432 research outputs found
Interaction Between Ion Beams and Plasmas
Interaction between low energy cesium ion beam and thermal cesium plasm
Interaction Between Ion Beams and Plasmas
Stability limits for ion acoustic waves due to interaction between low energy cesium ion beam and thermal cesium plasm
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Investigating the Intelligibility of a Computer Vision System for Blind Users
Computer vision systems to help blind usersare becoming increasingly common yet often these systems are not intelligible. Our work investigates the intelligibility of a wearable computer vision system to help blind users locate and identify people in their vicinity. Providing a continuous stream of information, this system allows us to explore intelligibility through interaction and instructions, going beyond studies of intelligibility that focus on explaining a decision a computer vision system might make. In a study with 13 blind users, we explored whether varying instructions (either basic or enhanced) about how the system worked would change blind users’ experience of the system. We found offering a more detailed set of instructions did not affect how successful users were using the system nor their perceived workload. We did, however, find evidence of significant differences in what they knew about the system, and they employed different, and potentially more effective, use strategies. Our findings have important implications for researchers and designers of computer vision systemsfor blind users, as well more general implications for understanding what it means to make interactive computer vision systems intelligible
Ion beam plume and efflux characterization flight experiment study
A flight experiment and flight experiment package for a shuttle-borne flight test of an 8-cm mercury ion thruster was designed to obtain charged particle and neutral particle material transport data that cannot be obtained in conventional ground based laboratory testing facilities. By the use of both ground and space testing of ion thrusters, the flight worthiness of these ion thrusters, for other spacecraft applications, may be demonstrated. The flight experiment definition for the ion thruster initially defined a broadly ranging series of flight experiments and flight test sensors. From this larger test series and sensor list, an initial flight test configuration was selected with measurements in charged particle material transport, condensible neutral material transport, thruster internal erosion, ion beam neutralization, and ion thrust beam/space plasma electrical equilibration. These measurement areas may all be examined for a seven day shuttle sortie mission and for available test time in the 50 - 100 hour period
At least some errors are randomly generated (Freud was wrong)
An experiment was carried out to expose something about human error generating mechanisms. In the context of the experiment, an error was made when a subject pressed the wrong key on a computer keyboard or pressed no key at all in the time allotted. These might be considered, respectively, errors of substitution and errors of omission. Each of seven subjects saw a sequence of three digital numbers, made an easily learned binary judgement about each, and was to press the appropriate one of two keys. Each session consisted of 1,000 presentations of randomly permuted, fixed numbers broken into 10 blocks of 100. One of two keys should have been pressed within one second of the onset of each stimulus. These data were subjected to statistical analyses in order to probe the nature of the error generating mechanisms. Goodness of fit tests for a Poisson distribution for the number of errors per 50 trial interval and for an exponential distribution of the length of the intervals between errors were carried out. There is evidence for an endogenous mechanism that may best be described as a random error generator. Furthermore, an item analysis of the number of errors produced per stimulus suggests the existence of a second mechanism operating on task driven factors producing exogenous errors. Some errors, at least, are the result of constant probability generating mechanisms with error rate idiosyncratically determined for each subject
The Challenges of Using an Existing Cross-Device Interaction Prototype for Supporting Actual Curation Practices
Volunteer-driven organisations curating historic documents, such as societies and charities, often work within a bring-your-own-device (BYOD) practice and their meetings are in varying situations. A recurring challenge is finding lightweight ways to enable them to share and collectively work with documents using their own devices while in situ. We are working on building novel interaction techniques and applications (prototyped with a custom developer toolkit) for supporting the curation of digital collections – for example, historic documents. We discuss the pros and cons of using an existing prototype system for this purpose and points to consider when taking a prototype from the lab into the wild
User interaction for visual lifelog retrieval in a virtual environment
Efficient retrieval of lifelog information is an ongoing area of research due to the multifaceted nature, and ever increasing size of lifelog datasets. Previous studies have examined lifelog exploration on conventional hardware platforms, but in this paper we describe a novel approach to lifelog retrieval using virtual reality. The focus of this research is to identify what aspects of lifelog retrieval can be effectively translated from a conventional to a virtual environment and if it provides any benefit to the user. The most widely available lifelog datasets for research are primarily image-based and focus on continuous capture from a first-person perspective. These large image corpora are often enhanced by image processing techniques and various other metadata. Despite the rapidly maturing nature of virtual reality as a platform, there has been very little investigation into user interaction within the context of lifelogging. The experiment outlined in this work seeks to evaluate four different virtual reality user interaction approaches to lifelog retrieval. The prototype system used in this experiment also competed at the Lifelog Search Challenge at ACM ICMR 2018 where it ranked first place
HCI 2020: Looking Back to the Future
In March, 2007, a forum entitled HCI 2020: Human Values in a Digital Age, was held in Sanlúcar la Mayor, Spain, just outside Seville. Its purpose was to gather luminaries in computing, design, social sciences, and scientific philosophy to discuss, debate and help formulate an agenda for human-computer interaction (HCI) over the next decade and beyond. This resulted in a detailed report, released in April 2008, in the form of a book called Being Human: Human-Computer Interaction in the Year 20201, authored by 45 members of the wider HCI community. In this panel, we shall build from four core questions. How successfully did the HCI 2020 forum and report recognize trends and shape HCI? What major trends or issues did they fail to anticipate? How valuable to the HCI community, to the participants, and to the sponsoring organizations was the forum and the report? And finally, what does this history suggest about both the process and the ultimate value to HCI, to computing in general, and to the world, of creating a HCI 2035 vison?
Speculative devices for photo display
In this paper, we describe three purposefully provocative, digital photo display technologies designed for home settings. The three devices have been built to provoke questions around how digital photographs might be seen and interacted with in novel ways. They are also intended for speculation about the expressive resources afforded by digital technologies for displaying photos. It is hoped interactions with the devices will help researchers and designers reflect on new design possibilities. The devices are also being deployed as part of ongoing home-oriented field research
Serious Games Application for Memory Training Using Egocentric Images
Mild cognitive impairment is the early stage of several neurodegenerative
diseases, such as Alzheimer's. In this work, we address the use of lifelogging
as a tool to obtain pictures from a patient's daily life from an egocentric
point of view. We propose to use them in combination with serious games as a
way to provide a non-pharmacological treatment to improve their quality of
life. To do so, we introduce a novel computer vision technique that classifies
rich and non rich egocentric images and uses them in serious games. We present
results over a dataset composed by 10,997 images, recorded by 7 different
users, achieving 79% of F1-score. Our model presents the first method used for
automatic egocentric images selection applicable to serious games.Comment: 11 page
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