu and the payment method that necessitates improvements to increase the application's effectiveness, efficiency and satisfaction. The suggested improvements include: 1) the main menu should be capitalized and place on the left side of mobile app and 2) payment method tutorial should be included as a hyperlink in the payment method page. This observation will be helpful to the owners of the application in future version development of the app.
Both the United States and Russia are retaining as strategic reserves more plutonium and HEU for potential reuse as weapons, than is legitimately needed. Both have engaged in discussions and have programs in various stages of development to dispose of excess plutonium and HEU. These fissile material disposition programs will take decades to complete. In the interim there will be, as there is now, hundreds of tons of separated weapon-usable fissile material stored in tens of thousands of transportable canisters, each containing from a few to several tons of kgs of weapon-usable fissile material. This material must be secured against theft and unauthorized use. To have high confidence that the material is secure, one must establish criteria against which the adequacy of the protective systems can be judged. For example, one finds such criteria in US Nuclear Regulatory Commission (USNRC) regulations for the protection of special nuclear materials
Full Text Available One strategy used to assure that an interface meets user requirements is to conduct usability testing. When conducting such testing one of the unknowns is sample size. Since extensive testing is costly, minimizing the number of participants can contribute greatly to successful resource management of a project. Even though a significant number of models have been proposed to estimate sample size in usability testing, there is still not consensus on the optimal size. Several studies claim that 3 to 5 users suffice to uncover 80% of problems in a software interface. However, many other studies challenge this assertion. This study analyzed data collected from the user testing of a web application to verify the rule of thumb, commonly known as the “magic number 5”. The outcomes of the analysis showed that the 5-user rule significantly underestimates the required sample size to achieve reasonable levels of problem detection.
Buxton, Eric C
To evaluate and compare pharmacists' satisfaction with the content and learning environment of a continuing education program series offered as either synchronous or asynchronous webinars. An 8-lecture series of online presentations on the topic of new drug therapies was offered to pharmacists in synchronous and asynchronous webinar formats. Participants completed a 50-question online survey at the end of the program series to evaluate their perceptions of the distance learning experience. Eighty-two participants completed the survey instrument (41 participants from the live webinar series and 41 participants from the asynchronous webinar series.) Responses indicated that while both groups were satisfied with the program content, the asynchronous group showed greater satisfaction with many aspects of the learning environment. The synchronous and asynchronous webinar participants responded positively regarding the quality of the programming and the method of delivery, but asynchronous participants rated their experience more positively overall.
Garcés, Ma. I.; Torralba, B.
The Research and Development (R&D) project on “Theoretical and Methodological Approaches to Integrated System Validation of Control Rooms, 2014-2015”, in which the research activities described in this report are framed, has two main objectives: to develop the items for an usability methodology conceived as a part of the measurement framework for performance-based control room evaluation that the OECD Halden Reactor Project will test in the experiments planned for 2015; and the statistical analysis of the data generated in the experimental activities of the Halden Man-Machine Laboratory (HAMMLAB) facility, with previous usability questionnaires, in 2010 and 2011. In this report, the procedure designed to meet the first goal of the project is described, in particular, the process followed to identify the items related to operating procedures, both computer and paper-based, one of the elements to be included in the usability questionnaire. Three phases are performed, in the first one, the approaches developed by the United States Nuclear Regulatory Commission, NRC, are reviewed, the models used by the nuclear industry and their technical support organizations, mainly, the Electric Power Research Institute, EPRI, are analyzed, and scientist advances are also explored. In the remaining stages, general and specific guidelines for computerized and paper-based procedures are compared and criteria for the preliminary selection of the items that should be incorporated into the usability questionnaire are defined. This proposal will be reviewed and adapted by the Halden Reactor Project to the design of the specific experiments performed in HAMLAB.
Kushniruk, Andre W; Borycki, Elizabeth M; Kannry, Joseph
The need for improved usability in healthcare IT has been widely recognized. In addition, methods from usability engineering, including usability testing and usability inspection have received greater attention. Many vendors of healthcare software are now employing usability testing methods in the design and development of their products. However, despite this, the usability of healthcare IT is still considered to be problematic and many healthcare organizations that have purchased systems that have been tested at vendor testing sites are still reporting a range of usability and safety issues. In this paper we explore the distinction between commercial usability testing (conducted at centralized vendor usability laboratories and limited beta test sites) and usability testing that is carried out locally within healthcare organizations that have purchased vendor systems and products (i.e. public "in-situ" usability testing). In this paper it will be argued that both types of testing (i.e. commercial vendor-based testing) and in-situ testing are needed to ensure system usability and safety.
Kjeldskov, Jesper; Skov, Mikael B.; Stage, Jan
We report from a longitudinal laboratory-based usability evaluation of a health care information system. The purpose of the study was to inquire into the nature of usability problems experienced by novice and expert users, and to see to what extend usability problems of a health care information...... system may or may not disappear over time, as the nurses get more familiar with it-if time heals poor design? As our method for studying this, we conducted a longitudinal study with two key studies. A usability evaluation was conducted with novice users when an electronic patient record system was being......, we discuss implications for evaluating usability in health care....
Bornoe, Nis; Stage, Jan
The essence of usability evaluations is to produce feedback that supports the downstream utility so the interaction design can be improved and problems can be fixed. In practice, software development organizations experience several obstacles for conducting usability engineering. One suggested...... approach is to train and involve developers in all phases of usability activities from evaluations, to problem reporting, and making redesign proposals. Only limited work has previously investigated the impact of actively involving developers in usability engineering. In this paper, we present two small......, and problem fixing. At the organizational level, we found that the attitude towards and understanding of the role of usability engineering improved....
Sousa, Vanessa E C; Dunn Lopez, Karen
The use of e-health can lead to several positive outcomes. However, the potential for e-health to improve healthcare is partially dependent on its ease of use. In order to determine the usability for any technology, rigorously developed and appropriate measures must be chosen. To identify psychometrically tested questionnaires that measure usability of e-health tools, and to appraise their generalizability, attributes coverage, and quality. We conducted a systematic review of studies that measured usability of e-health tools using four databases (Scopus, PubMed, CINAHL, and HAPI). Non-primary research, studies that did not report measures, studies with children or people with cognitive limitations, and studies about assistive devices or medical equipment were systematically excluded. Two authors independently extracted information including: questionnaire name, number of questions, scoring method, item generation, and psychometrics using a data extraction tool with pre-established categories and a quality appraisal scoring table. Using a broad search strategy, 5,558 potentially relevant papers were identified. After removing duplicates and applying exclusion criteria, 35 articles remained that used 15 unique questionnaires. From the 15 questionnaires, only 5 were general enough to be used across studies. Usability attributes covered by the questionnaires were: learnability (15), efficiency (12), and satisfaction (11). Memorability (1) was the least covered attribute. Quality appraisal showed that face/content (14) and construct (7) validity were the most frequent types of validity assessed. All questionnaires reported reliability measurement. Some questionnaires scored low in the quality appraisal for the following reasons: limited validity testing (7), small sample size (3), no reporting of user centeredness (9) or feasibility estimates of time, effort, and expense (7). Existing questionnaires provide a foundation for research on e-health usability. However
Maisonneuve, Hubert; Chambe, Juliette; Lorenzo, Mathieu; Pelaccia, Thierry
Blended learning environments - involving both face-to-face and remote interactions - make it easier to adapt learning programs to constraints such as residents' location and low teacher-student ratio. Social networking sites (SNS) such as Facebook®, while not originally intended to be used as learning environments, may be adapted for the distance-learning part of training programs. The purpose of our study was to explore the use of SNS for asynchronous distance learning in a blended learning environment as well as its influence on learners' face-to-face interactions. We conducted a qualitative study and carried out semi-structured interviews. We performed purposeful sampling for maximal variation to include eight general practice residents in 2(nd) and 3(rd) year training. A thematic analysis was performed. The social integration of SNS facilitates the engagement of users in their learning tasks. This may also stimulate students' interactions and group cohesion when members meet up in person. Most of the general practice residents who work in the blended learning environment we studied had a positive appraisal on their use of SNS. In particular, we report a positive impact on their engagement in learning and their participation in discussions during face-to-face instruction. Further studies are needed in order to evaluate the effectiveness of SNS in blended learning environments and the appropriation of SNS by teachers.
Weber, Griffin; Vinterbo, Staal; Ohno-Machado, Lucila
Various unsupervised and supervised learning methods including support vector machines, classification trees, linear discriminant analysis and nearest neighbor classifiers have been used to classify high-throughput gene expression data. Simpler and more widely accepted statistical tools have not yet been used for this purpose, hence proper comparisons between classification methods have not been conducted. We developed free software that implements logistic regression with stepwise variable selection as a quick and simple method for initial exploration of important genetic markers in disease classification. To implement the algorithm and allow our collaborators in remote locations to evaluate and compare its results against those of other methods, we developed a user-friendly asynchronous web-based application with a minimal amount of programming using free, downloadable software tools. With this program, we show that classification using logistic regression can perform as well as other more sophisticated algorithms, and it has the advantages of being easy to interpret and reproduce. By making the tool freely and easily available, we hope to promote the comparison of classification methods. In addition, we believe our web application can be used as a model for other bioinformatics laboratories that need to develop web-based analysis tools in a short amount of time and on a limited budget.
Wozney, Lori; Baxter, Pamela; Newton, Amanda S
Use of the Internet to deliver cognitive behavioural therapy, a frontline treatment for anxiety disorders, is emerging as an option to increase access to treatment among adolescents with anxiety disorders. This study examined the usability of the Internet-based component of Breathe, a CBT program designed for adolescents with mild to moderate anxiety and impairments. A mixed-method usability testing design with semi-structured interviews, task completion, and survey by trained usability moderators was undertaken with two interactive cycles to determine the usability (ease of use, efficiency, errors, and user satisfaction) of the user interface and content areas of the program. Purposeful sampling was used to recruit mental health clinicians with expertise in treating adolescent anxiety disorders and young people aged 15 to 24 years involved. Testing involved using Web-conferencing software that allowed remote participation through personal computers. Two testing cycles involved participants completing structured 'think aloud' and 'cognitive walkthrough' tasks within the program. At the end of each cycle participants completed a 15-item global usability evaluation survey and were asked a series of open-ended questions. Descriptive and simple content analyses were used to identify and score usability issues for frequency and severity. Five clinicians and four young people (all user performance indicators (i.e., learnability, efficiency and number of errors) and user satisfaction. Participants were able to complete all critical tasks with minimal errors. Errors and issues identified during testing were predominantly around enhancements to the visual design and navigational support. Opinions across usability elements did not differ between young people and clinician participants. A multi-method remote usability approach provided the opportunity to improve the technical interface, therapeutic messaging and user experience of an Internet-based treatment program for
Antonovičs, Uldis; Bražis, Viesturs; Greivulis, Jānis
The research object is squirrel-cage asynchronous motor connected to single-phase sinusoidal. There are shown, that by connecting to the stator windings a certain sequence of half-period positive and negative voltage, a motor rotor is rotated, but three times slower than in the three-phase mode. Changing the connecting sequence of positive and negative half-period voltage to stator windings, motor can work in various oscillating modes. It is tested experimentally. The mechanical transient processes had been researched in rotation and oscillating modes.
Wolff, Sebastian; Bucher, Christian
Asynchronous variational integration (AVI) is a tool which improves the numerical efficiency of explicit time stepping schemes when applied to finite element meshes with local spatial refinement. This is achieved by associating an individual time step length to each spatial domain. Furthermore, long-term stability is ensured by its variational structure. This article presents AVI in the context of finite elements based on a weakened weak form (W2) Liu (2009) , exemplified by continuous assumed gradient elements Wolff and Bucher (2011) . The article presents the main ideas of the modified AVI, gives implementation notes and a recipe for estimating the critical time step.
Gabriela Trindade Perry
Full Text Available In this paper, we present the results of a usability evaluation for Xenubi, a cell phone game about the periodic table. We describe and discuss the issues that we faced during the evaluation, which took place in a state high school. These issues are related to conflicts between the data that were gathered through video recordings and through a questionnaire. We also point to the poor performance of the game mechanics during the evaluation. This result was unexpected because the game had an excellent performance in the pilot test. Possible causes for these differences are discussed.
Calado, Alexana Vilar Soares; Soares, Marcelo Márcio
This paper refers to the comparative study of the equipment used for cooking in commercial of kitchens restaurants that use the system of traditional cooking and those ones which use the system called smart cooking (combination oven). The study investigates the usability issues concerning to the two systems, analyzing comparatively the aspects related to anthropometry, dimensional variables, the use of the product and also the product safety, as well as issues of information related to operation of the new concepts of cooking in intelligent systems.
Diebner, Hans H.; Grond, Florian
We discuss the synchronization features of a previously introduced adaptive system for dynamics recognition in more detail. We investigate the usability of synchronization for modeling and parameter estimations. It is pointed out inhowfar the adaptive system based on synchronization can become a powerful tool in modeling. The adaptive system can store modules of pre-adapted dynamics and is potentially capable of undergoing self-modification. We compare the stored modules with pre-knowledge that a modeler puts into his or her models. In this sense the adaptive system functions like an expert system
Kampik, Timotheus; Larsen, Frank; Bellika, Johan Gustav
The objective of the study was to identify experiences and attitudes of German and Norwegian general practitioners (GPs) towards Internet-based remote consultation solutions supporting communication between GPs and patients in the context of the German and Norwegian healthcare systems. Interviews with four German and five Norwegian GPs were conducted. The results were qualitatively analyzed. All interviewed GPs stated they would like to make use of Internet-based remote consultations in the future. Current experiences with remote consultations are existent to a limited degree. No GP reported to use a comprehensive remote consultation solution. The main features GPs would like to see in a remote consultation solution include asynchronous exchange of text messages, video conferencing with text chat, scheduling of remote consultation appointments, secure login and data transfer and the integration of the remote consultation solution into the GP's EHR system.
Electrotechnics - AC motors. Asynchronous and brush-less motors - Lecture and exercises with solutions; Electrotechnique - Moteurs a courant alternatif. Moteurs asynchrones et brushless - Cours et problemes resolus
This book proposes a presentation of AC electric motors essentially based on physics and technology. Its originality consists in avoiding to use mathematical formulations (like Park's transformation). The modeling retained, which only uses magnetic momentum, magnetic fields and reluctance concepts, leads simply and naturally to the vectorial control principle. The book develops some lecture elements which includes some topics rarely considered like the dimensioning of an asynchronous motor or of a single-phase brush-less motor. Experimental results illustrate the physical phenomena described and many original problems are resolved and commented at the end of each chapter. Content: signals and systems in electrotechnics, torque and rotating magnetic fields generation, asynchronous machine in permanent regime, speed variation of the asynchronous motor, special asynchronous motors, synchronous machine in permanent regime, brush-less motor, note about step motors, note about inverters, index. (J.S.)
Nielsen, Sune Fallgaard; Sparsø, Jens; Madsen, Jan
This paper presents a method for behavioral synthesis of asynchronous circuits. Our approach aims at providing a synthesis flow which is very similar to what is found in existing synchronous design tools. We adapt the synchronous behavioral synthesis abstraction into the asynchronous handshake...
Tolman, Elizabeth; Asbury, Bryan
Asynchronous discussions are a useful instructional resource in the online communication course. In discussion groups students have the opportunity to actively participate and interact with students and the instructor. Asynchronous communication allows for flexibility because "participants can interact with significant amounts of time between…
Christensen, Kåre Tais; Jensen, P.; Korger, P.
This paper presents the design of an asynchronous version of the TR4101 embedded microprocessor core developed by LSI Logic Inc. The asynchronous processor, called ARISC, was designed using the same CAD tools and the same standard cell library that was used to implement the TR4101. The paper repo...
Brinkman, W.P.; Haakma, R.; Bouwhuis, D.G.; Jacob, R.J.K.; Limbourg, Q; Vanderdonckt, J.
Component-based Software Engineering (CBSE) is concerned with the development of systems from reusable parts (components), and the development and maintenance of these parts. This study addresses the issue of usability testing in a CBSE environment, and specifically automatically measuring the
Full Text Available This paper proposes a space-time block coding (STBC transmission scheme for asynchronous cooperative systems. By combination of rotated complex constellations and Hadamard transform, these constructed codes are capable of achieving full cooperative diversity with the analysis of the pairwise error probability (PEP. Due to the asynchronous characteristic of cooperative systems, orthogonal frequency division multiplexing (OFDM technique with cyclic prefix (CP is adopted for combating timing delays from relay nodes. The total transmit power across the entire network is fixed and appropriate power allocation can be implemented to optimize the network performance. The relay nodes do not require decoding and demodulation operation, resulting in a low complexity. Besides, there is no delay for forwarding the OFDM symbols to the destination node. At the destination node the received signals have the corresponding STBC structure on each subcarrier. In order to reduce the decoding complexity, the sphere decoder is implemented for fast data decoding. Bit error rate (BER performance demonstrates the effectiveness of the proposed scheme.
Full Text Available Cognitive radio networks (CRNs are considered an attractive technology to mitigate inefficiency in the usage of licensed spectrum. CRNs allow the secondary users (SUs to access the unused licensed spectrum and use a blind rendezvous process to establish communication links between SUs. In particular, quorum-based channel-hopping (CH schemes have been studied recently to provide guaranteed blind rendezvous in decentralized CRNs without using global time synchronization. However, these schemes remain vulnerable to jamming attacks. In this paper, we first analyze the limitations of quorum-based rendezvous schemes called asynchronous channel hopping (ACH. Then, we introduce a novel sequence sensing jamming attack (SSJA model in which a sophisticated jammer can dramatically reduce the rendezvous success rates of ACH schemes. In addition, we propose a fast and robust asynchronous rendezvous scheme (FRARS that can significantly enhance robustness under jamming attacks. Our numerical results demonstrate that the performance of the proposed scheme vastly outperforms the ACH scheme when there are security concerns about a sequence sensing jammer.
Jacobson, Seth A.; Scheeres, Daniel J.; McMahon, Jay
We propose and analyze a new mechanism for the formation of the wide asynchronous binary population. These binary asteroids have wide semimajor axes relative to most near-Earth and main belt asteroid systems. Confirmed members have rapidly rotating primaries and satellites that are not tidally locked. Previously suggested formation mechanisms from impact ejecta, from planetary flybys, and directly from rotational fission events cannot satisfy all of the observations. The newly hypothesized mechanism works as follows: (1) these systems are formed from rotational fission, (2) their satellites are tidally locked, (3) their orbits are expanded by the binary Yarkovsky-O'Keefe-Radzievskii-Paddack (BYORP) effect, (4) their satellites desynchronize as a result of the adiabatic invariance between the libration of the secondary and the mutual orbit, and (5) the secondary avoids resynchronization because of the YORP effect. This seemingly complex chain of events is a natural pathway for binaries with satellites that have particular shapes, which define the BYORP effect torque that acts on the system. After detailing the theory, we analyze each of the wide asynchronous binary members and candidates to assess their most likely formation mechanism. Finally, we suggest possible future observations to check and constrain our hypothesis.
Joel R. Noche
Full Text Available An asynchronous floating-point arithmetic unit is designed and tested at the transistor level usingCadence software. It uses CMOS (complementary metal oxide semiconductor and DCVS (differentialcascode voltage switch logic in a 0.35 µm process using a 3.3 V supply voltage, with dual-rail data andsingle-rail control signals using four-phase handshaking.Using 17,085 transistors, the unit handles single-precision (32-bit addition/subtraction, multiplication,division, and remainder using the IEEE 754-1985 Standard for Binary Floating-Point Arithmetic, withrounding and other operations to be handled by separate hardware or software. Division and remainderare done using a restoring subtractive algorithm; multiplication uses an additive algorithm. Exceptionsare noted by flags (and not trap handlers and the output is in single-precision.Previous work on asynchronous floating-point arithmetic units have mostly focused on single operationssuch as division. This is the first work to the authors' knowledge that can perform floating-point addition,multiplication, division, and remainder using a common datapath.
This paper introduces the first asynchronous, task-based implementation of the polar decomposition on manycore architectures. Based on a new formulation of the iterative QR dynamically-weighted Halley algorithm (QDWH) for the calculation of the polar decomposition, the proposed implementation replaces the original and hostile LU factorization for the condition number estimator by the more adequate QR factorization to enable software portability across various architectures. Relying on fine-grained computations, the novel task-based implementation is also capable of taking advantage of the identity structure of the matrix involved during the QDWH iterations, which decreases the overall algorithmic complexity. Furthermore, the artifactual synchronization points have been severely weakened compared to previous implementations, unveiling look-ahead opportunities for better hardware occupancy. The overall QDWH-based polar decomposition can then be represented as a directed acyclic graph (DAG), where nodes represent computational tasks and edges define the inter-task data dependencies. The StarPU dynamic runtime system is employed to traverse the DAG, to track the various data dependencies and to asynchronously schedule the computational tasks on the underlying hardware resources, resulting in an out-of-order task scheduling. Benchmarking experiments show significant improvements against existing state-of-the-art high performance implementations (i.e., Intel MKL and Elemental) for the polar decomposition on latest shared-memory vendors\\' systems (i.e., Intel Haswell/Broadwell/Knights Landing, NVIDIA K80/P100 GPUs and IBM Power8), while maintaining high numerical accuracy.
In this study, we propose a two-stage recognition system for continuous analysis of electroencephalogram (EEG) signals. An independent component analysis (ICA) and correlation coefficient are used to automatically eliminate the electrooculography (EOG) artifacts. Based on the continuous wavelet transform (CWT) and Student's two-sample t-statistics, active segment selection then detects the location of active segment in the time-frequency domain. Next, multiresolution fractal feature vectors (MFFVs) are extracted with the proposed modified fractal dimension from wavelet data. Finally, the support vector machine (SVM) is adopted for the robust classification of MFFVs. The EEG signals are continuously analyzed in 1-s segments, and every 0.5 second moves forward to simulate asynchronous BCI works in the two-stage recognition architecture. The segment is first recognized as lifted or not in the first stage, and then is classified as left or right finger lifting at stage two if the segment is recognized as lifting in the first stage. Several statistical analyses are used to evaluate the performance of the proposed system. The results indicate that it is a promising system in the applications of asynchronous BCI work.
Full Text Available Bio-inspired asynchronous event-based vision sensors are currently introducing a paradigm shift in visual information processing. These new sensors rely on a stimulus-driven principle of light acquisition similar to biological retinas. They are event-driven and fully asynchronous, thereby reducing redundancy and encoding exact times of input signal changes, leading to a very precise temporal resolution. Approaches for higher-level computer vision often rely on the realiable detection of features in visual frames, but similar definitions of features for the novel dynamic and event-based visual input representation of silicon retinas have so far been lacking. This article addresses the problem of learning and recognizing features for event-based vision sensors, which capture properties of truly spatiotemporal volumes of sparse visual event information. A novel computational architecture for learning and encoding spatiotemporal features is introduced based on a set of predictive recurrent reservoir networks, competing via winner-take-all selection. Features are learned in an unsupervised manner from real-world input recorded with event-based vision sensors. It is shown that the networks in the architecture learn distinct and task-specific dynamic visual features, and can predict their trajectories over time.
Venter, Gerhard; Sobieszczanski-Sobieski, Jaroslaw
A parallel Particle Swarm Optimization (PSO) algorithm is presented. Particle swarm optimization is a fairly recent addition to the family of non-gradient based, probabilistic search algorithms that is based on a simplified social model and is closely tied to swarming theory. Although PSO algorithms present several attractive properties to the designer, they are plagued by high computational cost as measured by elapsed time. One approach to reduce the elapsed time is to make use of coarse-grained parallelization to evaluate the design points. Previous parallel PSO algorithms were mostly implemented in a synchronous manner, where all design points within a design iteration are evaluated before the next iteration is started. This approach leads to poor parallel speedup in cases where a heterogeneous parallel environment is used and/or where the analysis time depends on the design point being analyzed. This paper introduces an asynchronous parallel PSO algorithm that greatly improves the parallel e ciency. The asynchronous algorithm is benchmarked on a cluster assembled of Apple Macintosh G5 desktop computers, using the multi-disciplinary optimization of a typical transport aircraft wing as an example.
Jang, Bongkyun; Kim, Byungwoon; Kim, Jae-Hyun; Lee, Hak-Joo; Sumigawa, Takashi; Kitamura, Takayuki
Multilayer graphene consists of a stack of single-atomic-thick monolayer graphene sheets bound with π-π interactions and is a fascinating model material opening up a new field of fracture mechanics. In this study, fracture behavior of single-crystalline multilayer graphene was investigated using an in situ mode I fracture test under a scanning electron microscope, and abnormal crack propagation in multilayer graphene was identified for the first time. The fracture toughness of graphene was determined from the measured load-displacement curves and the realistic finite element modelling of specimen geometries. Nonlinear fracture behavior of the multilayer graphene is discussed based on nonlinear elastic fracture mechanics. In situ scanning electron microscope images obtained during the fracture test showed asynchronous crack propagation along independent paths, causing interlayer shear stress and slippages. We also found that energy dissipation by interlayer slippages between the graphene layers is the reason for the enhanced fracture toughness of multilayer graphene. The asynchronous cracking with independent paths is a unique cracking and toughening mechanism for single-crystalline multilayer graphene, which is not observed for the monolayer graphene. This could provide a useful insight for the design and development of graphene-based composite materials for structural applications.
Coon, Darryl D.; Perera, A. G. U.
Research is being carried out on hardware for a new approach to focal plane processing. The hardware involves silicon injection mode devices. These devices provide a natural basis for parallel asynchronous focal plane image preprocessing. The simplicity and novel properties of the devices would permit an independent analog processing channel to be dedicated to every pixel. A laminar architecture built from arrays of the devices would form a two-dimensional (2-D) array processor with a 2-D array of inputs located directly behind a focal plane detector array. A 2-D image data stream would propagate in neuron-like asynchronous pulse-coded form through the laminar processor. No multiplexing, digitization, or serial processing would occur in the preprocessing state. High performance is expected, based on pulse coding of input currents down to one picoampere with noise referred to input of about 10 femtoamperes. Linear pulse coding has been observed for input currents ranging up to seven orders of magnitude. Low power requirements suggest utility in space and in conjunction with very large arrays. Very low dark current and multispectral capability are possible because of hardware compatibility with the cryogenic environment of high performance detector arrays. The aforementioned hardware development effort is aimed at systems which would integrate image acquisition and image processing.
Sandor, Aniko; Holden, Kritina L.
The Usability project addresses the need for research in the area of metrics and methodologies used in hardware and software usability testing in order to define quantifiable and verifiable usability requirements. A usability test is a human-in-the-loop evaluation where a participant works through a realistic set of representative tasks using the hardware/software under investigation. The purpose of this research is to define metrics and methodologies for measuring and verifying usability in the aerospace domain in accordance with FY09 focus on errors, consistency, and mobility/maneuverability. Usability metrics must be predictive of success with the interfaces, must be easy to obtain and/or calculate, and must meet the intent of current Human Systems Integration Requirements (HSIR). Methodologies must work within the constraints of the aerospace domain, be cost and time efficient, and be able to be applied without extensive specialized training.
as relevant and strategic human–computer interaction (HCI) activities in the software development process, there are obstacles that limit the complete, effective and efficient integration of this kind of testing into the software development process. Two main obstacles are the cost of usability evaluations...... and the software developers' resistance to accepting users’ opinions regarding the lack of usability in their software systems. The ‘cost obstacle’ refers to the constraint of conducting usability evaluations in the software process due to the significant amount of resources required by this type of testing. Some......This thesis addresses the integration of usability evaluations into the software development process. The integration here is contextualized in terms of how to include usability evaluation as an activity in the software development lifecycle. Even though usability evaluations are considered...
Full Text Available In the engineering curriculum, remote labs are becoming a popular learning tool. The advantages of these laboratories and the different deployments have been analyzed many times, but in this paper we want to show the results of the students’ opinion about WebLab-Deusto as a learning tool. This work is focused on the subjects Programmable Logic (PL in the third year of Electronics Engineering and in Electronics Design (ED of the fifth year of the same degree. The paper presents the results of the surveys done by students since 2004. This survey consists of fifteen questions and its main objective is to measure the acceptance, usability and usefulness of the remote laboratory developed at University of Deusto from the students point of view.
Yunus, U.; Anindito; Tanuar, E.; Maryani
Indonesian tourism has been viewed as one of the source of foreign exchange, therefore visit Indonesia campaign through Wonderful Indonesia should be given attention. This research aims to test the usability of web http://www.indonesia.travel/en, at the end can give input to the Tourism Ministry of the Republic of Indonesia. The concept used based on usabilitygeek.com which mentions the three main categories for usability testing, i. e. explorative, assessment and comparative with the users are three classes of Communication Department students of Bina Nusantara University with a total of 120 students, however finally only 22 students were elected because of the criteria are the students should be like travelling and access to the tourism website more than 12 times. The methodology used is qualitative descriptive and experiments, with data collection techniques through observation and interviews after participants’ access to the web: Due to their one-on-one nature, interviews enable the observer to ask direct questions to the user and the participants posted their opinion in online discussion forum. The results mentioned that the elements web of Wonderful Indonesia has a high learning ability and memorability but less efficiency and satisfaction, as well as several times errors when used. In conclusion, to maximize about the visit of tourism to Indonesia, this web is only able to learn and impress the visitor, but do not give satisfaction to users.
Rocchio, L. E.; Davis, A. L.
Science has long served humankind. Breakthroughs in medicine have increased longevity and advances in technology have made modern-day conveniences possible. Yet, social benefits begotten by the environmental sciences, although critical for the survival of humanity, have not always been as widely recognized or used. To benefit today's rapidly growing population, the divides between environmental research, applied environmental science, and use of this information by decision makers must be bridged. Lessons about the translation from research to usable science can be learned from the four decades of Landsat history, and these lessons can serve as useful models for bridging the gaps between new technology, scientific research, and the use of that research and technology in real-world problem solving. In 1965, William Pecora, then-director of the U.S. Geological Survey, proposed the idea of a remote sensing satellite program to gather facts about natural resources of Earth. For the next seven years, an intense campaign showing the depth and diversity of satellite imagery applications was waged. This led to the 1972 launch of the first civilian land-observing satellite, Landsat 1. By 1975, successful application research based on Landsat 1 imagery prompted then-NASA Administrator Dr. James Fletcher to proclaim that if one space age development would save the world, it would be Landsat and its successor satellites. Thirty-four years of continual Landsat imaging and related-research has lead to the implementation of many socially beneficial applications, such as improved water management techniques, crop insurance fraud reduction, illicit crop inventories, natural disaster relief planning, continent-scale carbon estimates, and extensive cartographic advances. Despite these successes, the challenge of translating Landsat research into realized social benefits remains. Even in this geospatially-savvy era, the utility of Landsat largely escapes policymakers. Here, in an
Kasapaki, Evangelia; Sparsø, Jens; Sørensen, Rasmus Bo
In this paper we explore the design of an asynchronous router for a time-division-multiplexed (TDM) network-on-chip (NOC) that is being developed for a multi-processor platform for hard real-time systems. TDM inherently requires a common time reference, and existing TDM-based NOC designs are either....... This adds hardware complexity and increases area and power consumption. We propose to use asynchronous routers in order to achieve a simpler, more robust and globally-asynchronous NOC, and this represents an unexplored point in the design space. The paper presents a range of alternative router designs. All...... routers have been synthesized for a 65nm CMOS technology, and the paper reports post-layout figures for area, speed and energy and compares the asynchronous designs with an existing mesochronous clocked router. The results show that an asynchronous router is 2 times smaller, marginally slower...
Business-Intelligence-Systeme stehen im Spannungsfeld zwischen Usability und Sicherheit. Die Gefahren und Sicherheitsmaßnahmen für Informationssysteme werden ermittelt und ökonomisch in Bezug zur Gebrauchstauglichkeit gesetzt. Es entsteht ein Sicherheitsprofil für Business-Intelligence-Systeme. Business-Intelligence-Systems are in tension between Usability and IT-Security. Risks and safety measures of informationsystems are defined and set in (economic) regard to Usability. A security prof...
Hussain, Azham; Mkpojiogu, Emmanuel O. C.
Obviously, there are a number of literatures concerning the usability of mobile commerce (m-commerce) applications and related areas, but they do not adequately provide knowledge about usability techniques used in most of the empirical usability evaluation for m-commerce application. Therefore, this paper is aimed at producing the usability techniques frequently used in the aspect of usability evaluation for m-commerce applications. To achieve the stated objective, systematic literature review was employed. Sixty seven papers were downloaded in usability evaluation for m-commerce and related areas; twenty one most relevant studies were selected for review in order to extract the appropriate information. The results from the review shows that heuristic evaluation, formal test and think aloud methods are the most commonly used methods in m-commerce application in comparison to cognitive walkthrough and the informal test methods. Moreover, most of the studies applied control experiment (33.3% of the total studies); other studies that applied case study for usability evaluation are 14.28%. The results from this paper provide additional knowledge to the usability practitioners and research community for the current state and use of usability techniques in m-commerce application.
Tyllinen, Mari; Kaipio, Johanna; Lääveri, Tinja
Usability should be considered already by the procuring organizations when selecting future systems. In this paper, we present a framework for usability evaluation during electronic health record (EHR) system procurement. We describe the objectives of the evaluation, the procedure, selected usability attributes and the evaluation methods to measure them. We also present the emphasis usability had in the selection process. We do not elaborate on the details of the results, the application of methods or gathering of data. Instead we focus on the components of the framework to inform and give an example to other similar procurement projects.
The cultural diversity of users of technology challenges our methods for usability testing. This article suggests templates for cross-culturally and culturally specific usability testing, based on studies of usability testing in companies in Mumbai, Beijing, and Copenhagen. Study 1 was a cross...... tests. The result was the construction of templates for usability testing. The culturally specific templates were in Mumbai “user-centered evaluation,” Copenhagen “client-centered evaluation,” and Beijing “evaluator-centered evaluation.” The findings are compared with related research...
Bias, Randolph G; Bias, Randolph G
You just know that an improvement of the user interface will reap rewards, but how do you justify the expense and the labor and the time-guarantee a robust ROI!-ahead of time? How do you decide how much of an investment should be funded? And what is the best way to sell usability to others? In this completely revised and new edition, Randolph G. Bias (University of Texas at Austin, with 25 years' experience as a usability practitioner and manager) and Deborah J. Mayhew (internationally recognized usability consultant and author of two other seminal books including The Usability Enginee
Stephanie Bettina Linek
Full Text Available The usability of Web sites and online services is of rising importance. When creating a completely new Web site, qualitative data are adequate for identifying the most usability problems. However, changes of an existing Web site should be evaluated by a quantitative benchmarking process. The proposed paper describes the creation of a questionnaire that allows a quantitative usability benchmarking, i.e. a direct comparison of the different versions of a Web site and an orientation on general standards of usability. The questionnaire is also open for qualitative data. The methodology will be explained by the digital library services of the ZBW.
The purposes of this article are to describe usability testing and introduce designs and methods of usability testing research as it relates to upper-limb prosthetics. This article defines usability, describes usability research, discusses research approaches to and designs for usability testing, and highlights a variety of methodological considerations, including sampling, sample size requirements, and usability metrics. Usability testing is compared with other types of study designs used in prosthetic research.
Shi, Xuanhua; Luo, Xuan; Liang, Junling; Zhao, Peng; Di, Sheng; He, Bingsheng; Jin, Hai
GPUs have been increasingly used to accelerate graph processing for complicated computational problems regarding graph theory. Many parallel graph algorithms adopt the asynchronous computing model to accelerate the iterative convergence. Unfortunately, the consistent asynchronous computing requires locking or atomic operations, leading to significant penalties/overheads when implemented on GPUs. As such, coloring algorithm is adopted to separate the vertices with potential updating conflicts, guaranteeing the consistency/correctness of the parallel processing. Common coloring algorithms, however, may suffer from low parallelism because of a large number of colors generally required for processing a large-scale graph with billions of vertices. We propose a light-weight asynchronous processing framework called Frog with a preprocessing/hybrid coloring model. The fundamental idea is based on Pareto principle (or 80-20 rule) about coloring algorithms as we observed through masses of realworld graph coloring cases. We find that a majority of vertices (about 80%) are colored with only a few colors, such that they can be read and updated in a very high degree of parallelism without violating the sequential consistency. Accordingly, our solution separates the processing of the vertices based on the distribution of colors. In this work, we mainly answer three questions: (1) how to partition the vertices in a sparse graph with maximized parallelism, (2) how to process large-scale graphs that cannot fit into GPU memory, and (3) how to reduce the overhead of data transfers on PCIe while processing each partition. We conduct experiments on real-world data (Amazon, DBLP, YouTube, RoadNet-CA, WikiTalk and Twitter) to evaluate our approach and make comparisons with well-known non-preprocessed (such as Totem, Medusa, MapGraph and Gunrock) and preprocessed (Cusha) approaches, by testing four classical algorithms (BFS, PageRank, SSSP and CC). On all the tested applications and
Full Text Available Business Intelligence (BI applications provide business information to drive decision support. Usability is one of the factors determining the optimal use and eventual benefit derived from BI applications. The documented need for more BI usability research together with the practical necessity for BI evaluation guidelines in the mining industry provides the rationale for this study. The purpose of the study was to investigate the usability evaluation of BI applications in the context of a coal mining organization. The research is guided by the question: How can existing usability criteria be customized to evaluate the usability of BI applications. The research design included user observation, heuristic evaluation and a survey. Based on observations made during user support on a BI application used at a coal mining organization a log of usability issues was compiled. The usability issues extracted from this log was compared and contrasted with general usability criteria from literature to synthesize an initial set of BI usability evaluation criteria. These criteria were used as the basis for a heuristic evaluation of the BI application used at the coal mining organization. The same BI application was also evaluated using the Software Usability Measurement Inventory (SUMI standardized questionnaire. The results from the two evaluations were triangulated and then compared with the BI user issues again to contextualize the findings and synthesize a validated and refined set of criteria. The main contribution of the study is the usability evaluation criteria for BI applications presented as guidelines. These guidelines deviate from existing evaluation guidelines in the emphasis on information architecture, learnability and operability.
Full Text Available Online biodiversity portals and databases enabling access to large volumes of biological information represent a potentially extensive set of resources for a variety of user groups. However, in order for these resources to live up to their promise they need to be both useful and easy to use. We discuss a number of principles for designing systems for usability, examine how these have been applied to the development of online biodiversity resources and compare this with a portal project developed by the Astrophysics community. We highlight a lack of user involvement and formalised requirements analysis by biodiversity projects resulting in a poor understanding of both the users and their tasks. We suggest a change in the way large biodiversity portal projects are structured, that is by providing infrastructure and supporting user groups developing individual interfaces.
Veland, Oeystein; Kaarstad, Magnhild; Seim, Lars Aage; Foerdestroemmen, Nils T.
This document describes the result of a study on alarm systems conducted by IFE in Halden. The study was initiated by the Norwegian Petroleum Directorate. The objective was to identify and formulate a set of important properties for useful and usable alarm systems. The study is mainly based on review of the latest international recognised guidelines and standards on alarm systems available at the time of writing, with focus on realistic solutions from research and best practice from different industries. In addition, IFE experiences gathered through specification and design of alarm systems and experimental activities in HAMMLAB and bilateral projects, have been utilized where relevant. The document presents a total of 43 recommendations divided into a number of general recommendations and more detailed recommendations on alarm generation, structuring, prioritisation, presentation and handling. (Author)
Kavathatzopoulos, Iordanis; Kostrzewa, Agata; Laaksoharju, Mikael
The objectives of the tutorial are to provide knowledge of basic ethical, psychological and organizational theories that are relevant to consider ethical aspects during design and use of IT systems; knowledge and skills about handling and solving ethical problems in connection with design and use of IT-systems; and skills in using questionnaires, surveys, interviews and the like in connection with software development and IT-use. It contains lectures, workshop and exercises; use of special tools to identify and consider IT ethical issues during planning, construction, installation and use of IT systems; and group exercises where the participants train their ethical skills on IT ethical conflicts and problems. Intended participants are system developers, purchasers, usability experts, academics, HCI teachers.
José Manuel Ojel-Jaramillo
Full Text Available Demographic and sociological changes in the last 50 years have forced Western societies to create services to attend to elderly people in their homes, where they can live within familiar environments. Telecare involves a device plugged into a telephonic network that provides access to teams of professionals who can attend to the needs of the elderly in their homes. These devices have been designed according to the principles of universal design, but the great number of erroneous calls to telecare centers point to the necessity of enhancing the usability of the devices. One analysis of the cognitive functioning of elderly people showed that a possible cause of these errors could be the difficulty elderly people have when processing language. In our experiment, we tested the hypothesis that the numbers of errors could be reduced by using icons instead of words in the device interface. The results support this hypothesis.
Cross, E. V., III; Perera, J. S.; Hanson, A. M.; English, K.; Vu, L.; Amonette, W.
Each exercise device on the International Space Station (ISS) has a unique, customized software system interface with unique layouts / hierarchy, and operational principles that require significant crew training. Furthermore, the software programs are not adaptable and provide no real-time feedback or motivation to enhance the exercise experience and/or prevent injuries. Additionally, the graphical user interfaces (GUI) of these systems present information through multiple layers resulting in difficulty navigating to the desired screens and functions. These limitations of current exercise device GUI's lead to increased crew time spent on initiating, loading, performing exercises, logging data and exiting the system. To address these limitations a Next Generation One Portal (NextGen One Portal) Crew Countermeasure System (CMS) was developed, which utilizes the latest industry guidelines in GUI designs to provide an intuitive ease of use approach (i.e., 80% of the functionality gained within 5-10 minutes of initial use without/limited formal training required). This is accomplished by providing a consistent interface using common software to reduce crew training, increase efficiency & user satisfaction while also reducing development & maintenance costs. Results from the usability evaluations showed the NextGen One Portal UI having greater efficiency, learnability, memorability, usability and overall user experience than the current Advanced Resistive Exercise Device (ARED) UI used by astronauts on ISS. Specifically, the design of the One-Portal UI as an app interface similar to those found on the Apple and Google's App Store, assisted many of the participants in grasping the concepts of the interface with minimum training. Although the NextGen One-Portal UI was shown to be an overall better interface, observations by the test facilitators noted specific exercise tasks appeared to have a significant impact on the NextGen One-Portal UI efficiency. Future updates to
Raymond, D.M.; Hall, G.; Lewis, A.J.; Sharp, P.H.
A two-dimensional array of amplifier cells has been fabricated as a prototype readout system for a matching array of silicon diode detectors. Each cell contains a preamplifier, shaping amplifier, comparator and analogue signal storage in an area of 300 μmx320 μm using 3 μm CMOS technology. Full size chips will be bump bonded to pixel detector arrays. Low noise and asynchronous operation are novel design features. With noise levels of less than 250 rms electrons for input capacitances up to 600 fF, pixel detectors will be suitable for autoradiography, synchrotron X-ray and high energy particle detection applications. The design of the prototype chip is presented and future developments and prospects for applications are discussed. (orig.)
Mahmoud, Magdi S.; Memon, Azhar M.
While aperiodically triggered network control systems save a considerable amount of communication bandwidth, they also pose challenges such as coupling between control and event-condition design, optimisation of the available resources such as control, communication and computation power, and time-delays due to computation and communication network. With this motivation, the paper presents separate designs of control and event-triggering mechanism, thus simplifying the overall analysis, asynchronous linear quadratic Gaussian controller which tackles delays and aperiodic nature of transmissions, and a novel event mechanism which compares the cost of the aperiodic system against a reference periodic implementation. The proposed scheme is simulated on a linearised wind turbine model for pitch angle control and the results show significant improvement against the periodic counterpart.
Houghton, J D; Hays, G C
For many decades it has been accepted that marine turtle hatchlings from the same nest generally emerge from the sand together. However, for loggerhead turtles (Caretta caretta) nesting on the Greek Island of Kefalonia, a more asynchronous pattern of emergence has been documented. By placing temperature loggers at the top and bottom of nests laid on Kefalonia during 1998, we examined whether this asynchronous emergence was related to the thermal conditions within nests. Pronounced thermal variation existed not only between, but also within, individual nests. These within-nest temperature differences were related to the patterns of hatchling emergence, with hatchlings from nests displaying large thermal ranges emerging over a longer time-scale than those characterised by more uniform temperatures. In many egg-laying animals, parental care of the offspring may continue while the eggs are incubating and also after they have hatched. Consequently, the importance of the nest site for determining incubation conditions may be reduced since the parents themselves may alter the local environment. By contrast, in marine turtles, parental care ceases once the eggs have been laid and the nest site covered. The positioning of the nest site, in both space and time, may therefore have profound effects for marine turtles by affecting, for example, the survival of the eggs and hatchlings as well as their sex (Janzen and Paukstis 1991). During incubation, sea turtle embryos grow from a few cells at oviposition to a self-sufficient organism at hatching some 50-80 days later (Ackerman 1997). After hatching, the young turtles dig up through the sand and emerge typically en masse at the surface 1-7 nights later, with a number of stragglers following over the next few nights (Christens 1990). This contrasts with the frequently observed pattern of hatching asynchrony in birds. It has been suggested that the cause of mass emergence in turtles is that eggs within a clutch are fertilised
Mark P. Nelder
Full Text Available Succession patterns of adult blow flies (Diptera: Calliphoridae on decaying alligators were investigated in Mobile (Ala, USA during August 2002. The most abundant blow fly species visiting the carcasses were Chrysomya rufifacies (Macquart, Cochliomyia macellaria (Fabricus, Chrysomya megacephala (Fabricus, Phormia regina (Meigen, and Lucilia coeruleiviridis (Macquart. Lucilia coeruleiviridis was collected more often during the early stages of decomposition, followed by Chrysomya spp., Cochliomyia macellaria, and Phormia regina in the later stages. Lucilia coeruleiviridis was the only synchronous blow fly on the three carcasses; other blow fly species exhibited only site-specific synchrony. Using dichotomous correlations and analyses of variance, we demonstrated that blow fly-community succession was asynchronous among three alligators; however, Monte Carlo simulations indicate that there was some degree of synchrony between the carcasses.
Jin, Xin; Mukherjee, Kushal; Gupta, Shalabh; Ray, Asok; Phoha, Shashi; Damarla, Thyagaraju
This communication addresses real-time weapon classification by analysis of asynchronous acoustic data, collected from microphones on a sensor network. The weapon classification algorithm consists of two parts: (i) feature extraction from time-series data using symbolic dynamic filtering (SDF), and (ii) pattern classification based on the extracted features using the language measure (LM) and support vector machine (SVM). The proposed algorithm has been tested on field data, generated by firing of two types of rifles. The results of analysis demonstrate high accuracy and fast execution of the pattern classification algorithm with low memory requirements. Potential applications include simultaneous shooter localization and weapon classification with soldier-wearable networked sensors. (rapid communication)
Nguyen, Huu Phuc; De Miras, Jérôme; Charara, Ali; Eltabach, Mario; Bonnet, Stéphane
This paper proposes a new method to estimate the rotor speed of the asynchronous machine by looking at the estimation problem as a nonlinear optimal control problem. The behavior of the nonlinear plant model is approximated off-line as a prediction map using a numerical one-step time discretization obtained from simulations. At each time-step, the speed of the induction machine is selected satisfying the dynamic fitting problem between the plant output and the predicted output, leading the system to adopt its dynamical behavior. Thanks to the limitation of the prediction horizon to a single time-step, the execution time of the algorithm can be completely bounded. It can thus easily be implemented and embedded into a real-time system to observe the speed of the real induction motor. Simulation results show the performance and robustness of the proposed estimator.
Litz, D.C.; Haller, H.E. III.
An induction motor structure for use on the outside of a superconducting rotor comprising a cylindrical shell of solid and laminated, magnetic iron with squirrel cage windings embedded in the outer circumference of said shell is described. The sections of the shell between the superconducting windings of the rotor are solid magnetic iron. The sections of the shell over the superconducting windings are made of laminations of magnetic iron. These laminations are parallel to the axis of the machine and are divided in halves with the laminations in each half oriented in diagonal opposition so that the intersection of the laminations forms a V. This structure presents a relatively high reluctance to leakage flux from the superconducting windings in the synchronous operating mode, while presenting a low reluctance path to the stator flux during asynchronous operation
Knight, Samuel [O8953; Baker, Gavin Matthew; Gamell, Marc [Rutgers U; Hollman, David [08953; Sjaardema, Gregor [SNL; Kolla, Hemanth [SNL; Teranishi, Keita; Wilke, Jeremiah J; Slattengren, Nicole [SNL; Bennett, Janine Camille
Major exascale computing reports indicate a number of software challenges to meet the dramatic change of system architectures in near future. While several-orders-of-magnitude increase in parallelism is the most commonly cited of those, hurdles also include performance heterogeneity of compute nodes across the system, increased imbalance between computational capacity and I/O capabilities, frequent system interrupts, and complex hardware architectures. Asynchronous task-parallel programming models show a great promise in addressing these issues, but are not yet fully understood nor developed su ciently for computational science and engineering application codes. We address these knowledge gaps through quantitative and qualitative exploration of leading candidate solutions in the context of engineering applications at Sandia. In this poster, we evaluate MiniAero code ported to three leading candidate programming models (Charm++, Legion and UINTAH) to examine the feasibility of these models that permits insertion of new programming model elements into an existing code base.
James D. Carswell
Full Text Available Modern smartphones are a great platform for Location Based Services (LBS. While outdoor LBS for smartphones has proven to be very successful, indoor LBS for smartphones has not yet fully developed due to the lack of an accurate positioning technology. In this paper we present an accurate indoor positioning approach for commercial off-the-shelf (COTS smartphones that uses the innate ability of mobile phones to produce ultrasound, combined with Time-Difference-of-Arrival (TDOA asynchronous trilateration. We evaluate our indoor positioning approach by describing its strengths and weaknesses, and determine its absolute accuracy. This is accomplished through a range of experiments that involve variables such as position of control point microphones, position of phone within the room, direction speaker is facing and presence of user in the signal path. Test results show that our Lok8 (locate mobile positioning system can achieve accuracies better than 10 cm in a real-world environment.
Lenero-Bardallo, Juan Antonio; Bryn, D H; Hafliger, Philipp
This article investigates the potential of the first ever prototype of a vision sensor that combines tricolor stacked photo diodes with the bio-inspired asynchronous pixel event communication protocol known as Address Event Representation (AER). The stacked photo diodes are implemented in a 22 × 22 pixel array in a standard STM 90 nm CMOS process. Dynamic range is larger than 60 dB and pixels fill factor is 28%. The pixels employ either simple pulse frequency modulation (PFM) or a Time-to-First-Spike (TFS) mode. A heuristic linear combination of the chip's inherent pseudo colors serves to approximate RGB color representation. Furthermore, the sensor outputs can be processed to represent the radiation in the near infrared (NIR) band without employing external filters, and to color-encode direction of motion due to an asymmetry in the update rates of the different diode layers.
Rakovec, O.; Weerts, A. H.; Sumihar, J.; Uijlenhoet, R.
This study investigates the suitability of the asynchronous ensemble Kalman filter (AEnKF) and a partitioned updating scheme for hydrological forecasting. The AEnKF requires forward integration of the model for the analysis and enables assimilation of current and past observations simultaneously at a single analysis step. The results of discharge assimilation into a grid-based hydrological model (using a soil moisture error model) for the Upper Ourthe catchment in the Belgian Ardennes show that including past predictions and observations in the data assimilation method improves the model forecasts. Additionally, we show that elimination of the strongly non-linear relation between the soil moisture storage and assimilated discharge observations from the model update becomes beneficial for improved operational forecasting, which is evaluated using several validation measures.
Rakovec, O.; Weerts, A. H.; Sumihar, J.; Uijlenhoet, R.
This study investigates the suitability of the Asynchronous Ensemble Kalman Filter (AEnKF) and a partitioned updating scheme for hydrological forecasting. The AEnKF requires forward integration of the model for the analysis and enables assimilation of current and past observations simultaneously at a single analysis step. The results of discharge assimilation into a grid-based hydrological model for the Upper Ourthe catchment in the Belgian Ardennes show that including past predictions and observations in the data assimilation method improves the model forecasts. Additionally, we show that elimination of the strongly non-linear relation between the soil moisture storage and assimilated discharge observations from the model update becomes beneficial for improved operational forecasting, which is evaluated using several validation measures.
Hecht, Ariel; Kinnunen, Paivo; McNaughton, Brandon; Kopelman, Raoul
This paper presents a novel application of magnetic particles for biosensing, called label-acquired magnetorotation (LAM). This method is based on a combination of the traditional sandwich assay format with the asynchronous magnetic bead rotation (AMBR) method. In label-acquired magnetorotation, an analyte facilitates the binding of a magnetic label bead to a nonmagnetic solid phase sphere, forming a sandwich complex. The sandwich complex is then placed in a rotating magnetic field, where the rotational frequency of the sandwich complex is a function of the amount of analyte attached to the surface of the sphere. Here, we use streptavidin-coated beads and biotin-coated particles as analyte mimics, to be replaced by proteins and other biological targets in future work. We show this sensing method to have a dynamic range of two orders of magnitude.
Bandini, Stefania; Bonomi, Andrea; Vizzari, Giuseppe; Acconci, Vito
The term Ambient Intelligence refers to electronic environments that are sensitive and responsive to the presence of people; in the described scenario the environment itself is endowed with a set of sensors (to perceive humans or other physical entities such as dogs, bicycles, etc.), interacting with a set of actuators (lights) that choose their actions (i.e. state of illumination) in an attempt improve the overall experience of these users. The model for the interaction and action of sensors and actuators is an asynchronous Cellular Automata (CA) with memory, supporting a self-organization of the system as a response to the presence and movements of people inside it. The paper will introduce the model, as well as an ad hoc user interface for the specification of the relevant parameters of the CA transition rule that determines the overall system behaviour.
Wróbel, A.; Surma, W.
Nowadays, you cannot imagine the construction and operation of machines without the use of electric motors [13-15]. The proposed position is designed to allow testing of asynchronous three-phase motors. The position consists of a tested engine and the engine running as a load, both engines combined with a mechanical clutch . The value of the load is recorded by measuring shaft created with Strain Gauge Bridge. This concept will allow to study the basic parameters of the engines, visualization motor parameters both vector and scalar controlled, during varying load drive system. In addition, registration during the variable physical parameters of the working electric motor, controlled by a frequency converter or controlled by a contactor will be possible. Position is designed as a teaching and research position to characterize the engines. It will be also possible selection of inverter parameters.
Comeaux, David J.
Digital libraries continue to flourish. At the same time, the principles of user-centered design and the practice of usability testing have been growing in popularity, spreading their influence into the library sphere. This article explores the confluence of these two trends by surveying the current literature on usability studies of digital…
Koohang, Alex; Ondracek, James
This study examined users' views about the usability of digital libraries' current and perceived importance. Age, gender, prior experience with the Internet, college status, and digital library proficiency are the independent variables. Users' current views about the usability of digital libraries and users perceived importance of digital library…
Barlach, Anders; Hertzum, Morten; Simonsen, Jesper
This chapter reports on the usability-engineering work performed throughout the pilot implementation of an Electronic Healthcare Record (EHR). The case describes and analyzes the use of pilot implementations to formatively evaluate whether the usability of the EHR meets the effects specified for ...
Wijnhoven, Alphonsus B.J.M.; Heerkens, Johannes M.G.
This article analyzes the usability of a multi-criteria decision analysis based on a real options AHP (ROAHP) method for IT-investment decisions. The study presents ROAHP to Chief Information Officers (CIO’s) and collects their opinions on prerequisites for usability, strengths and weaknesses. To
Describes the redesign of the Web site at the virtual library of the NIST (National Institute of Standards and Technology). Discusses usability problems with the original site, including navigation difficulties; focus groups to determine user needs; usability testing for the new Web site; and the importance of customer input. (LRW)
Jameson, Daphne A.
The increasing availability of recording technologies makes it easier to include usability testing projects in business communication courses. Usability testing is a method of discovering whether people can navigate, read, and understand a print or electronic communication well enough to achieve a particular purpose in a reasonable time frame.…
Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi; Oudkerk, Matthijs; van Ooijen, Peter
Objective To evaluate the usability of a radiology workstation after deployment in a hospital. Significance In radiology, it is difficult to perform valid pre-deployment usability evaluations due to the heterogeneity of the user group, the complexity of the radiological workflow, and the complexity
Nielsen, Lene; Madsen, Sabine
This paper contributes to the HCI literature on usability practice with insights about the empirical challenges and global emerging practices caused by the advent of agile software development (ASD). In the paper we report from a worldwide study involving 12 usability professionals from 12 differ...
Chowdhury, G G
Gives an overview of the necessary issues relating to information users and the usability of information services in the digital world, including user-centred design, and the characteristics and behaviour of information users. This book helps readers understand why information users and the usability of information services are important.
Skov, Mikael Brasholt; Stage, Jan
Many efforts to improve the interplay between usability evaluation and software development rely either on better methods for conducting usability evaluations or on better formats for presenting evaluation results in ways that are useful for software designers and developers. Both of these approaches depend on a complete division of work between…
Nowadays, many users experience usability issues with their electronic products. It does not work as they expect or otherwise irritates the user, so he becomes dissatisfied about the product and may even complain about it. Th ese numbers of complaints to companies and usability issues are high and
Schultz, Nette; Kirk Sørensen, Jannick; Sørensen, Lene
Internal report of WP1 task 4 activities from August 2006 to December 2006. This report describes the setup of a usability evaluation framework for evaluating core MAGNET concepts in terms of usability. Initially, these core concepts are identified and modes of operation involving...
Cruz Zapata, Belén; Fernández-Alemán, José Luis; Toval, Ambrosio; Idri, Ali
One of the key factors for the adoption of mobile technologies, and in particular of mobile health applications, is usability. A usable application will be easier to use and understand by users, and will improve user's interaction with it. This paper proposes a software requirements catalog for usable mobile health applications, which can be used for the development of new applications, or the evaluation of existing ones. The catalog is based on the main identified sources in literature on usability and mobile health applications. Our catalog was organized according to the ISO/IEC/IEEE 29148:2011 standard and follows the SIREN methodology to create reusable catalogs. The applicability of the catalog was verified by the creation of an audit method, which was used to perform the evaluation of a real app, S Health, application created by Samsung Electronics Co. The usability requirements catalog, along with the audit method, identified several usability flaws on the evaluated app, which scored 83%. Some flaws were detected in the app related to the navigation pattern. Some more issues related to the startup experience, empty screens or writing style were also found. The way a user navigates through an application improves or deteriorates user's experience with the application. We proposed a reusable usability catalog and an audit method. This proposal was used to evaluate a mobile health application. An audit report was created with the usability issues identified on the evaluated application.
Chow, Anthony S.; Croxton, Rebecca A.
This study examined the usability of five virtual reference services--instant messenger chat, e-mail, telephone, text messaging, and Skype videoconferencing--by having 31 undergraduate and graduate students evaluate the usability of the virtual reference services of two different universities. The study's results suggest that user preference and…
Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi A.; Oudkerk, Matthijs; Van Ooijen, Peter M. A.
Objectives: To determine the number, nature and severity of usability issues radiologists encounter while using a commercially available radiology workstation in clinical practice, and to assess how well the results of a pre-deployment usability evaluation of this workstation generalize to clinical
Marcilly, Romaric; Peute, Linda
This paper discusses how and why to build evidence-based knowledge on usability evaluation methods. At each step of building evidence, requisites and difficulties to achieve it are highlighted. Specifically, the paper presents how usability evaluation studies should be designed to allow capitalizing
Campbell, Nicole; Walbridge, Sharon; Chisman, Janet; Diller, Karen R.
This interview focuses on usability testing, one method for evaluating whether library Web sites are useful for users. Discussion includes: benefits and drawbacks of usability testing; why it is important; lessons learned from testing; advice for someone interested in doing a study; and recommendations. (AEF)
Thyvalikakath, Thankam Paul; Monaco, Valerie; Thambuganipalle, Himabindu; Schleyer, Titus
Usability methods, such as heuristic evaluation, cognitive walk-throughs and user testing, are increasingly used to evaluate and improve the design of clinical software applications. There is still some uncertainty, however, as to how those methods can be used to support the development process and evaluation in the most meaningful manner. In this study, we compared the results of a heuristic evaluation with those of formal user tests in order to determine which usability problems were detected by both methods. We conducted heuristic evaluation and usability testing on four major commercial dental computer-based patient records (CPRs), which together cover 80% of the market for chairside computer systems among general dentists. Both methods yielded strong evidence that the dental CPRs have significant usability problems. An average of 50% of empirically-determined usability problems were identified by the preceding heuristic evaluation. Some statements of heuristic violations were specific enough to precisely identify the actual usability problem that study participants encountered. Other violations were less specific, but still manifested themselves in usability problems and poor task outcomes. In this study, heuristic evaluation identified a significant portion of problems found during usability testing. While we make no assumptions about the generalizability of the results to other domains and software systems, heuristic evaluation may, under certain circumstances, be a useful tool to determine design problems early in the development cycle.
Edward K. Lew
Full Text Available Background: Asynchronous learning is gaining popularity. Data are limited regarding this learning method in medical students rotating in emergency medicine (EM. In EM, faculty time is limited to give in-person lectures. The authors sought to create an online curriculum that students could utilize as an additional learning modality. Objective: The goal was to evaluate effectiveness, participation, and preference for this mode of learning. Methods: We developed five online, narrated PowerPoint presentations. After orientation, access to the online curriculum was provided to the students, which they could review at their leisure. Results: One hundred and seven fourth-year medical students participated. They reported the curriculum to be of high quality. Pretest scores were similar for those that viewed all lectures – compliant group (CG (9.5 [CI 4.8–14.1] and those that did not view any – non-compliant group (NCG (9.6 [CI 5.9–13.4]. There was no statistical significant difference in posttest scores between the groups although there was improvement overall: CG 14.6 (CI 6.9–22.1; NCG 11.4 (CI 5.7–17.1. A majority (69.2% favored inclusion of asynchronous learning, but less than a quarter (22.4% reported viewing all five modules and more than a third (36.4% viewed none. Conclusion: Despite student-expressed preference for an online curriculum, they used the online resource less than expected. This should give pause to educators looking to convert core EM topics to an online format. However, when high-quality online lectures are utilized as a learning tool, this study demonstrates that they had neither a positive nor a negative impact on test scores.
Full Text Available Usability of medical devices is one of the main determining factors in preventing use errors in treatment and strongly correlates to patient safety and quality of treatment. This thesis demonstrates the usability testing and evaluation of a prototype for locomotor therapy of infants. Therefore, based on the normative requirements of the EN 62366, a concept combined of evaluation procedures and assessing methods was created to enable extensive testing and analysis of the different aspects of usability. On the basis of gathered information weak points were identified and appropriate measures were presented to increase the usability and operating safety of the locomotor prototype. The overall outcome showed an usability value of 77.4% and an evaluation score of 6.99, which can be interpreted as “satisfactory”.
Gabbard, Joseph; Swan, J. E., II; Hix, Deborah; Lanzagorta, Marco O.; Livingston, Mark; Brown, Dennis B.; Julier, Simon J.
This paper discusses our usability engineering process for the Battlefield Augmented Reality System (BARS). Usability engineering is a structured, iterative, stepwise development process. Like the related disciplines of software and systems engineering, usability engineering is a combination of management principals and techniques, formal and semi- formal evaluation techniques, and computerized tools. BARS is an outdoor augmented reality system that displays heads- up battlefield intelligence information to a dismounted warrior. The paper discusses our general usability engineering process. We originally developed the process in the context of virtual reality applications, but in this work we are adapting the procedures to an augmented reality system. The focus of this paper is our work on domain analysis, the first activity of the usability engineering process. We describe our plans for and our progress to date on our domain analysis for BARS. We give results in terms of a specific urban battlefield use case we have designed.
Remote viewing is the supposed faculty which enables a percipient, sited in a closed room, to describe the perceptions of a remote agent visiting an unknown target site. To provide convincing demonstration of such a faculty poses a range of experimental and practical problems, especially if feedback to the percipient is allowed after each trial. The precautions needed are elaborate and troublesome; many potential loopholes have to be plugged and there will be strong temptations to relax standards, requiring exceptional discipline and dedication by the experimenters. Most reports of remote viewing experiments are rather superficial and do not permit assessment of the experimental procedures with confidence; in many cases there is clear evidence of particular loopholes left unclosed. Any serious appraisal of the evidence would have to go beyond the reports. Meanwhile the published evidence is far from compelling, and certainly insufficient to justify overthrow of well-established scientific principles.
Tiwari, Ashish; Dutertre, Bruno
We present formal models and results of formal analysis of two different asynchronous systems. We first examine a mid-value select module that merges the signals coming from three different sensors that are each asynchronously sampling the same input signal. We then consider the phase locking protocol proposed by Daly, Hopkins, and McKenna. This protocol is designed to keep a set of non-faulty (asynchronous) clocks phase locked even in the presence of Byzantine-faulty clocks on the network. All models and verifications have been developed using the SAL model checking tools and the Hybrid SAL abstractor.
Full Text Available The asynchronous systems are the non-deterministic real timebinarymodels of the asynchronous circuits from electrical engineering.Autonomy means that the circuits and their models have no input.Regularity means analogies with the dynamical systems, thus such systems may be considered to be real time dynamical systems with a’vector field’, Universality refers to the case when the state space of the system is the greatest possible in the sense of theinclusion. The purpose of this paper is that of defining, by analogy with the dynamical systems theory, the omega-limit sets, the invariance and the basins of attraction of the universal regular autonomous asynchronous systems.
Croft, K.; Hyde, R.; Allen, S.
The objective of the Digface Characterization (DFC) Remote Testing project is to remotely deploy a sensor head (Mini-Lab) across a digface to determine if it can characterize the contents below the surface. The purpose of this project is to provide a robotics technology that allows removal of workers from hazards, increases speed of operations, and reduces life cycle costs compared to alternate methods and technologies. The Buried Waste Integrated Demonstration (BWID) is funding the demonstration, testing, and evaluation of DFC. This document describes the test plan for the DFC remote deployment demonstration for the BWID. The purposes of the test plan are to establish test parameters so that the demonstration results are deemed useful and usable and perform the demonstration in a safe manner and within all regulatory requirements
This is an unrefined proposal for a study that could form part of the exploratory phase of the Cultural Usability project. The proposed study compares three cultures (Chinese, Danish, and Indian) and two stakeholder groups (users and developers) with respect to their conceptions of usability....
Watbled, Ludivine; Marcilly, Romaric; Guerlinger, Sandra; Bastien, J-M Christian; Beuscart-Zéphir, Marie-Catherine; Beuscart, Régis
Poor usability of health technology is thought to diminish work system performance, increase error rates and, potentially, harm patients. The present study (i) used a combination of usability evaluation methods to highlight the chain that leads from usability flaws to usage problems experienced by users and, ultimately, to negative patient outcomes, and (ii) validated this approach by studying two different discharge summary production systems. To comply with quality guidelines, the process of drafting and sending discharge summaries is increasingly being automated. However, the usability of these systems may modify their impact (or the absence thereof) in terms of production times and quality, and must therefore be evaluated. Here, we applied three successive techniques for usability evaluation (heuristic evaluation, user testing and field observation) to two discharge summary production systems (underpinned by different technologies). The systems' main usability flaws led respectively to an increase in the time need to produce a discharge summary and the risk of patient misidentification. Our results are discussed with regard to the possibility of linking the usability flaws, usage problems and the negative outcomes by successively applying three methods for evaluating usability (heuristic evaluation, user testing and in situ observations) throughout the system development life cycle. Copyright © 2018 Elsevier Inc. All rights reserved.
Sharp, Nathan; Kuntz, Alan; Brubaker, Cole; Amos, Stephanie; Gao, Wei; Gupta, Gautum; Mohite, Aditya; Farrar, Charles; Mascareñas, David
In many applications of structural health monitoring (SHM) it is imperative or advantageous to have large sensor arrays in order to properly sense the state of health of the structure. Typically these sensor networks are implemented by placing a large number of sensors over a structure and running individual cables from each sensor back to a central measurement station. Data is then collected from each sensor on the network at a constant sampling rate regardless of the current timescales at which events are acting on the structure. These conventional SHM sensor networks have a number of shortfalls. They tend to have a large number of cables that can represent a single point of failure for each sensor as well as add significant weight and installation costs. The constant sampling rate associated with each sensor very quickly leads to large amounts of data that must be analyzed, stored, and possibly transmitted to a remote user. This leads to increased demands on power consumption, bandwidth, and size. It also taxes our current techniques for managing large amounts of data. For the last decade the goal of the SHM community has been to endow structures with the functionality of a biological nervous system. Despite this goal the community has predominantly ignored the biological nervous system as inspiration for building structural nervous systems, choosing instead to focus on experimental mechanics and simulation techniques. In this work we explore the use of a novel, bio-inspired, SHM skin. This skin makes use of distributed computing and asynchronous communication techniques to alleviate the scale of the data management challenge as well as reduce power. The system also periodically sends a ‘heat beat’ signal to provide state-of-health updates. This conductive skin was implemented using conductive ink resistors as well as with graphene-oxide capacitors. (paper)
With Asynchronous Transfer Mode (ATM), we are experiencing the emergence of a network technology that has the potential of satisfying the requirement for a worldwide standard to allow interoperability of information, regardless...
Van hamme, Hugo
Van hamme H., ''Integration of asynchronous knowledge sources in a novel speech recognition framework'', Proceedings ITRW on speech analysis and processing for knowledge discovery, 4 pp., June 2008, Aalborg, Denmark.
Kreijns, K.; Kirschner, P.A.; Jochems, W.; Buuren, H. van
The effectiveness of group learning in asynchronous distributed learning groups depends on the social interaction that takes place. This social interaction affects both cognitive and socioemotional processes that take place during learning, group forming, establishment of group structures, and group
Dewiyanti, Silvia; Brand-Gruwel, Saskia; Jochems, Wim; Broers, Nick
Dewiyanti, S., Brand-Gruwel, S., Jochems, W., & Broers, N. (2007). Students experiences with collaborative learning in asynchronous computer-supported collaborative learning environments. Computers in Human Behavior, 23, 496-514.
Full Text Available In work some features of a mode of capacitor excitation of industrial asynchronous electric motors, and also generators made on their base which can be used in wind installations of low power are considered. Borders of zones of steady capacitor excitation of asynchronous electric motors in rated power of 0,25-22,0 kW and generators made on their base, and also character of influence of own losses and active capacity of loading of the equivalent circuit of the asynchronous machine resulted in parameters have been determined. Some recommendations after maintenance of stability of capacitor excitation of asynchronous machines for work in a mode of generation of electric energy are given.
Nielsen, Sune Fallgaard; Sparsø, Jens; Madsen, Jan
The current state-of-the art in high-level synthesis of asynchronous circuits is syntax directed translation, which performs a one-to-one mapping of a HDL-description into a corresponding circuit. This paper presents a method for behavioral synthesis of asynchronous circuits which builds on top...... description language Balsa . This ”conventional” template architecture allows us to adapt traditional synchronous synthesis techniques for resource sharing, scheduling, binding etc, to the domain of asynchronous circuits. A prototype tool has been implemented on top of the Balsa framework, and the method...... is illustrated through the implementation of a set of example circuits. The main contributions of the paper are: the fundamental idea, the template architecture and its implementation using asynchronous handshake components, and the implementation of a prototype tool....
Wu, Xiaotai; Tang, Yang; Cao, Jinde; Zhang, Wenbing
In this paper, the distributed exponential consensus of stochastic delayed multi-agent systems with nonlinear dynamics is investigated under asynchronous switching. The asynchronous switching considered here is to account for the time of identifying the active modes of multi-agent systems. After receipt of confirmation of mode's switching, the matched controller can be applied, which means that the switching time of the matched controller in each node usually lags behind that of system switching. In order to handle the coexistence of switched signals and stochastic disturbances, a comparison principle of stochastic switched delayed systems is first proved. By means of this extended comparison principle, several easy to verified conditions for the existence of an asynchronously switched distributed controller are derived such that stochastic delayed multi-agent systems with asynchronous switching and nonlinear dynamics can achieve global exponential consensus. Two examples are given to illustrate the effectiveness of the proposed method.
Kreijns, C.J.; Kirschner, P.A.; Jochems, W.M.G.; Buuren, van H.
The effectiveness of group learning in asynchronous distributed learning groups depends on the social interaction that takes place. This social interaction affects both cognitive and socioemotional processes that take place during learning, group forming, establishment of group structures, and group
Full Text Available An asynchronous VLSI implementation of the International Data Encryption Algorithm (IDEA is presented in this paper. In order to evaluate the asynchronous design a synchronous version of the algorithm was also designed. VHDL hardware description language was used in order to describe the algorithm. By using Synopsys commercial available tools the VHDL code was synthesized. After placing and routing both designs were fabricated with 0.6 μm CMOS technology. With a system clock of up to 8 MHz and a power supply of 5 V the two chips were tested and evaluated comparing with the software implementation of the IDEA algorithm. This new approach proves efficiently the lowest power consumption of the asynchronous implementation compared to the existing synchronous. Therefore, the asynchronous chip performs efficiently in Wireless Encryption Protocols and high speed networks.
National Aeronautics and Space Administration — SSCI proposes to develop, implement and test a collision detection system for unmanned aerial vehicles (UAV), referred to as the Asynchronous Sensor fuSion for...
Full Text Available Near Field Communication (NFC as relatively new wireless communication technology pushes new challenges to application developers to make their applications easier to use and simpler to operate. This point of view known as usability element. Usability is one of the elements for creating good quality applications. This study aims to analyse the usability of mobile-based application embeds with NFC. We also try to evaluate usability in applications used by children. We developed an application called Receptionist which has a primary function as a communication tool between students, teachers and parents at a middle school. To know the impact of the NFC, the Receptionist input system is designed with two methods, via conventional navigation (using buttons and via NFC. To understand the usability of each method, we do user testing and questioners on students. The results show, using the NFC there is a significant increase in usability attributes: efficiency, effectiveness, and learnability. On the other hand, there is decreases of user satisfaction comparing to conventional method. In general, this study demonstrates the potential of new input device technologies that can improve the usability of mobile-based applications.
Full Text Available “Reusable learning objects” oriented towards increasing their potential reusability are required to satisfy concerns about their granularity and their independence of concrete contexts of use. Such requirements also entail that the definition of learning object “usability,” and the techniques required to carry out their “usability evaluation” must be substantially different from those commonly used to characterize and evaluate the usability of conventional educational applications. In this article, a specific characterization of the concept of learning object usability is discussed, which places emphasis on “reusability,” the key property of learning objects residing in repositories. The concept of learning object reusability is described as the possibility and adequacy for the object to be usable in prospective educational settings, so that usability and reusability are considered two interrelated – and in many cases conflicting – properties of learning objects. Following the proposed characterization of two characteristics or properties of learning objects, a method to evaluate usability of specific learning objects will be presented.
Hussain, Azham; Mkpojiogu, Emmanuel O. C.; Almazini, Hassan; Almazini, Hussein
Like searching for a "needle" in a "haystack", suppose that there is a large set of signals (finite sequences of numbers) fs1; s2; s3; g, and a special signal q that may or may not be in the collection. How can the signals be found in the collection that is similar, or identical to q, and how can this be done quickly? A solution to this question is the basis of the Shazam smart phone app, where a listener captures a short excerpt of a recorded song with the smart phone's microphone, and in a matter of moments the app reports the name of the song and the artist. Here, the "needle" is the excerpt, and the "haystack" is a vast corpus of popular music. The Shazam algorithm is powered by Fourier analysis. This paper presents a report on a usability evaluation of Amazon Shazam app. The researchers present the outcome based on a task-based evaluation that involved 15 users of different level of experience who performed 5 tasks using the Shazam mobile app. Post-test questionnaire was used to capture users' perceptions about the app. The results demonstrate that most of the participants were satisfied with services provided by the app.
Rakovec, Oldrich; Weerts, Albrecht; Sumihar, Julius; Uijlenhoet, Remko
Hydrological forecasts can be made more reliable and less uncertain by recursively improving initial conditions. A common way of improving the initial conditions is to make use of data assimilation (DA), a feedback mechanism or update methodology which merges model estimates with available real world observations. The traditional implementation of the Ensemble Kalman Filter (EnKF; e.g. Evensen, 2009) is synchronous, commonly named a three dimensional (3-D) assimilation, which means that all assimilated observations correspond to the time of update. Asynchronous DA, also called four dimensional (4-D) assimilation, refers to an updating methodology, in which observations being assimilated into the model originate from times different to the time of update (Evensen, 2009; Sakov 2010). This study investigates how the capabilities of the DA procedure can be improved by applying alternative Kalman-type methods, e.g., the Asynchronous Ensemble Kalman Filter (AEnKF). The AEnKF assimilates observations with smaller computational costs than the original EnKF, which is beneficial for operational purposes. The results of discharge assimilation into a grid-based hydrological model for the Upper Ourthe catchment in Belgian Ardennes show that including past predictions and observations in the AEnKF improves the model forecasts as compared to the traditional EnKF. Additionally we show that elimination of the strongly non-linear relation between the soil moisture storage and assimilated discharge observations from the model update becomes beneficial for an improved operational forecasting, which is evaluated using several validation measures. In the current study we employed the HBV-96 model built within a recently developed open source modelling environment OpenStreams (2013). The advantage of using OpenStreams (2013) is that it enables direct communication with OpenDA (2013), an open source data assimilation toolbox. OpenDA provides a number of algorithms for model calibration
Andrade Martins, R. de (Centro de Logica, Epistemologia e Historia da Ciencia, Campinas (Brazil))
In the recently developed asynchronous formulation of the relativistic theory of extended bodies, the inertial mass of a body does not explicitly depend on its pressure or stress. The detailed analysis of the weight of a box filled with a gas and placed in a weak gravitational field shows that this feature of asynchronous relativity implies a breakdown of the equivalence between inertial and passive gravitational mass for stressed systems.
a circuit remain fixed during the entire simulation. We remove this limitation and, by extending the analyses to multi-input, multi-output circuits with an arbitrary number of input events, show that the conservative asynchronous simulation extracts more parallelism and executes faster than synchronous simulation in general. Our conclusions are supported by a comparison of the idealized execution times of synchronous and conservative asynchronous algorithms on ISCAS combinational and sequential benchmark circuits.
Jurado-Navas, Antonio; Raddo, Thiago R.; Sanches, Anderson L.
We propose a new hybrid asynchronous OCDMA-FSO communications system for access network solutions. New ABER expressions are derived under gamma-gamma scintillation channels, where all users can surprisingly achieve error-free transmissions when FEC is employed.......We propose a new hybrid asynchronous OCDMA-FSO communications system for access network solutions. New ABER expressions are derived under gamma-gamma scintillation channels, where all users can surprisingly achieve error-free transmissions when FEC is employed....
Strict optical orthogonal codes are presented for purely asynchronous optical code-division multiple-access (CDMA) applications. The proposed code can strictly guarantee the peaks of its cross-correlation functions and the sidelobes of any of its autocorrelation functions to have a value of 1 in purely asynchronous data communications. The basic theory of the proposed codes is given. An experiment on optical CDMA systems is also demonstrated to verify the characteristics of the proposed code.
Alexandru Bârlea; Olivian Chiver
Starting synchronous motors can be achieved by several ethods: starting with an auxiliary motor launch, starting in asynchronous regim, by feeding from a variable frequency source, auto-synchronization with the network.. In our case we study the transient processes in a asynchronous regim . In this case the synchronous motor is started like a squirrel cage induction motor . To start, the synchronous motor is equipped with a starting winding cage placed in the pole pieces of polar inducers; la...
Reviakin, Y; Sukhanov, A
Introduction Common telemedicine consultations can be divided in two classes: real-time telemedicine consultations and asynchronous telemedicine consultations. The advantage of real-time consultations is obvious - this is a natural discussion between physicians, which may be realised on the basis of desktop videoconferences. But the problems are also obvious: the necessity of additional hardware and the elevated demands for channel bandwidth. Because of the latter, the use of asynchronous tel...
. This paper presents a comprehensive literature study of research conducted in this area, where 129 papers are analyzed in terms of research focus, empirical basis, types of training participants and training costs. Findings show a need for further empirical research regarding long term effects of training...... to fund usability specialists or comprehensive consultancy. Training of non-usability personnel in critical usability engineering methods has the potential of easing these challenges. It is, however, unknown how much and what kind of research that has been committed to novice training in UE methods......, training costs and training in user based evaluation methods....
Nielsen, C. M.; Overgaard, M.; Pedersen, M. B.
This paper reports from an exploratory study of means for providing feedback from a usability evaluation to the user interface designers. In this study, we conducted a usability evaluation of a mobile system that is used by craftsmen to register use of time and materials. The results...... and weaknesses of the system. The findings indicate that detailed descriptions of problems and log descriptions of the user's interaction with the system and of system interaction are useful for the designers when trying to understand the usability problems that the users have encountered....
Clemmensen, Torkil; Ørngreen, Rikke; Roese, Kerstin
it into interaction design. The workshop will present current research into cultural usability and human work interaction design. Cultural usability is a comprehensive concept, which adheres to all kinds of contexts in which humans are involved (private family, work, public and private organizations, nature......, Workplace observation, Think-Aloud Usability Test, etc. These techniques often give - seemingly - similar results when applied in diverse cultural settings, but experience shows that we need a deep understanding of the cultural, social and organizational context to interpret the results, and to transform...
Teka, Degif; Dittrich, Y.; Kifle, Mesfin
be adapted and integrated into the Scrum-agile development with especial emphasis on the Ethiopian context. The research aims at adapting software engineering and ICT development methods to the specific situation and integrating user-centered design (UCD) and lightweight usability methods into agile...... end users and developers. Culturally adapted user pair testing and heuristic evaluation supported usability testing and supported developers in getting early feedback. Integrated approach of discount usability with the Scrum process has been developed and evaluated first with the involved...
Full Text Available Abstract Background With increasing knowledge about the potential mechanisms underlying cellular functions, it is becoming feasible to predict the response of biological systems to genetic and environmental perturbations. Due to the lack of homogeneity in living tissues it is difficult to estimate the physiological effect of chemicals, including potential toxicity. Here we investigate a biologically motivated model for estimating tissue level responses by aggregating the behavior of a cell population. We assume that the molecular state of individual cells is independently governed by discrete non-deterministic signaling mechanisms. This results in noisy but highly reproducible aggregate level responses that are consistent with experimental data. Results We developed an asynchronous threshold Boolean network simulation algorithm to model signal transduction in a single cell, and then used an ensemble of these models to estimate the aggregate response across a cell population. Using published data, we derived a putative crosstalk network involving growth factors and cytokines - i.e., Epidermal Growth Factor, Insulin, Insulin like Growth Factor Type 1, and Tumor Necrosis Factor α - to describe early signaling events in cell proliferation signal transduction. Reproducibility of the modeling technique across ensembles of Boolean networks representing cell populations is investigated. Furthermore, we compare our simulation results to experimental observations of hepatocytes reported in the literature. Conclusion A systematic analysis of the results following differential stimulation of this model by growth factors and cytokines suggests that: (a using Boolean network ensembles with asynchronous updating provides biologically plausible noisy individual cellular responses with reproducible mean behavior for large cell populations, and (b with sufficient data our model can estimate the response to different concentrations of extracellular ligands. Our
Foster, I.; Kohr, D., Jr.; Krishnaiyer, R.; Mogill, J.
As high-speed networks make it easier to use distributed resources, it becomes increasingly common that applications and their data are not colocated. Users have traditionally addressed this problem by manually staging data to and from remote computers. We argue instead for a new remote I/O paradigm in which programs use familiar parallel I/O interfaces to access remote file systems. In addition to simplifying remote execution, remote I/O can improve performance relative to staging by overlapping computation and data transfer or by reducing communication requirements. However, remote I/O also introduces new technical challenges in the areas of portability, performance, and integration with distributed computing systems. We propose techniques designed to address these challenges and describe a remote I/O library called RIO that we have developed to evaluate the effectiveness of these techniques. RIO addresses issues of portability by adopting the quasi-standard MPI-IO interface and by defining a RIO device and RIO server within the ADIO abstract I/O device architecture. It addresses performance issues by providing traditional I/O optimizations such as asynchronous operations and through implementation techniques such as buffering and message forwarding to off load communication overheads. RIO uses the Nexus communication library to obtain access to configuration and security mechanisms provided by the Globus wide area computing tool kit. Microbenchmarks and application experiments demonstrate that our techniques achieve acceptable performance in most situations and can improve turnaround time relative to staging.
Kunin, Marc; Julliard, Kell N; Rodriguez, Tobias E
The Department of Dental Medicine of Lutheran Medical Center has developed an asynchronous online curriculum consisting of prerecorded PowerPoint presentations with audio explanations. The focus of this study was to evaluate if the new asynchronous format satisfied the educational needs of the residents compared to traditional lecture (face-to-face) and synchronous (distance learning) formats. Lectures were delivered to 219 dental residents employing face-to-face and synchronous formats, as well as the new asynchronous format; 169 (77 percent) participated in the study. Outcomes were assessed with pretests, posttests, and individual lecture surveys. Results found the residents preferred face-to-face and asynchronous formats to the synchronous format in terms of effectiveness and clarity of presentations. This preference was directly related to the residents' perception of how well the technology worked in each format. The residents also rated the quality of student-instructor and student-student interactions in the synchronous and asynchronous formats significantly higher after taking the lecture series than they did before taking it. However, they rated the face-to-face format as significantly more conducive to student-instructor and student-student interaction. While the study found technology had a major impact on the efficacy of this curricular model, the results suggest that the asynchronous format can be an effective way to teach a postgraduate course.
Makris, L; Kamilatos, I; Kopsacheilis, E V; Strintzis, M G
The present paper describes methods for the design of both synchronous and asynchronous computer-supported cooperative work (CSCW) procedures suitable for the medical application area and specifically for the purpose of medical teleconsultation and remote diagnosis support. The experimental implementation of a CSCW system built upon a PC/Windows platform is detailed as an example of a low-cost system suitable for adoption in a wide range of medical teleconsultation applications.
De Sa, Christopher; Feldman, Matthew; Ré, Christopher; Olukotun, Kunle
Stochastic gradient descent (SGD) is one of the most popular numerical algorithms used in machine learning and other domains. Since this is likely to continue for the foreseeable future, it is important to study techniques that can make it run fast on parallel hardware. In this paper, we provide the first analysis of a technique called Buckwild! that uses both asynchronous execution and low-precision computation. We introduce the DMGC model, the first conceptualization of the parameter space that exists when implementing low-precision SGD, and show that it provides a way to both classify these algorithms and model their performance. We leverage this insight to propose and analyze techniques to improve the speed of low-precision SGD. First, we propose software optimizations that can increase throughput on existing CPUs by up to 11×. Second, we propose architectural changes, including a new cache technique we call an obstinate cache, that increase throughput beyond the limits of current-generation hardware. We also implement and analyze low-precision SGD on the FPGA, which is a promising alternative to the CPU for future SGD systems. PMID:29391770
Full Text Available This study examines the use of e-mail as a tool for long term discussion between teachers and grade six students. E-mail messages between grade six students and teachers were collected over the course of one academic year. Methods of conversation analysis within a framework of social practice are used to examine the data. While identity is more readily constructed and more fully developed in contexts which allow for physical embodiment such as face-to-face discussion, this analysis found that identity can be constructed in a context that does not provide for the physical embodiment of identity: Identity was constructed using the social, cultural, and technological tools provided and supported by e-mail to develop social practices germane to the e-mail discussion. This study has implications for further understanding the relation between identity, goals, constraints and affordances, and the collaborative creation of social practices in asynchronous computer mediated communication. URN: urn:nbn:de:0114-fqs0803185
Milstead, J A; Nelson, R
This article addresses the development of the initial course in the first completely online doctoral program in nursing. Synchronous and asynchronous methods of distance education were assessed. Planning focused at the university, school, and course levels. University planning involved the technical infrastructure, registration, student services, and library services. School planning examined administrative commitment and faculty commitment and willingness. Course planning focused on marketing, precourse information, time frame, modular design, planned interaction, and professor availability and support. Implementation issues centered on getting students connected, learning the software, changing instructional methods, and managing chats. Traditional methods of evaluating student learning and course evaluation were supplemented with the development of qualitative and quantitative tools to gather data for making administrative decisions. The Dean and faculty agreed that the internet was an effective method of delivering content in the initial Health Policy course. The Dean and faculty agreed to continue the PhD program online for one cohort and continue to evaluate student progress and faculty and student satisfaction.
Kramer, T; Bracco, C; Goddard, B; Meddahi, M
The LHC beam dump system has to safely dispose all beams in a wide energy range of 450 GeV to 7 TeV. A 3 ms abort gap in the beam structure for the switch-on of the extraction kicker field ideally allows a loss-free extraction under normal operating conditions. However, a low number of asynchronous beam aborts is to be expected from reliability calculations and from the first year's operational experience with the beam dump kickers. For such cases, MAD-X simulations including all optics and alignment errors have been performed to determine loss patterns around the LHC as a function of the position of the main protection elements in interaction region six. Special attention was paid to the beam load on the tungsten collimators which protect the triplets in the LHC experimental insertions, and the tracking results compared with semi-analytical numerical estimates. The simulations are also compared to the results of beam commissioning of these protection devices.
Harnarinesingh, Randy E S; Syan, Chanan S
The inherent noise associated with odometry manifests itself as errors in localization for autonomous vehicles. Visual odometry has been previously used in order to supplement classical vehicle odometry. However, visual odometry is limited in its ability to reduce errors in localization for large travel distances that entail the cumulative summing of individual frame-to-frame image errors. In this paper, a novel machine vision approach for tiled surfaces is proposed to address this problem. Tile edges in a laboratory environment are used to define a travel trajectory for the Quansar Qbot (autonomous vehicle) built on the iRobot iRoomba platform with a forward facing camera. Tile intersections are used to enable asynchronous error recovery for vehicle position and orientation. The proposed approach employs real-time image classification and is feasible for error mitigation for large travel distances. The average position error for an 8m travel distance using classical odometry was measured to be 0.28m. However, implementation of the proposed approach resulted in an error of 0.028m. The proposed approach therefore significantly reduces pose estimation error and could be used to supplement existing modalities such as GPS and Laser-based range sensors
Klimke, Jan; Döllner, Jürgen
This paper presents an approach for combining spatially distributed synchronous and asynchronous collaboration within 3D city models. Software applications use these models as additional communication medium to facilitate communication of georeferenced and geospatial information. Collaboration tools should support both the communication with other collaborators and their awareness of the current collaboration context. To support collaborative knowledge construction and gathering, we have designed a collaboration system to facilitate (a) creation of annotations that have 3D references to the virtual 3D city model and (b) collection information about the context in which these annotations are created. Our approach supports synchronous collaboration in connection with the creation of non volatile, precisely georeferenced units of information allow for a comprehensible form of cooperation in spatially distributed settings. Storage and retrieval of this information is provided through a Web Feature Service, which eases integration of collaboration data into existing applications. We further introduce a visualization technique that integrates annotations as complex structured data into the 3D visualization. This avoids media breaks and disruptions in working processes and creates a spatial coherence between annotation and annotated feature or geometry.
Garg, Abhishek; Di Cara, Alessandro; Xenarios, Ioannis; Mendoza, Luis; De Micheli, Giovanni
In silico modeling of gene regulatory networks has gained some momentum recently due to increased interest in analyzing the dynamics of biological systems. This has been further facilitated by the increasing availability of experimental data on gene-gene, protein-protein and gene-protein interactions. The two dynamical properties that are often experimentally testable are perturbations and stable steady states. Although a lot of work has been done on the identification of steady states, not much work has been reported on in silico modeling of cellular differentiation processes. In this manuscript, we provide algorithms based on reduced ordered binary decision diagrams (ROBDDs) for Boolean modeling of gene regulatory networks. Algorithms for synchronous and asynchronous transition models have been proposed and their corresponding computational properties have been analyzed. These algorithms allow users to compute cyclic attractors of large networks that are currently not feasible using existing software. Hereby we provide a framework to analyze the effect of multiple gene perturbation protocols, and their effect on cell differentiation processes. These algorithms were validated on the T-helper model showing the correct steady state identification and Th1-Th2 cellular differentiation process. The software binaries for Windows and Linux platforms can be downloaded from http://si2.epfl.ch/~garg/genysis.html.
Bentley, Richard S
.... This research effort seeks to establish an understanding of how well common practice usability design principles and government mandated accessibility guidelines are followed by Air Force intranet web sites...
Johansen, Sune Alstrup; Noergaard, Mie; Soerensen, Janus Rau
Good computer games need to be challenging while at the same time being easy to use. Accordingly, besides struggling with well known challenges for usability work, such as persuasiveness, the computer game industry also faces system-specific challenges, such as identifying methods that can provide...... data on players' attention during a game. This position paper discusses how eye tracking may address three core challenges faced by computer game producer IO Interactive in their on-going work to ensure games that are fun, usable, and challenging. These challenges are: (1) Persuading game designers...... about the relevance of usability results, (2) involving game designers in usability work, and (3) identifying methods that provide new data about user behaviour and experience....
Skov, Mikael B.; Stage, Jan
is based on an empirical study where 36 teams with a total of 234 first-year university students on software development and design educations were trained in a simple approach for user-based website usability testing that was taught in a 40 hour course. This approach supported them in planning, conducting......Many improvements of the interplay between usability evaluation and software development rely either on better methods for conducting usability evaluations or on better formats for presenting evaluation results in ways that are useful for software designers and developers. Both approaches involve...... a complete division of work between developers and evaluators, which is an undesirable complexity for many software development projects. This paper takes a different approach by exploring to what extent software developers and designers can be trained to carry out their own usability evaluations. The paper...
Haan, de G.; Terken, J.M.B.
This paper discusses usability research concerning a wearable system for spoken advice: a field experiment to investigate key concepts, a laboratory experiment to investigate interaction design, and field trials to evaluate the system. Conclusions are drawn about designing wearable appliances.
The reliability and usability of district health information software: case studies from Tanzania. ... The District Health Information System (DHIS) software from the Health Information System ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT
U.S. Department of Health & Human Services — Availability and Usability of Behavioral Health Organization Encounter Data in MAX 2009, published in Volume 4, Issue 2 of Medicare and Medicaid Research Review,...
Hornbæk, Kasper Anders Søren; Effie Lai Chong, Law
are generally low: effectiveness measures (e.g., errors) and efficiency measures (e.g., time) has a correlation of .247 ± .059 (Pearson's product-moment correlation with 95% confidence interval), efficiency and satisfaction (e.g., preference) one of .196 ± .064, and effectiveness and satisfaction one of .164......Understanding the relation between usability measures seems crucial to deepen our conception of usability and to select the right measures for usability studies. We present a meta-analysis of correlations among usability measures calculated from the raw data of 73 studies. Correlations...... ± .062. Changes in task complexity do not influence these correlations, but use of more complex measures attenuates them. Standard questionnaires for measuring satisfaction appear more reliable than homegrown ones. Measures of users' perceptions of phenomena are generally not correlated with objective...
Jensen, Janne Jul
social context is considered important, only little research has been done to identify how it influences usability evaluations. In this thesis I explore how social context affects the process and product of a usability evaluation and explain the findings in terms of the theory of behaviour settings...... leader) and non-operatives (members, spectators, neutrals and potentials) from the theory of behaviour settings to usability evaluations generates an understanding and create an awareness of the level of power possessed by each of the participants in the social context. 2. On the operative level...... and a field experiment. Findings from these activities are presented in five published paper contributions. I furthermore introduce the theory of behaviour settings as a tool to help characterise the key concepts of social context which, together with an understanding of usability evaluations, provide...
... has ever used the API; hence, no analysis was accomplished with respect to usability attributes, The project sponsor desires public release of the API, especially within the Department of Defense (DoD...
Mathew, Gloriya; Thomas, Shiney
User authentication is one of the most important part of information security. Computer security most commonly depends on passwords to authenticate human users. Password authentication systems will be either been usable but not secure, or secure but not usable. While there are different types of authentication systems available alphanumeric password is the most commonly used authentication mechanism. But this method has significant drawbacks. An alternative solution to the text based authenti...
Yen, Po-Yin; Wantland, Dean; Bakken, Suzanne
We developed a customizable questionnaire, the Health Information Technology (IT) Usability Evaluation Scale (Health-ITUES) and conducted an exploratory factor analysis to examine the scale’s psychometric properties. Nurses (n=377) completed Health-ITUES to rate the usability of a web-based communication system for scheduling nursing staff. The analysis revealed a four-factor structure of Health-ITUES. The results provided preliminary evidence for the factorial validity and internal consistency reliability of Health-ITUES. PMID:21347112
Tracking user activities online can be done in order to improve systems usability, understand user behaviour or to increase monetary prot, to mention a few things. The software tools for this purpose can vary, for example in terms of usability of the tool itself, features, security, price, accessibility and support options. In this study I have developed a methodology to evaluate a selection of modern tools and map them depending on various properties. I have also analysed learning theories t...
Romano, C.; Gay, P.; Owens, R.; Burlea, G.
Citizen science projects must undergo usability testing and optimization if they are to meet their stated goals. This presentation will include video of usability tests conducted upon citizen science websites. Usability testing is essential to the success of online interaction, however, citizen science projects have just begun to include this critical activity. Interaction standards in citizen science lag behind those of commercial interests, and published research on this topic is limited. Since online citizen science is by definition, an exchange of information, a clear understanding of how users experience an online project is essential to informed decision-making. Usability testing provides that insight. Usability testing collects data via direct observation of a person while she interacts with a digital product, such as a citizen science website. The test participant verbalizes her thoughts while using the website or application; the moderator follows the participant and captures quantitative measurement of the participant's confidence of success as she advances through the citizen science project. Over 15 years of usability testing, we have observed that users who do not report a consistent sense of progress are likely to abandon a website after as few as three unrewarding interactions. Since citizen science is also a voluntary activity, ensuring seamless interaction for users is mandatory. Usability studies conducted on citizen science websites demonstrate that project teams frequently underestimate a user's need for context and ease of use. Without usability testing, risks to online citizen science projects include high bounce rate (users leave the website without taking any action), abandonment (of the website, tutorials, registration), misunderstanding instructions (causing disorientation and erroneous conclusions), and ultimately, underperforming projects.
Nicholas Kipkurui Kiget; Professor G. Wanyembi; Anselemo Ikoha Peters
The use of e-learning systems has increased significantly in the recent times. E-learning systems are supplementing teaching and learning in universities globally. Kenyan universities have adopted e-learning technologies as means for delivering course content. However despite adoption of these systems, there are considerable challenges facing the usability of the systems. Lecturers and students have different perceptions in regard to the usability of e-learning systems. The aim of this study ...
Background Asynchronous, computer based instruction is cost effective, allows self-directed pacing and review, and addresses preferences of millennial learners. Current research suggests there is no significant difference in learning compared to traditional classroom instruction. Data are limited for novice learners in emergency medicine. The objective of this study was to compare asynchronous, computer-based instruction with traditional didactics for senior medical students during a week-long intensive course in acute care. We hypothesized both modalities would be equivalent. Methods This was a prospective observational quasi-experimental study of 4th year medical students who were novice learners with minimal prior exposure to curricular elements. We assessed baseline knowledge with an objective pre-test. The curriculum was delivered in either traditional lecture format (shock, acute abdomen, dyspnea, field trauma) or via asynchronous, computer-based modules (chest pain, EKG interpretation, pain management, trauma). An interactive review covering all topics was followed by a post-test. Knowledge retention was measured after 10 weeks. Pre and post-test items were written by a panel of medical educators and validated with a reference group of learners. Mean scores were analyzed using dependent t-test and attitudes were assessed by a 5-point Likert scale. Results 44 of 48 students completed the protocol. Students initially acquired more knowledge from didactic education as demonstrated by mean gain scores (didactic: 28.39% ± 18.06; asynchronous 9.93% ± 23.22). Mean difference between didactic and asynchronous = 18.45% with 95% CI [10.40 to 26.50]; p = 0.0001. Retention testing demonstrated similar knowledge attrition: mean gain scores −14.94% (didactic); -17.61% (asynchronous), which was not significantly different: 2.68% ± 20.85, 95% CI [−3.66 to 9.02], p = 0.399. The attitudinal survey revealed that 60.4% of students believed the asynchronous
Jordan, Jaime; Jalali, Azadeh; Clarke, Samuel; Dyne, Pamela; Spector, Tahlia; Coates, Wendy
Asynchronous, computer based instruction is cost effective, allows self-directed pacing and review, and addresses preferences of millennial learners. Current research suggests there is no significant difference in learning compared to traditional classroom instruction. Data are limited for novice learners in emergency medicine. The objective of this study was to compare asynchronous, computer-based instruction with traditional didactics for senior medical students during a week-long intensive course in acute care. We hypothesized both modalities would be equivalent. This was a prospective observational quasi-experimental study of 4th year medical students who were novice learners with minimal prior exposure to curricular elements. We assessed baseline knowledge with an objective pre-test. The curriculum was delivered in either traditional lecture format (shock, acute abdomen, dyspnea, field trauma) or via asynchronous, computer-based modules (chest pain, EKG interpretation, pain management, trauma). An interactive review covering all topics was followed by a post-test. Knowledge retention was measured after 10 weeks. Pre and post-test items were written by a panel of medical educators and validated with a reference group of learners. Mean scores were analyzed using dependent t-test and attitudes were assessed by a 5-point Likert scale. 44 of 48 students completed the protocol. Students initially acquired more knowledge from didactic education as demonstrated by mean gain scores (didactic: 28.39% ± 18.06; asynchronous 9.93% ± 23.22). Mean difference between didactic and asynchronous = 18.45% with 95% CI [10.40 to 26.50]; p = 0.0001. Retention testing demonstrated similar knowledge attrition: mean gain scores -14.94% (didactic); -17.61% (asynchronous), which was not significantly different: 2.68% ± 20.85, 95% CI [-3.66 to 9.02], p = 0.399. The attitudinal survey revealed that 60.4% of students believed the asynchronous modules were educational and 95
Full Text Available Nowadays there are different evaluation methods focused in the assessment of the usability of telematic methods. The assessment of 3rd generation web environments evaluates the effectiveness and usability of application with regard to the user needs. Wireless usability and, specifically in mobile phones, is concentrated in the validation of the features and tools management using conventional interactive environments. There is not a specific and suitable criterion to evaluate created environments and m-learning platforms, where the restricted and sequential representation is a fundamental aspect to be considered.The present paper exposes the importance of the conventional usability methods to verify both: the employed contents in wireless formats, and the possible interfaces from the conception phases, to the validations of the platform with such characteristics.The development of usability adapted inspection could be complemented with the Remote’s techniques of usability testing, which are being carried out these days in the mobile devices field and which pointed out the need to apply common criteria in the validation of non-located learning scenarios.
Pulantara, I Wayan; Parmanto, Bambang; Germain, Anne
supplement the subjective assessment of patient sleep patterns. The iREST app was developed from the mobile logical architecture of Just in Time Adaptive Intervention. It consists of a cross-platform smartphone app, a clinician portal, and secure 2-way communications platform between the app and the portal. The usability study comprised 19 Active Duty Service Members and Veterans between the ages of 18 and 60. Descriptive statistics based on in-app questionnaires indicate that on average, 12 (mean 12.23, SD 8.96) unique devices accessed the clinician portal per day for more than two years, while the app was rated as "highly usable", achieving a mean System Usability Score score of 85.74 (SD 12.37), which translates to an adjective rating of "Excellent". The participants also gave high scores on "ease of use and learnability" with an average score of 4.33 (SD 0.65) on a scale of 1 to 5. iREST provides a feasible platform for the implementation of Just in Time Adaptive Intervention in mHealth-based and remote intervention settings. The system was rated highly usable and its cross-platformness made it readily implemented within the heavily segregated smartphone market. The use of wearables to track sleep is promising; yet the accuracy of this technology needs further improvement. Ultimately, iREST demonstrates that mHealth-based Just in Time Adaptive Intervention is not only feasible, but also works effectively. ©I Wayan Pulantara, Bambang Parmanto, Anne Germain. Originally published in JMIR Human Factors (http://humanfactors.jmir.org), 17.05.2018.
Chang, Todd P; Pham, Phung K; Sobolewski, Brad; Doughty, Cara B; Jamal, Nazreen; Kwan, Karen Y; Little, Kim; Brenkert, Timothy E; Mathison, David J
Asynchronous e-learning allows for targeted teaching, particularly advantageous when bedside and didactic education is insufficient. An asynchronous e-learning curriculum has not been studied across multiple centers in the context of a clinical rotation. We hypothesize that an asynchronous e-learning curriculum during the pediatric emergency medicine (EM) rotation improves medical knowledge among residents and students across multiple participating centers. Trainees on pediatric EM rotations at four large pediatric centers from 2012 to 2013 were randomized in a Solomon four-group design. The experimental arms received an asynchronous e-learning curriculum consisting of nine Web-based, interactive, peer-reviewed Flash/HTML5 modules. Postrotation testing and in-training examination (ITE) scores quantified improvements in knowledge. A 2 × 2 analysis of covariance (ANCOVA) tested interaction and main effects, and Pearson's correlation tested associations between module usage, scores, and ITE scores. A total of 256 of 458 participants completed all study elements; 104 had access to asynchronous e-learning modules, and 152 were controls who used the current education standards. No pretest sensitization was found (p = 0.75). Use of asynchronous e-learning modules was associated with an improvement in posttest scores (p effect (partial η(2) = 0.19). Posttest scores correlated with ITE scores (r(2) = 0.14, p e-learning is an effective educational tool to improve knowledge in a clinical rotation. Web-based asynchronous e-learning is a promising modality to standardize education among multiple institutions with common curricula, particularly in clinical rotations where scheduling difficulties, seasonality, and variable experiences limit in-hospital learning. © 2014 by the Society for Academic Emergency Medicine.
It has been reported that more than half of the children in Japan suffer from daytime sleepiness. In contrast, about one quarter of junior high-school students in Japan complain of insomnia. According to the International Classification of Sleep Disorders (Second edition), these children could be diagnosed as having behaviorally-induced insufficient sleep syndrome due to inadequate sleeping habits. Getting on adequate amount of sleep should solve such problems;however, such a therapeutic approach often fails. Although social factors are involved in these sleep disturbances, I feel that a novel notion - asynchronization - leads to an understanding of the pathophysiology of disturbances in these children. Further, it could contribute to resolve their problems. The essence of asynchronization is a disturbance of various aspects (e.g., cycle, amplitude, phase, and interrelationship) of the biological rhythms that normally exhibits circadian oscillation. The main cause of asynchronization is hypothesized to be the combination of light exposure during night and the lack of light exposure in the morning. Asynchronization results in the disturbance of variable systems. Thus, symptoms of asynchronization include disturbances of the autonomic nervous system (sleepiness, insomnia, disturbance of hormonal excretion, gastrointestinal problems, etc.) and higher brain function (disorientation, loss of sociality, loss of will or motivation, impaired alertness and performance, etc.). Neurological (attention deficit, aggression, impulsiveness, hyperactivity, etc.), psychiatric (depressive disorders, personality disorders, anxiety disorders, etc.) and somatic (tiredness, fatigue, etc.) disturbances could also be symptoms of asynchronization. At the initial phase of asynchronization, disturbances are functional and can be resolved relatively easily, such as by the establishment of a regular sleep-wakefulness cycle;however, without adequate intervention the disturbances could gradually
Schnall, Rebecca; Cho, Hwayoung; Liu, Jianfang
Mobile technology has become a ubiquitous technology and can be particularly useful in the delivery of health interventions. This technology can allow us to deliver interventions to scale, cover broad geographic areas, and deliver technologies in highly tailored ways based on the preferences or characteristics of users. The broad use of mobile technologies supports the need for usability assessments of these tools. Although there have been a number of usability assessment instruments developed, none have been validated for use with mobile technologies. The goal of this work was to validate the Health Information Technology Usability Evaluation Scale (Health-ITUES), a customizable usability assessment instrument in a sample of community-dwelling adults who were testing the use of a new mobile health (mHealth) technology. A sample of 92 community-dwelling adults living with HIV used a new mobile app for symptom self-management and completed the Health-ITUES to assess the usability of the app. They also completed the Post-Study System Usability Questionnaire (PSSUQ), a widely used and well-validated usability assessment tool. Correlations between these scales and each of the subscales were assessed. The subscales of the Health-ITUES showed high internal consistency reliability (Cronbach alpha=.85-.92). Each of the Health-ITUES subscales and the overall scale was moderately to strongly correlated with the PSSUQ scales (r=.46-.70), demonstrating the criterion validity of the Health-ITUES. The Health-ITUES has demonstrated reliability and validity for use in assessing the usability of mHealth technologies in community-dwelling adults living with a chronic illness. ©Rebecca Schnall, Hwayoung Cho, Jianfang Liu. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 05.01.2018.
Ratna Purwaningsih; Ikhsan Yenifi
Website development needs to pay attention to usability aspect which consist of four factors: efficiency, effectiveness, satisfactions and error rate. The website of International Office of Diponegoro University provides academic information for Indonesian students and foreign students. The website still has some problem, especially on searching certain information. This research aims to evaluate the design of the existing website and measures the usability. A well-designed website will help ...
Satwicz, T.; Bharadwaj, A.; Evans, J.; Dirks, J.; Clark Cole, K.
Transforming geological data into information that has broad scientific and societal impact is a process fraught with barriers. Data sets and tools are often reported to have poor user experiences (UX) that make scientific work more challenging than it needs be. While many other technical fields have benefited from ongoing improvements to the UX of their tools (e.g., healthcare and financial services) scientists are faced with using tools that are labor intensive and not intuitive. Our research team has been involved in a multi-year effort to understand and improve the UX of scientific tools and data sets. We use a User-Centered Design (UCD) process that involves naturalistic behavioral observation and other qualitative research methods adopted from Human-Computer Interaction (HCI) and related fields. Behavioral observation involves having users complete common tasks on data sets, tools, and websites to identify usability issues and understand the severity of the issues. We measure how successfully they complete tasks and diagnosis the cause of any failures. Behavioral observation is paired with in-depth interviews where users describe their process for generating results (from initial inquiry to final results). By asking detailed questions we unpack common patterns and challenges scientists experience while working with data. We've found that tools built using the UCD process can have a large impact on scientist work flows and greatly reduce the time it takes to process data before analysis. It is often challenging to understand the organization and nuances of data across scientific fields. By better understanding how scientists work we can create tools that make routine tasks less-labor intensive, data easier to find, and solve common issues with discovering new data sets and engaging in interdisciplinary research. There is a tremendous opportunity for advancing scientific knowledge and helping the public benefit from that work by creating intuitive, interactive
Dwi Susanto, Tony; Ingesti Prasetyo, Anisa; Astuti, Hanim Maria
At this moment, the need for web as an information media is highly important. Not only confined in the infotainment area, government, and education, but health as well uses the web media as a medium for providing information effectively. BloobIS is a web based application which integrates blood supply and distribution information at the Blood Transfusion Unit. Knowing how easy information is on BloobIS is marked by how convenient the website is used. Up until now, the BloobIS website is nearing completion but testing has not yet been performed to users and is on the testing and development phase in the Development Life Cycle software. Thus, an evaluation namely the quality control software which focuses on the perspective of BloobIs web usability is required. Hallway Usability Testing and ISO 9241:11 are the methods chosen to measure the BloobIS application usability. The expected outputs of the quality control software focusing on the usability evaluation are being able to rectify the usability deficiencies on the BloobIs web and provide recommendations to develop the web as a basic BloobIS web quality upgraed which sets a goal to amplify the satisfaction of web users based on usability factors in ISO 9241:11.
This paper studies heuristic usability evaluation of user interfaces. The literature review distinguishes characteristics of augmented reality and smartphones, presents heuristic evaluation, PACMAD usability model, personal navigation assistants, video games, augmented reality and J. Nielsen usability heuristics. In research part, usability heuristics of related subject fields and design guidelines are combined. Created heuristics and control questionnaire are used for evaluation of augmented...
AlOnazi, Amani A.
As processor clock rates become more dynamic and workloads become more adaptive, the vulnerability to global synchronization that already complicates programming for performance in today\\'s petascale environment will be exacerbated. Algebraic multigrid (AMG), the solver of choice in many large-scale PDE-based simulations, scales well in the weak sense, with fixed problem size per node, on tightly coupled systems when loads are well balanced and core performance is reliable. However, its strong scaling to many cores within a node is challenging. Reducing synchronization and increasing concurrency are vital adaptations of AMG to hybrid architectures. Recent communication-reducing improvements to classical additive AMG by Vassilevski and Yang improve concurrency and increase communication-computation overlap, while retaining convergence properties close to those of standard multiplicative AMG, but remain bulk synchronous.We extend the Vassilevski and Yang additive AMG to asynchronous task-based parallelism using a hybrid MPI+OmpSs (from the Barcelona Supercomputer Center) within a node, along with MPI for internode communications. We implement a tiling approach to decompose the grid hierarchy into parallel units within task containers. We compare against the MPI-only BoomerAMG and the Auxiliary-space Maxwell Solver (AMS) in the hypre library for the 3D Laplacian operator and the electromagnetic diffusion, respectively. In time to solution for a full solve an MPI-OmpSs hybrid improves over an all-MPI approach in strong scaling at full core count (32 threads per single Haswell node of the Cray XC40) and maintains this per node advantage as both weak scale to thousands of cores, with MPI between nodes.
MapReduce is a distributed programming framework designed to ease the development of scalable data-intensive applications for large clusters of commodity machines. Most machine learning and data mining applications involve iterative computations over large datasets, such as the Web hyperlink structures and social network graphs. Yet, the MapReduce model does not efficiently support this important class of applications. The architecture of MapReduce, most critically its dataflow techniques and task scheduling, is completely unaware of the nature of iterative applications; tasks are scheduled according to a policy that optimizes the execution for a single iteration which wastes bandwidth, I/O, and CPU cycles when compared with an optimal execution for a consecutive set of iterations. This work presents iHadoop, a modified MapReduce model, and an associated implementation, optimized for iterative computations. The iHadoop model schedules iterations asynchronously. It connects the output of one iteration to the next, allowing both to process their data concurrently. iHadoop\\'s task scheduler exploits inter- iteration data locality by scheduling tasks that exhibit a producer/consumer relation on the same physical machine allowing a fast local data transfer. For those iterative applications that require satisfying certain criteria before termination, iHadoop runs the check concurrently during the execution of the subsequent iteration to further reduce the application\\'s latency. This thesis also describes our implementation of the iHadoop model, and evaluates its performance against Hadoop, the widely used open source implementation of MapReduce. Experiments using different data analysis applications over real-world and synthetic datasets show that iHadoop performs better than Hadoop for iterative algorithms, reducing execution time of iterative applications by 25% on average. Furthermore, integrating iHadoop with HaLoop, a variant Hadoop implementation that caches
Paul, Celeste Lyn
A review of case studies about usability in eight Free/Libre/Open Source Software (FLOSS) projects showed that an important issue regarding a usability initiative in the project was the lack of user research. User research is a key component in the user-centered design (UCD) process and a necessary step for creating usable products. Reasons why FLOSS projects suffered from a lack of user research included poor or unclear project leadership, cultural differences between developer and designers, and a lack of usability engineers. By identifying these critical issues, the FLOSS usability community can begin addressing problems in the efficacy of usability activities and work towards creating more usable FLOSS products.
Full Text Available In this paper, a novel scheme is proposed which comprises the advantages of asynchronous pipelining techniques and the advantages of FPGAs for implementing a 200Mbps MB-OFDM UWB transmitter digital backend modules. In asynchronous pipelined system, registers are used as in synchronous system. But they are controlled by handshaking signals. Since FPGAs are rich in registers, design and implementation of asynchronous pipelined MBOFDM UWB transmitter on FPGA using four-phase bundled-data protocol is considered in this paper. Novel ideas have also been proposed for designing asynchronous OFDM using Modified Radix-24 SDF and asynchronous interleaver using two RAM banks. Implementation has been performed on ALTERA STRATIX II EP2S60F1020C4 FPGA and it is operating at a speed of 350MHz. It is assured that the proposed MB-OFDM UWB system can be made to work on STRATIX III device with the operating frequency of 528MHz in compliance to the ECMA-368 standard. The proposed scheme is also applicable for FPGA from other vendors and ASIC.
Huang, Yuecheng; Cheng, Wuyi; Luo, Sida; Luo, Yun; Ma, Chengchen; He, Tailin
The features of the asynchronous correlation between accident indices and the factors that influence accidents can provide an effective reference for warnings of coal mining accidents. However, what are the features of this correlation? To answer this question, data from the China coal price index and the number of deaths from coal mining accidents were selected as the sample data. The fluctuation modes of the asynchronous correlation between the two data sets were defined according to the asynchronous correlation coefficients, symbolization, and sliding windows. We then built several directed and weighted network models, within which the fluctuation modes and the transformations between modes were represented by nodes and edges. Then, the features of the asynchronous correlation between these two variables could be studied from a perspective of network topology. We found that the correlation between the price index and the accidental deaths was asynchronous and fluctuating. Certain aspects, such as the key fluctuation modes, the subgroups characteristics, the transmission medium, the periodicity and transmission path length in the network, were analyzed by using complex network theory, analytical methods and spectral analysis method. These results provide a scientific reference for generating warnings for coal mining accidents based on economic indices. PMID:27902748
Hagmann, D.B.; Coughlan, J.B.
A large remote vacuum duct joining system has been developed for fusion machines that uses several two-jaw screwdriven clamps. The preferred location for clamp installation is inside the vacuum duct where access space is available for the actuating device. It also decreases space needed for handling operations exterior to the duct. The clamp system is unique in that it is low cost, applies force directly over the seal, permits leak testing to the seal annulus, is highly reliable, can be remotely replaced, and is usable on a variety of other applications
Kitson, Nicole A; Price, Morgan; Bowen, Michael; Lau, Francis
Medication errors are a significant source of actual and potential harm for patients. Community medication records have the potential to reduce medication errors, but they can also introduce unintended consequences when there is low fit to task (low cognitive fit). PharmaNet is a provincially managed electronic repository that contains the records for community-based pharmacy-dispensed medications in British Columbia. This research explores the usability of PharmaNet, as a representative community-based medication repository. We completed usability inspections of PharmaNet through vendor applications. Vendor participants were asked to complete activity-driven scenarios, which highlighted aspects of medication management workflow. Screen recording was later reviewed. Heuristics were applied to explore usability issues and improvement opportunities. Usability inspection was conducted with four PharmaNet applications. Ninety-six usability issues were identified; half of these had potential implications for patient safety. These were primarily related to login and logout procedures; display of patient name; display of medications; update and display of alert information; and the changing or discontinuation of medications. PharmaNet was designed primarily to support medication dispensing and billing activities by community pharmacies, but is also used to support care providers with monitoring and prescribing activities. As such, some of the features do not have a strong fit for other clinical activities. To improve fit, we recommend: having a Current Medications List and Displaying Medication Utilization Charts.
Full Text Available In this research, an E-learning environment is developed for the teacher candidates taking the course on Scientific Research Methods. The course contents were adapted to one of the constructivist approach models referred to as 5E, and an expert opinion was received for the compliance of this model. An usability analysis was also performed to determine the usability of the e-learning environment. The participants of the research comprised 42 teacher candidates. The mixed method was used in the research. 3 different data collection tools were used in order to measure the three basic concepts of usability analyses, which are the dimensions of effectiveness, efficiency and satisfaction. Two of the data collection tools were the scales developed by different researchers and were applied with the approval received from the researchers involved. On the other hand, the usability test as another data tool was prepared by the researchers who conducted this study for the purpose of determining the participants’ success in handling the twelve tasks assigned to them with respect to the use of elearning environment, the seconds they spent on that environment and the number of clicks they performed. Considering the results of the analyses performed within the data obtained, the usability of the developed e-learning environment proved to be at a higher rate.
Nathan, Shelena Soosay; Hussain, Azham; Hashim, Nor Laily; Omar, Mohd Adan
This paper discuss on the dimensions that has been derived for the hearing-impaired mobile applications usability model. General usability model consist of general dimension for evaluating mobile application however requirements for the hearing-impaired are overlooked and often scanted. This led towards mobile application developed for the hearing-impaired are left unused. It is also apparent that these usability models do not consider accessibility dimensions according to the requirement of the special users. This complicates the work of usability practitioners as well as academician that practices research usability when application are developed for the specific user needs. To overcome this issue, dimension chosen for the hearing-impaired are ensured to be align with the real need of the hearing-impaired mobile application. Besides literature studies, requirements for the hearing-impaired mobile application have been identified through interview conducted with hearing-impaired mobile application users that were recorded as video outputs and analyzed using Nvivo. Finally total of 6 out of 15 dimensions gathered are chosen for the proposed model and presented.
Abdul Ghani Aida Affina
Full Text Available With more than 200 number of shopping centre in Klang Valley itself, we the consumer actually have vast of choices. Instead of the machineries varieties from the lower class product till the posh one, each of those shopping centres eventually offers the typical product same as others. Those shopping centers are competing with each other and in great endeavour to attract more consumers, to visit and spend. As for the visitor, the typical product and boring ambience seems similar in all malls, and is looking something beyond the standard. Something that promising quality embedded in shopping centre which evokes the various emotions of the user along their journey in malls. This quality is known as usability. Usability; as defined generally is a global user’s experience response with product, environment, service or facilities. It is an assessment in extracting the qualities of shopping centre design. In mapping it, there are a few synthesizing methods to implement it. Therefore, this paper purposely to review the method that been used in usability of Malaysia’s shopping centre research with a few references on previous research done in usability assessment by predecessor’s scholars. With the accentuation on three elements that anchoring what the usability is: effectiveness, efficient and satisfaction, it is hope that this overview can lead other researcher in portraying its relationship with the quality and ‘user friendly’ design of shopping centre.
Walter, X. A.; Stinchcombe, A.; Greenman, J.; Ieropoulos, I.
This study reports for the first time the full charging of a state-of-the-art mobile smartphone, using Microbial Fuel Cells fed with urine. This was possible by employing a new design of MFC that allowed scaling-up without power density losses. Although it was demonstrated in the past that a basic mobile phone could be charged by MFCs, the present study goes beyond this to show how, simply using urine, charges a modern-day smartphone. Several energy-harvesting systems have been tested and res...
Full Text Available Instead of pursuing traditional testing methods, Discovery and Innovation at Wayne State University Libraries settled on an alternate path to user-centered design when redesigning our library website: running hour-long “guerrilla” usability tests each week for two semesters. The team found immediate successes with this simple, cost-effective method of usability testing, leading to similar redesign projects for other online resources. Emphasizing the importance of iterative design and continuous improvement, this article will detail the authors’ experience conducting short weekly tests, suggestions for institutions looking to begin similar testing programs, and low-stakes testing as a pathway to improved design for the library as a whole. In spring 2016, the Discovery and Innovation web team at Wayne State University Libraries began a redesign of our main library homepage, making the first major updates to the site since 2013. After launching the initial design, we wanted to improve the new website with feedback from real users, following Jakob Nielsen’s decades-old assertion that redesigning websites based on user feedback “can substantially improve usability” (Nielsen, 1993. Instead of using remote and large-scale testing options, we chose a lean, iterative approach, and committed to two semesters of brief, weekly “guerrilla” usability sessions with student users. Not only did this method produce powerful results, but its attainable, iterative approach ultimately led to an increased user focus beyond the library homepage. If you have an hour a week, a laptop, and at least one other colleague willing to help, you can start usability testing, guerrilla-style. Though we found success with this method, using such a stripped-down approach wasn’t immediately obvious. At the beginning of this project, we didn’t know a whole lot about conducting user testing, having relied mostly on survey responses, search logs, and Piwik website
Damek, Nawel; Kamoun, Samira
In this communication, two recursive parametric estimation algorithms are analyzed and applied to an squirrelcage asynchronous machine located at the research ''Unit of Automatic Control'' (UCA) at ENIS. The first algorithm which, use the transfer matrix mathematical model, is based on the gradient principle. The second algorithm, which use the state-space mathematical model, is based on the minimization of the estimation error. These algorithms are applied as a key technique to estimate asynchronous machine with unknown, but constant or timevarying parameters. Stator voltage and current are used as measured data. The proposed recursive parametric estimation algorithms are validated on the experimental data of an asynchronous machine under normal operating condition as full load. The results show that these algorithms can estimate effectively the machine parameters with reliability.
Karandey, V. Yu; Popov, B. K.; Popova, O. B.; Afanasyev, V. L.
In the article, questions and tasks of determination of power and the moment on a shaft of special asynchronous electric drives are considered. Use of special asynchronous electric drives in mechanical engineering and other industries is relevant. The considered types of electric drives possess the improved mass-dimensional indicators in comparison with singleengine systems. Also these types of electric drives have constructive advantages; the improved characteristics allow one to realize the technological process. But creation and design of new electric drives demands adjustment of existing or development of new methods and approaches of calculation of parameters. Determination of power and the moment on a shaft of special asynchronous electric drives is the main objective during design of electric drives. This task has been solved based on a method of electromechanical transformation of energy.
Ma, Philip Y; Fok, Mable P; Shastri, Bhavin J; Wu, Ben; Prucnal, Paul R
We propose and experimentally demonstrate a novel architecture for interfacing and transmitting a Gigabit Ethernet (GbE) signal using asynchronous incoherent optical code division multiple access (OCDMA). This is the first such asynchronous incoherent OCDMA system carrying GbE data being demonstrated to be working among multi-users where each user is operating with an independent clock/data rate and is granted random access to the network. Three major components, the GbE interface, the OCDMA transmitter, and the OCDMA receiver are discussed in detail. The performance of the system is studied and characterized through measuring eye diagrams, bit-error rate and packet loss rate in real-time file transfer. Our Letter also addresses the near-far problem and realizes asynchronous transmission and detection of signal.
Sarah Williams PhD
Full Text Available The Internet is increasingly used as a tool in qualitative research. In particular, asynchronous online focus groups are used when factors such as cost, time, or access to participants can make conducting face-to-face research difficult. In this article we consider key methodological issues involved in using asynchronous online focus groups to explore experiences of health and illness. The written nature of Internet communication, the lack of physical presence, and the asynchronous, longitudinal aspects enable participants who might not normally contribute to research studies to reflect on their personal stories before disclosing them to the researcher. Implications for study design, recruitment strategies, and ethics should be considered when deciding whether to use this method.
Full Text Available In order to demonstrate how learners utilize the text-based asynchronous attributes of the Bulletin Board System, this study explored Japanese-as-a-second-language learners' metalanguage episodes (Swain & Lapkin, 1995, 1998 in offline verbal peer speech and online asynchronous discussions with their Japanese key pals. The findings suggest the crucial role of offline collaborative dialogue, the interactional modes in which the episodes occur, and the unique discourse structure of metalanguage episodes concerning online and offline interactions. A high score on the posttest also suggests the high retention of linguistic knowledge constructed through offline peer dialogue. In the offline mode, the learners were able to collaboratively construct knowledge with peers in the stipulated time, while simultaneously focusing on task content in the online interaction. The retrospective interviews and questionnaires reveal the factors that could affect the benefits of the asynchronous computer-mediated communication medium for language learning.
Full Text Available Excitation-inhibition imbalance in neural networks is widely linked to neurological and neuropsychiatric disorders. However, how genetic factors alter neuronal activity, leading to excitation-inhibition imbalance, remains unclear. Here, using the C. elegans locomotor circuit, we examine how altering neuronal activity for varying time periods affects synaptic release pattern and animal behavior. We show that while short-duration activation of excitatory cholinergic neurons elicits a reversible enhancement of presynaptic strength, persistent activation results to asynchronous and reduced cholinergic drive, inducing imbalance between endogenous excitation and inhibition. We find that the neuronal calcium sensor protein NCS-2 is required for asynchronous cholinergic release in an activity-dependent manner and dampens excitability of inhibitory neurons non-cell autonomously. The function of NCS-2 requires its Ca2+ binding and membrane association domains. These results reveal a synaptic mechanism implicating asynchronous release in regulation of excitation-inhibition balance.
Kasapaki, Evangelia; Sparsø, Jens
are either synchronous or mesochronous. We use asynchronous routers to achieve a simpler, smaller, and more robust, self-timed design. Our design exploits the fact that pipelined asynchronous circuits also behave as ripple FIFOs. Thus, it avoids the need for explicit synchronization FIFOs between the routers......In this paper we explore the use of asynchronous routers in a time-division-multiplexed (TDM) network-on-chip (NOC), Argo, that is being developed for a multi-processor platform for hard real-time systems. TDM inherently requires a common time reference, and existing TDM-based NOC designs...... delays derived from a 65nm CMOS implementation, a worstcase analysis shows that a typical design can tolerate a skew of 1-5 cycles (depending on FIFO depths and NI clock frequency). Simulation results of a 2 x 2 NOC confirm this....
Full Text Available In sensory neural system, external asynchronous stimuli play an important role in perceptual learning, associative memory and map development. However, the organization of structure and dynamics of neural networks induced by external asynchronous stimuli are not well understood. Spike-timing-dependent plasticity (STDP is a typical synaptic plasticity that has been extensively found in the sensory systems and that has received much theoretical attention. This synaptic plasticity is highly sensitive to correlations between pre- and postsynaptic firings. Thus, STDP is expected to play an important role in response to external asynchronous stimuli, which can induce segregative pre- and postsynaptic firings. In this paper, we study the impact of external asynchronous stimuli on the organization of structure and dynamics of neural networks through STDP. We construct a two-dimensional spatial neural network model with local connectivity and sparseness, and use external currents to stimulate alternately on different spatial layers. The adopted external currents imposed alternately on spatial layers can be here regarded as external asynchronous stimuli. Through extensive numerical simulations, we focus on the effects of stimulus number and inter-stimulus timing on synaptic connecting weights and the property of propagation dynamics in the resulting network structure. Interestingly, the resulting feedforward structure induced by stimulus-dependent asynchronous firings and its propagation dynamics reflect both the underlying property of STDP. The results imply a possible important role of STDP in generating feedforward structure and collective propagation activity required for experience-dependent map plasticity in developing in vivo sensory pathways and cortices. The relevance of the results to cue-triggered recall of learned temporal sequences, an important cognitive function, is briefly discussed as well. Furthermore, this finding suggests a potential
Wu, Huayi; You, Lan; Gui, Zhipeng; Gao, Shuang; Li, Zhenqiang; Yu, Jingmin
Geoprocessing service orchestration (GSO) provides a unified and flexible way to implement cross-application, long-lived, and multi-step geoprocessing service workflows by coordinating geoprocessing services collaboratively. Usually, geoprocessing services and geoprocessing service workflows are data and/or computing intensive. The intensity feature may make the execution process of a workflow time-consuming. Since it initials an execution request without blocking other interactions on the client side, an asynchronous mechanism is especially appropriate for GSO workflows. Many critical problems remain to be solved in existing asynchronous patterns for GSO including difficulties in improving performance, status tracking, and clarifying the workflow structure. These problems are a challenge when orchestrating performance efficiency, making statuses instantly available, and constructing clearly structured GSO workflows. A Fully Asynchronous and Status-Tracking (FAST) pattern that adopts asynchronous interactions throughout the whole communication tier of a workflow is proposed for GSO. The proposed FAST pattern includes a mechanism that actively pushes the latest status to clients instantly and economically. An independent proxy was designed to isolate the status tracking logic from the geoprocessing business logic, which assists the formation of a clear GSO workflow structure. A workflow was implemented in the FAST pattern to simulate the flooding process in the Poyang Lake region. Experimental results show that the proposed FAST pattern can efficiently tackle data/computing intensive geoprocessing tasks. The performance of all collaborative partners was improved due to the asynchronous mechanism throughout communication tier. A status-tracking mechanism helps users retrieve the latest running status of a GSO workflow in an efficient and instant way. The clear structure of the GSO workflow lowers the barriers for geospatial domain experts and model designers to
Teka, Degif; Dittrich, Yvonne; Kifle, Mesfin
Usability and user centered design (UCD) are central to software development. In developing countries, the gap between IT development and the local use situation is larger than in western countries. However, usability is neither well addressed in software practice nor at the policy making level...... in Ethiopia. Software practitioners focus on functional requirements, meeting deadlines and budget. The software development industry in Ethiopia is in its early stage. The article aims at understanding usability practices in an Ethiopian software development company. Developers, system analysts, product...... configuration, their experience, cultural knowledge and common sense regarding the users' situation guided the design. Prototypes and fast delivery of working versions helped in getting user feedback even if early user focus proved to be a challenge as communication between developers and users suffered from...
Background: In complex buildings with many types of users it can be difficult to satisfy the numerous, often contradictory requirements. Research in usability mostly focuses on evaluating products or facilities with users, after they were built. This paper is part of a PhD project “Usability...... with various users/stakeholders, using creative boundary objects at workshops. Practical Implications: The research results have relevance to researchers, client organisations, facility managers and architects planning new complex facilities. Research limitations: The proposed model is theoretical and needs...... briefing for hospitals”, where methods for capturing user needs and experiences at hospital facilities are investigated in order to feed into design processes and satisfy the users’ needs and maximise the effectiveness of facilities. Purpose: This paper introduces the concept of usability briefing...
Matraf, Munya Saleh Ba; Hussain, Azham
Evaluation for mobile e-book applications are limited and did not address all the important usability measurements. Hence, this study aimed to identify the characteristics that affect user satisfaction on the usability of mobile e-book applications. Five characteristics that have a significant effect on the user satisfaction of mobile e-book applications have been identified namely readability, effectiveness, accessibility, efficiency, and navigation. A usability evaluation was conducted on three mobile e-book applications namely Adobe Acrobat Reader, Ebook Reader, and Amazon Kindle. 30 students from Universiti Utara Malaysia evaluated the mobile e-book applications and their satisfaction was measured using questionnaire. The outcomes discovered that the five characteristics have a significant positive relationship with user satisfaction. This provides insights into the main characteristics that increase user satisfaction.
Full Text Available This data article provides a data description on article entitled “A framework for improving web accessibility and usability of Open Course Ware sites”  This Data in Brief presents the data obtained from the accessibility and usability evaluation of the UTPL OCW. The data obtained from the framework evaluation consists of the manual evaluation of the standards criteria and the automatic evaluation of the tools Google PageSpeed and Google Analytics. In addition, this article presents the synthetized tables from standards that are used by the framework to evaluate the accessibility and usability of OCW, and the questionnaires required to extract the data. As a result, the article also provides the data required to reproduce the evaluation of other OCW.
Full Text Available The article describes the design of a mobile workplace learning tool for trainers of the International Training Centre of the International Labour Organization. The motivation behind is to provide trainers with a practical tool that will enable them to recall information at the moment of need and continue to learn in context. On this purpose a set of visual augmented reality cards was created, taking into consideration the fundamental mobile learning and usability principles. The nature of the article is empirical as it reports an experiment carried out with trainers which aimed at testing cards usability and learnability. Results show that the integration of both online and offline strategies was perceived as an added value as trainers could choose to retrieve information as they mostly like; finally, it also resulted in high usability scores, an aspect that contributes to their effectiveness at the workplace.
Zahra, Fatima; Hussain, Azham; Mohd, Haslina
The range and availability of mobile applications is expanding rapidly. With the increased processing power available on portable devices, developers are increasing the range of services by embracing smartphones in their extensive and diverse practices. While usability testing and evaluations of mobile applications have not yet touched the accuracy level of other web based applications. The existing usability models do not adequately capture the complexities of interacting with applications on a mobile platform. Therefore, this study aims to presents review on existing usability models for mobile applications. These models are in their infancy but with time and more research they may eventually be adopted. Moreover, different categories of mobile apps (medical, entertainment, education) possess different functional and non-functional requirements thus customized models are required for diverse mobile applications.
Emmanouilidou, Kyriaki; Derri, Vassiliki; Antoniou, Panagiotis; Kyrgiridis, Pavlos
The purpose of the study was to compare the influences of a training programme's instructional delivery method (synchronous and asynchronous) on Greek in-service physical educators' cognitive understanding on student assessment. Forty nine participants were randomly divided into synchronous, asynchronous, and control group. The experimental groups…
Al Dobaikhi, Hend; Woollard, John
The impacts of emerging ICT into educational curricula Asynchronous discussion forumDiscussion groups via e-learning environmentPosting questions and commentsSelf-efficacy in asynchronous e-learning Web community participationCollaborative learning can be fosteredPositive impacts on objectives of educational curriculum
Full Text Available Digital technologies have opened a large set of opportunities for new electronic services (e-commerce, e-health, e-studies etc.. There are many considerations that need to be made when programmers are building new application software or system software. The software needs to be attractive enough that people want to look at it. It also needs to contain all necessary information that developers want to share with their readers (customers, users in order to help them achieve the objective for which they came to their website, use their software, or interact with their teaching packages. The oversupply of e-services products has created a need for usability research and development. “Usability means making products and systems easier to use, and matching them more closely to user needs and requirements”. Usability is a key concept of the human-computer interface and is concerned with making computer systems easy to learn and easy to use through a user-centered design process. The in-depth understanding of usability concepts and processes are critical for large-scale acceptance of new e-services and knowledge productivity. Poorly designed software can be extremely annoying to users. Smith and Mayes state that „usability is now recognised as a vital determining factor in the success of any new computer system or computer-based service”. Studies have shown that the main health problems of computer users are repetitive strain injuries, visual discomfort and stress-related disorders. Beside other risk factors, such as poor workstation design, uncomfortable work postures, long hours of computer use every day, stress, etc., also poor design and usability of the computer systems, as well as computer technical problems, add to the pressure felt by the user, which may in turn cause stress-related disorders.
Jyu, Siao-Shan; Jiang, Guo-Hao; Lai, Yinchieh
Laser dynamics of asynchronous rational harmonic mode-locked (ARHM) fiber soliton lasers are investigated in detail. In particular, based on the unique laser dynamics of asynchronous mode-locking, we have developed a new method for determining the effective active modulation strength in situ for ARHM lasers. By measuring the magnitudes of the slowly oscillating pulse timing position and central frequency, the effective phase modulation strength at the multiplication frequency of rational harmonic mode-locking can be accurately inferred. The method can be a very useful tool for developing ARHM fiber lasers. (paper)
Shevchenko, A. A.; Temlyakova, Z. S.; Grechkin, V. V.; Vilberger, M. E.
The article proposes a method for optimizing the incremental heating calculation in the active volume of a large asynchronous motor for certain kinds of load characteristics. The incremental heating calculation is conditioned by the need to determine the aging level of the insulation and to predict a decrease in the electric machine service life. The method for optimizing the incremental heating calculation of asynchronous motor active volume is based on the automation of calculating the heating when simulating the self-starting process of the motor after eliminating an AC drop.
Romanenko N. G.
Full Text Available the application of virtual laboratories will allow to show different transition processes, as well as to carry out experiments that are very expensive in real electrical machines’ labs, for example, to calculate the energy costs in electric drives. Models of non-regulation asynchronous drive and frequency-regulated asynchronous electric drive are examined in this article. The author has calculated and compared the energy losses of these systems with various types of loads and this lets us to evaluate work processes of many technical devices.
Rissanen, Mikko J; Kume, Naoto; Kuroda, Yoshihiro; Kuroda, Tomohiro; Yoshimura, Koji; Yoshihara, Hiroyuki
Many VR technology based training systems use expert's motion data as the training aid, but would not provide any short-cut to teaching medical skills that do not depend on exact motions. Earlier we presented Annotated Simulation Records (ASRs), which can be used to encapsulate experts' insight on psychomotor skills. Annotations made to behavioural parameters in training simulators enable asynchronous teaching instead of just motion training in a proactive way to the learner. We evaluated ASRs for asynchronous teaching of Digital Rectal Examination (DRE) with 3 urologists and 8 medical students. The ASRs were found more effective than motion-based training with verbal feedback.
Nielsen, Lars Skovby; Sparsø, Jens
This paper describes a number of design issues relating to the implementation of low-power asynchronous signal processing circuits. Specifically, the paper addresses the design of a dedicated processor structure that implements an audio FIR filter bank which is part of an industrial application....... The algorithm requires a fixed number of steps and the moderate speed requirement allows a sequential implementation. The latter, in combination with a huge predominance of numerically small data values in the input data stream, is the key to a low-power asynchronous implementation. Power is minimized in two...
Meza, David; Berndt, Sarah
The purpose of the Sentiment of Search Study for NASA Johnson Space Center (JSC) is to gain insight into the intranet search environment. With an initial usability survey, the authors were able to determine a usability score based on the Systems Usability Scale (SUS). Created in 1986, the freely available, well cited, SUS is commonly used to determine user perceptions of a system (in this case the intranet search environment). As with any improvement initiative, one must first examine and document the current reality of the situation. In this scenario, a method was needed to determine the usability of a search interface in addition to the user's perception on how well the search system was providing results. The use of the SUS provided a mechanism to quickly ascertain information in both areas, by adding one additional open-ended question at the end. The first ten questions allowed us to examine the usability of the system, while the last questions informed us on how the users rated the performance of the search results. The final analysis provides us with a better understanding of the current situation and areas to focus on for improvement. The power of search applications to enhance knowledge transfer is indisputable. The performance impact for any user unable to find needed information undermines project lifecycle, resource and scheduling requirements. Ever-increasing complexity of content and the user interface make usability considerations for the intranet, especially for search, a necessity instead of a 'nice-to-have'. Despite these arguments, intranet usability is largely disregarded due to lack of attention beyond the functionality of the infrastructure (White, 2013). The data collected from users of the JSC search system revealed their overall sentiment by means of the widely-known System Usability Scale. Results of the scores suggest 75%, +/-0.04, of the population rank the search system below average. In terms of a grading scaled, this equated to D or
Nawaz, Ather; Clemmensen, Torkil
As the number of website users in Asia grows, there is an increasing need to gain an overview of human–computer interaction (HCI) research about users and websites in that context. This article presents an overview of HCI research on website usability in Asia “from within,” which outlines...... discusses the results and the need for a greater sensitivity to what is “local” and “from within” in HCI research and what this can add to the existing literature on website usability....
Peeters, J.; Van Dorst, C. [Hyteps, Gemert (Netherlands)
The three phase asynchronous motor has been applied in various installations since time immemorial. Although the motor is more efficient at full mechanical load, this is not always applied efficiently. Can the efficiency of low load motors be improved or is this a utopia? The Sinusoidal Motor Controller (SinuMEC) improves efficiency, saves energy and lengthens the life span. [mk]. [Dutch] De driefasen asynchrone motor wordt sinds mensenheugenis in uiteenlopende installaties toegepast. Hoewel de motor met een volle mechanische belasting efficient is, wordt deze niet altijd efficient toegepast. Kan de efficiency van laag belaste motoren worden verbeterd of is dit een utopie? De Sinusoidal Motor efficiency controller (SinuMEC) verbetert de efficiency, bespaart energie en verlengt de levensduur.
The impact that wireless communications has had for gas and oil producers was discussed. Wireless communication, which has been replacing the traditional formats of radio and telephone data networks, has proved to be cheaper, smaller, and faster than creating privately owned communication networks. With highly developed supervisory control and data acquisition systems - combined with cellular or satellite technology - information from drill sites can be online at the corporate headquarters instantaneously. Eighty percent of Canada's land mass is beyond reach of traditional wireline and wireless services. Research into advanced communications, including telecommunication and mobile applications, yielded lucrative results for service providers such as BCTel, SaskTel, Bell Mobility and AGT. The latest data transmission technology is the cellular digital packet data (CDPD) which will operate over existing cellular networks. However, unlike circuit-switched cellular, CDPD technology provides an airlink where data is secure. It will be available to the marketplace over the course of the coming year. Among other advantages, CDPD will allow producers to remotely monitor production information and downtime alarms from wells and compressor stations. It will also provide fleet operators with the means to monitor operating vital signs on rolling stock
Kushniruk, Andre; Senathirajah, Yalini; Borycki, Elizabeth
The usability and safety of health information systems have become major issues in the design and implementation of useful healthcare IT. In this paper we describe a multi-phased multi-method approach to integrating usability engineering methods into system testing to ensure both usability and safety of healthcare IT upon widespread deployment. The approach involves usability testing followed by clinical simulation (conducted in-situ) and "near-live" recording of user interactions with systems. At key stages in this process, usability problems are identified and rectified forming a usability and technology-induced error "safety net" that catches different types of usability and safety problems prior to releasing systems widely in healthcare settings.
McGillivary, P. A.; Borges de Sousa, J.; Wackowski, S.; Walker, G.
Small remotely piloted aircraft have recently been used for maritime remote sensing, including launch and retrieval operations from land, ships and sea ice. Such aircraft can also function to collect and communicate data from other ocean observing system platforms including moorings, tagged animals, drifters, autonomous surface vessels (ASVs), and autonomous underwater vessels (AUVs). The use of small remotely piloted aircraft (or UASs, unmanned aerial systems) with a combination of these capabilities will be required to monitor the vast areas of the open ocean, as well as in harsh high-latitude ecosystems. Indeed, these aircraft are a key component of planned high latitude maritime domain awareness environmental data collection capabilities, including use of visible, IR and hyperspectral sensors, as well as lidar, meteorological sensors, and interferometric synthetic aperture radars (ISARs). We here first describe at-sea demonstrations of improved reliability and bandwidth of communications from ocean sensors on autonomous underwater vehicles to autonomous surface vessels, and then via remotely piloted aircraft to shore, ships and manned aircraft using Delay and Disruption Tolerant (DTN) communication protocols. DTN enables data exchange in communications-challenged environments, such as remote regions of the ocean including high latitudes where low satellite angles and auroral disturbances can be problematic. DTN provides a network architecture and application interface structured around optionally-reliable asynchronous message forwarding, with limited expectations of end-to-end connectivity and node resources. This communications method enables aircraft and surface vessels to function as data mules to move data between physically disparate nodes. We provide examples of the uses of this communication protocol for environmental data collection and data distribution with a variety of different remotely piloted aircraft in a coastal ocean environment. Next, we
Nawaz, Ather; Skjæret, Nina; Lægdheim Helbostad, Jorunn
Serious games (exergames) have the potential to be effective for postural balance and increasing muscle strength. Several games have been developed to increase physical fitness and balance among older adults. However, it is unclear to which degree usability and acceptability of exergames for olde...
We aimed to assess the level of microbial contamination of re-usable laryngoscope blades at a public hospital in South Africa. Setting. The theatre complex of a secondary-level public hospital in Johannesburg. Methods. Blades from two different theatres were sampled twice daily, using a standardised technique, over a ...
sensitivity, and colour vision data were collected under protocol 2013-073: Automated Target Cueing in Scene Search (Dr. Mackenzie Glaholt, DRDC Toronto... Psychological Science, 1(3), 181- 210. Ryu, Y. S., & Smith-Jackson, T. L. (2006). Reliability and Validity of the Mobile Phone Usability Questionnaire
Hornbæk, K.; Stage, Jan
of the workshop are motivated and an outline of the contents of the papers that were presented in the workshop is given. In addition we summarize some challenges to the interplay between usability evaluation and user interface design agreed upon at the workshop, as well as some solutions that were debated....
Andersen, Malene Hjortboe; Khalid, Md. Saifuddin; Brooks, Eva Irene
of these methods is that they are designed for adults and are not necessarily appropriate to investigations including children. The guiding questions for this systematic literature review are (1) the motivation for conducting usability tests with children, and (2) the kind of methodological, practical, and ethical...
Department of Computer Science, University of Dar-es-Salaam, P.O. Box 35062, Dar-es-Salaam, Tanzania ... in order to assure usability and reduce the incidences and impact of human .... the questions were directed during the DHIS user.
Williams, Sarah C.; Foster, Anita K.
Discovery tools are the next phase of library search systems. Illinois State University's Milner Library implemented EBSCO Discovery Service in August 2010. The authors conducted usability studies on the system in the fall of 2010. The aims of the study were twofold: first, to determine how Milner users set about using the system in order to…
Full Text Available in these types of development projects, the dream of the providing effective access may remain just that – a dream. This paper highlights the important role that usability plays in the drive towards narrowing the digital divide. We report on the outcome of a...
Upitis, Rena; Boese, Karen; Abrami, Philip C.; Anwar, Zaeem
The Digital Resource Exchange About Music (DREAM) is a virtual space for exchanging information about digital learning tools. The purpose of the present study was to determine how users responded to DREAM in the first four months after its public release. This study is the second phase of usability research on DREAM, and was conducted to guide…
Tri, Y.; Erna, A.; Gellysa, U.
Presentation of programs with user interface that can be accessed online through the website of course greatly provide user benefits. User can easily access the program they need. There are usability values that serve as a benchmark for the success of a user accessible program, ie efficiency, effectiveness, and convenience. These usability values also determine the development of the program for the better use. Therefore, on the review title thesis program that will be implemented in STT Dumai was measured usability evaluation. It aims to see which sides are not yet perfect and need to be improved to improve the performance and utilization of the program. Usability evaluation was measured by using smartPLS software. Database used was the result of respondent questionnaires that include questions about the experience when they used program. The result of a review of thesis title program implemented in STT Dumai has an efficiency value of 22.615, the effectiveness of 20.612, and satisfaction of 33.177.
André H. du Plessis
Full Text Available In the development of the metalexicography, the primary focus of metalexicographers was on the development of printed dictionaries. As technology advances, the focus now shifts towards online and electronic products. Tarp (2009:23–24 posits that this shift results in metalexicographic shortcomings. This means that the theories used to create and evaluate dictionaries are not sufficient anymore. Bergenholtz and Bothma (2011:54 show that dictionaries as data carriers are now not only limited to the field of lexicography, but also to information technological fields. For current lexicographers to be successful in the digital age, the theories used in designing, developing and critiquing dictionaries must adapt with regards to current information technological trends, norms and practices. One aspect that must be addressed is the usability of dictionaries and other electronic lexicographic tools. By using usability theories and standards, current metalexicographical principles can be adapted for the digital age in a streamlined fashion. This study aims to show how usability theories and standards can be advantageous for metalexicography and that future electronic metalexicographic endeavours should not be undertaken without considering the usability as part of the theoretical framework.
Full Text Available Various studies have shown that the wine consumption decline in young generation could be influenced by the perception of wine as intimidating and difficult to understand, and by the lack of adaptability of the product’s communication strategy and packaging design to their lifestyle. Information available on the packaging is often complex and confusing for novice wine consumers and sometimes even irrelevant in regards to the intrinsic characteristics of the product. Furthermore, wine is seen by young adult consumers as old fashion, formal and mostly not associated with their relaxed attitude and “on the move” lifestyle. The objective of this paper is to analyse the usability key principles and heuristic and their applicability in wine marketing as a mean to improve the perception and increase understanding of wine for the young and/or novice consumers. The paper aims to review the existing knowledge and findings about the concept of usability (with special emphasis on Usability Engineering and Human Computer Interaction (HCI, in order to explore the aspects applicable in wine marketing. The usability concept proves useful in wine marketing to simplify the decision process, to make the meeting with the product less intimidating and more engaging, and to decrease the risk perception for the inexperienced wine consumers.
Razak, Mohd Nur Faiz Abd; Hussain, Azham; Hamdi, Mohd Maizan Fishol
Nowadays, YouTube is the 3rd most visited website in the world. It was created for users to search, watch and share video. Statistics show that YouTube run in more than 88 countries and support 76 different languages which covered almost 95% of Internet population globally. Therefore, a usability study is for specific type of users such as based on gender, range of age and country is considered a must for this kind of top website. In this study, we focus on YouTube website usability for Malaysian teenagers that are currently schooling in boarding school with limited access of Internet. It was done in a controlled lab environment with proper devices and software as MacBook, LCD Monitor, and WhatPulse heat map tracker. The evaluation was made based on usability metrics: ease of use, usefulness and satisfaction of users with combination of recording videos, mouse and keyboard heat map and questionnaires. Findings show that most of the respondents just use YouTube for video watching only while ignoring other features in the same time. There are difficulties in using it at the first moment but could catch up in short time. It shows how usable YouTube website especially in the learnability and memorability aspects.
Girard, Tulay; Pinar, Musa
This research advances the understanding of the usability of marketing case study modules in the area of interactive web-based technologies through the assignment of seven interactive case modules in a Principles of Marketing course. The case modules were provided for marketing students by the publisher, McGraw Hill Irwin, of the…
Usability evaluation methods (UEMs) are widely recognised as an essential part of systems development. Assessments of the performance of UEMs, however, have been criticised for low validity and limited reliability. The present study extends this critique by describing seven dogmas in recent work ...... research approaches that may help move beyond the dogmas. In particular, we emphasise detailed studies of evaluation processes, assessments of the impact of UEMs on design carried out in real-world systems development and analyses of how UEMs may be combined......Usability evaluation methods (UEMs) are widely recognised as an essential part of systems development. Assessments of the performance of UEMs, however, have been criticised for low validity and limited reliability. The present study extends this critique by describing seven dogmas in recent work...... on UEMs. The dogmas include using inadequate procedures and measures for assessment, focusing on win-lose outcomes, holding simplistic models of how usability evaluators work, concentrating on evaluation rather than on design and working from the assumption that usability problems are real. We discuss...
Lautenbach, M.A.E.; Schegget, I.E. ter; Schoute, A.E.; Witteman, C.L.M.
An evaluation of the Utrecht University website was carried out with 240 students. New criteria were drawn from the literature and operationalized for the study. These criteria are surveyability and findability. Web pages can be said to satisfy a usability criterion if their efficiency and
Thiruvenkadam, G.; Brombacher, A.C.; Lu, Y.; Ouden, den P.H.
In this paper we report the findings of a study intended to assess the usability of consumer related information sources in order to improve the design processes of innovative electronic products. Specifically, an evaluation is done of the quality and content of information that would help product
Sørensen, Morten; Franek, Ondrej; Christensen, Søren K.; Pedersen, Gert Frølund; Ebert, Hans
The workbench Faraday Cage method (WBFC) is a time efficient module pre-compliance test regarding radiated emission. This work investigates the method’s usability and credibility and concludes that for this particular case the WBFC perform a tolerable compliance test for frequencies below 360 MHz while it is essentially useless for higher frequencies.
As the popularity of online banking Websites has increased, the security of these sites has become increasingly critical as attacks against these sites are on the rise. However, the design decisions made during construction of the sites could make usability more difficult, where the user has difficulty making good security decisions. This study…
Liu, Min; Traphagan, Tomoko; Huh, Jin; Koh, Young Ihn; Choi, Gilok; McGregor, Allison
The purpose of this paper is to report on a usability study for ESL websites conducted to gain insights from learners of English as a second language (ESL) as they interacted with specific sites. Five carefully selected ESL sites were tested by 10 different users generating a total of fifty testing sessions. Two major research questions guided the…
Meng, Liqiu; Winter, Stephan; Popovich, Vasily
This book reports the newest research and technical achievements on the following theme blocks: Design of mobile map services and its constraints; Typology and usability of mobile map services; Visualization solutions on small displays for time-critical tasks; Mobile map users; Interaction and adaptation in mobile environments; and Applications of map-based mobile services.
Zhang, Tao; Maron, Deborah J.; Charles, Christopher C.
This article reports results from an empirical usability evaluation of Human-Animal Bond Research Initiative Central as part of the effort to develop an open access research repository and collaboration platform for human-animal bond researchers. By repurposing and altering key features of the original HUBzero system, Human-Animal Bond Research…
Møller, Margrethe Hansen
Based on experience from the research project “User Manuals for Older Adults”, this paper discusses whether there are special ethical concerns with older adults as test persons in a usability test involving the think-aloud method. In this context, older adults are defined as individuals with normal...
Full Text Available The Digital Doorway (DD) is a non-standard computer system deployed to promote computer literacy amongst underprivileged communities in South Africa. Since its inception there has been no usability evaluation of the software installed on the DD...
Sørensen, Morten; Franek, Ondrej; Christensen, Søren K.
The workbench Faraday Cage method (WBFC) is a time efficient module pre-compliance test regarding radiated emission. This work investigates the method’s usability and credibility and concludes that for this particular case the WBFC perform a tolerable compliance test for frequencies below 360 MHz...
Briesch, Amy M.; Briesch, Jacquelyn M.; Chafouleas, Sandra M.
Although teachers are often asked to implement classroom interventions to address student behavior, little is known about their perceived usability of many evidence-based strategies. One thousand five elementary schoolteachers completed the Usage Rating Profile-Intervention-Revised (URP-IR) with regard to the use of one of five evidence-based…
Discusses the need for an intuitive library information gateway to meet users' information needs and describes the process involved in redesigning a library Web site based on experiences at Roger Williams University. Explains usability testing methods that were used to discover how users were interacting with the Web site interface. (Author/LRW)
Ana Castillo-Díaz, Ph. D.
Full Text Available In an increasingly competitive environment in which Internet occupies a prominent place, transferring a brand from the offline to the online environment has become a vital issue for companies. Usability and accessibility have become crucial to enable adequate online brand communication. Ensuring websites are usable and accessible will facilitate web navigation, will improve the company’s image, and will favour loyalty towards the brand.This article presents the results of an investigation measuring the extent to what small and medium enterprises (SMEs employ usability and accessibility as supporting pillars of brand in the online environment to communicate with their audiences. The results indicate that usability is in fact taken into account by SMEs, but it is seen more as a technological element than as a promotion tool for the brand. Accessibility, on the other hand, is of secondary concern in the design of websites analysed, since they are not certified by any standard and are not fully accessible. Thus, it can be argued that the concern to transmit the brand online is incipient but, currently, SMEs do not take advantage of all the potential offered by the Web.
Salter, Susan; Douglas, Tracy; Kember, David
Two mechanisms for engaging in critical reflective dialogue are discussed and compared: face-to-face meetings and asynchronous online discussion. The context is an umbrella action research project, with over 20 participants, which aimed to improve practices in online teaching and contribute to the development of graduate attributes. The article…
Full Text Available Attacking time-sensitive targets has rigid demands for the timeliness and reliability of information transmission, while typical Media Access Control (MAC designed for this application works well only in very light-load scenarios; as a consequence, the performances of system throughput and channel utilization are degraded. For this problem, a feedback-retransmission based asynchronous FRequency hopping Media Access (FRMA control protocol is proposed. Burst communication, asynchronous Frequency Hopping (FH, channel coding, and feedback retransmission are utilized in FRMA. With the mechanism of asynchronous FH, immediate packet transmission and multi-packet reception can be realized, and thus the timeliness is improved. Furthermore, reliability can be achieved via channel coding and feedback retransmission. With theories of queuing theory, Markov model, packets collision model, and discrete Laplace transformation, the formulas of packet success probability, system throughput, average packet end-to-end delay, and delay distribution are obtained. The approximation accuracy of theoretical derivation is verified by experimental results. Within a light-load network, the proposed FRMA has the ability of millisecond delay and 99% reliability as well as outperforms the non-feedback-retransmission based asynchronous frequency hopping media access control protocol. Keywords: Ad hoc networks, Aeronautical communications, Frequency hopping, Media Access Control (MAC, Time-sensitive
Processing large graphs is becoming increasingly important for many domains such as social networks, bioinformatics, etc. Unfortunately, many algorithms and implementations do not scale with increasing graph sizes. As a result, researchers have attempted to meet the growing data demands using parallel and external memory techniques. We present a novel asynchronous approach to compute Breadth-First-Search (BFS), Single-Source-Shortest-Paths, and Connected Components for large graphs in shared memory. Our highly parallel asynchronous approach hides data latency due to both poor locality and delays in the underlying graph data storage. We present an experimental study applying our technique to both In-Memory and Semi-External Memory graphs utilizing multi-core processors and solid-state memory devices. Our experiments using synthetic and real-world datasets show that our asynchronous approach is able to overcome data latencies and provide significant speedup over alternative approaches. For example, on billion vertex graphs our asynchronous BFS scales up to 14x on 16-cores. © 2010 IEEE.
Full Text Available This article presents an embedded multilane traffic data acquisition system based on an asynchronous temporal contrast vision sensor, and algorithms for vehicle speed estimation developed to make efficient use of the asynchronous high-precision timing information delivered by this sensor. The vision sensor features high temporal resolution with a latency of less than 100 ÃŽÂ¼s, wide dynamic range of 120 dB of illumination, and zero-redundancy, asynchronous data output. For data collection, processing and interfacing, a low-cost digital signal processor is used. The speed of the detected vehicles is calculated from the vision sensor's asynchronous temporal contrast event data. We present three different algorithms for velocity estimation and evaluate their accuracy by means of calibrated reference measurements. The error of the speed estimation of all algorithms is near zero mean and has a standard deviation better than 3% for both traffic flow directions. The results and the accuracy limitations as well as the combined use of the algorithms in the system are discussed.
Xie, Kui; Huang, Kun
Epistemic and learning beliefs were found to affect college students' cognitive engagement and study strategies, as well as motivation in classroom settings. However, the relationships between epistemic and learning beliefs, motivation, learning perception, and students' actual learning participation in asynchronous online settings have been…