
Ravi KuberUniversity of Maryland, Baltimore County | UMBC · Department of Information Systems
Ravi Kuber
BSc, MSc, Ph.D.
About
101
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Introduction
Additional affiliations
July 2014 - present
August 2008 - June 2014
Publications
Publications (101)
Mobile device use is omnipresent in everyday life spawning design to account for the increased complexity and diversity of “Situationally Induced Impairments and Disabilities (SIID)”. Although SIIDs frequently impact interactions, little research has attempted to provide generalizable guidance supporting users when these events occur. Situational i...
Prior work suggests that older adults are less aware of potential digital privacy risks compared to younger groups. We seek to expand on these findings by using drawmetrics with 20 older adults (60+) to visualize their experiences with digital privacy via drawing sessions. We further compared older adults with 20 adults of working age (18-59) with...
A special strain of situational impairment, termed “Severely Constraining Situational Impairments” (SCSI), was explored from a novel qualitative perspective. When a severely impairing event presents, the multitude and complexity of ambient agents are often overwhelming, leading to the inability to devise a solution. To classify and help design for...
Deaf and hard of hearing English language learners encounter a range of challenges when learning spoken/written English, many of which are not faced by their hearing counterparts. In this paper, we examine the feasibility of utilizing physiological data, including arousal and eye gaze behaviors, as a method of identifying instances of anxiety and f...
Password managers (PMs) are considered highly effective tools for increasing security, and a recent study by Pearman et al. (SOUPS'19) highlighted the motivations and barriers to adopting PMs. We expand these findings by replicating Pearman et al.'s protocol and interview instrument applied to a sample of strictly older adults (>60 years of age), a...
Personal Identification Numbers (PINs) are widely used as an access control mechanism for digital assets (e.g., smartphones), financial assets (e.g., ATM cards), and physical assets (e.g., locks for garage doors or homes). Using semi-structured interviews (n=35), participants reported on PIN usage for different types of assets, including how users...
Voice-activated personal assistants (VAPAs) are becoming smaller, cheaper, and more accurate, such that they are now prevalent in homes (e.g., Amazon Echo, Sonos One) and on mobile devices (e.g., Google Assistant, Apple Siri) around the world. VAPAs offer considerable potential to individuals who are blind, offering efficiencies over gesture-based...
Situationally-induced impairments and disabilities (SIIDs) are experienced by a range of users. Firefighters can be impacted when performing tasks under the inhospitable conditions often present at the scene of a fire (e.g. thick smoke and loud noise). In this paper, we describe the steps of an approach to support situational awareness (SA) among f...
We report on a qualitative inquiry among security-expert and non-expert mobile device users about the adoption of biometric authentication using semi-structured interviews(n=38, 19/19 expert/non-expert). Security experts more readily adopted biometrics than non-experts but also harbored greater distrust towards its use for sensitive transactions,fe...
We conducted a study of n = 20 older adults to better understand their mental models for what the term 'privacy' means to them in both digital and non-digital contexts. Participants were asked to diagrammatically represent this information and describe their drawings in a semi-structured interview setting. Preliminary coding analysis revealed parti...
This research investigates the variety and complexity of situational impairment events (SIE) that are being experienced by users of smartphone technology of all abilities. The authors have created a classification system to help describe the different types of SIE as well as differentiate a certain subgroup of events that were identified as severel...
We analyze the claims that video recreations of shoulder surfing attacks offer a suitable alternative and a baseline, as compared to evaluation in a live setting. We recreated a subset of the factors of a prior video-simulation experiment conducted by Aviv et al. (ACSAC 2017), and model the same scenario using live participants (n = 36) instead (i....
Voice-activated personal assistants (VAPAs)--like Amazon Echo or Apple Siri--offer considerable promise to individuals who are blind due to widespread adoption of these non-visual interaction platforms. However, studies have yet to focus on the ways in which these technologies are used by individuals who are blind, along with whether barriers are e...
We analyze the claims that video recreations of shoulder surfing attacks offer a suitable alternative and a baseline, as compared to evaluation in a live setting. We recreated a subset of the factors of a prior video-simulation experiment conducted by Aviv et al. (ACSAC 2017), and model the same scenario using live participants ($n=36$) instead (i....
Mobile device users avoiding observational attacks and coping with situational impairments may employ techniques for eyes-free mobile unlock authentication, where a user enters his/her passcode without looking at the device. This study supplies an initial description of user accuracy in performing this authentication behavior with PIN and pattern p...
Mobile device users avoiding observational attacks and coping with situational impairments may employ techniques for eyes-free mobile unlock authentication, where a user enters his/her passcode without looking at the device. This study supplies an initial description of user accu- racy in performing this authentication behavior with PIN and pattern...
A subset of "Situationally Induced Impairments and Disabilities" (SIID), termed "Severely Constraining Situational Impairments" (SCSI), was explored at the user task and motivational level, to better understand the challenges faced by users attempting to perform tasks using a mobile device. Through structured interviews, participants were found to...
Biometric authentication offers promise for mobile security, but its adoption can be controversial, both from a usability and security perspective. We describe a preliminary study, comparing recollections of biometric adoption by computer security experts and non-experts collected in semi-structured interviews. Initial decisions and thought process...
The purpose of this study is to better understand, from an explorative qualitative perspective, the motivations and practices of highly security-conscious users of mobile authentication, and their underlying mental models of those behaviours. Mobile authentication studies have largely overlooked the mindset of these users in the upper bound of secu...
In this study, we examine the ways in which user attitudes towards privacy and security relating to mobile devices and the data stored thereon may impact the strength of unlock authentication, focusing on Android's graphical unlock patterns. We conducted an online study with Amazon Mechanical Turk ($N=750$) using self-reported unlock authentication...
Android unlock patterns are likely the most prevalent graphical password system to date. However, human-chosen authentication stimuli (such as text passwords and PINs) are easy to guess. Does increasing the grid size from 3 × 3 to 4 × 4 help the situation? Yes and no.
This paper describes an exploratory study examining the feasibility of using Brain-Computer Interface (BCI) and gestural technologies to support individuals who are blind during the authentication process. Four legally-blind participants were asked to don the Emotiv Epoc headset, and authenticate entry using gestural cues, emotional cues and mental...
In this paper, we describe an approach to develop alerts for individuals experiencing situationally-induced impairments and disabilities (SIIDs) in inhospitable environments, with a view to support situational awareness and decision making. Our research focuses on the needs of firefighters whose visual and auditory channels may be restricted while...
This paper describes the design of a graduate level course focusing on developing interfaces for purposes of rehabilitation, catering to students from multiple disciplines. Students work on projects relating to the needs of individuals with disabilities, under the supervision of internal and external mentors. The course has been designed to help st...
This paper describes an exploratory study focusing on the methods of mobile authentication currently utilized by individuals who are blind. Perceptions of security are discussed, along with the trade-offs with usability and accessibility. A tactile aid for a mobile authentication interface was introduced to participants to obtain preliminary feedba...
Accelerometer-based commercial activity trackers are a low-cost and convenient method for monitoring and assessing health measures such as gait. However, the accuracy of these activity trackers in slow walking conditions on a minute-by-minute basis is largely unknown. In this study, the accuracy of a hip-worn commercial activity tracker (FitBit Ult...
Given the nature of mobile devices and unlock procedures, unlock authentication is a prime target for credential leaking via shoulder surfing, a form of an observation attack. While the research community has investigated solutions to minimize or prevent the threat of shoulder surfing, our understanding of how the attack performs on current systems...
Given the nature of mobile devices and unlock procedures, unlock authentication is a prime target for credential leaking via shoulder surfing, a form of an observation attack. While the research community has investigated solutions to minimize or prevent the threat of shoulder surfing, our understanding of how the attack performs on current systems...
This paper describes an exploratory study which examined the use of Brain-Computer Interface (BCI) and gestural technologies generated from a BCI headset as a novel potential alternative to a 4-digit PIN code for authentication. Unlike other input modalities, many of these tokens (i.e. “push”, “lift”, “excitement”), can overcome some of the securit...
In this paper, we describe the design and evaluation of a head-mounted tactile prototype and multi-parameter coding scheme to support situational awareness among users. The head has been selected as the location for the interaction because it has been relatively under-researched compared to the torso or hands, and offers potential for hands-free at...
Medication management can often be a challenging task for individuals adhering to a strict regimen. In response, a number of technologies have been developed to remind the user when to take medication and to record how often medications have been consumed. Many of these technologies have not been designed with visually impaired users in mind, makin...
In this paper, we describe a novel approach to measure the susceptibility of smartphone unlock authentication to shoulder surfing attacks. In our methodology, participants play the role of attackers, viewing video-recorded footage of PIN and graphical password pattern authentication input with various camera angles, hand positions, phone sizes, and...
In this paper, we describe a study designed to examine the effects of modality, target size and other design features on task performance. The study has specifically focused on older adults when accessing a mobile interface. Twelve participants (aged 55-89) conducted a set of pointing and steering tasks. Targets 32px in size were found to be most e...
This study explores situationally induced impairments and disabilities (SIIDs) from a unique perspective. A two-week diary study of mobile technology users was conducted to create a corpus of situational impairment events (SIEs) that mobile device users may experience in the wild. As a result, themes and classifications describing the type of SIEs...
Accelerometers have shown great promise and popularity for monitoring gait. However, the accuracy of accelerometers for gait analysis in slow walking conditions is largely unknown. In this study, we compared the accuracy of three accelerometers recommended for gait analysis – Axivity AX3, APDM Opal, and the Actigraph wGT3X-BT, by holding the step-c...
Limb repositioning is necessary for individuals with severe physical disabilities to sustain muscle strength and prevent pressure sores. As robotic technologies become ubiquitous, these tools offer promise to support the repositioning process. However, research has yet to focus on ways in which individuals with severe physical disabilities can cont...
As users become increasingly more reliant on online resources to satisfy their information needs, care is needed to ensure that these resources are credible in nature, especially if a decision is to be taken based upon the information accessed. The credibility of a web site is known to be heavily influenced by its visual appearance. However, for in...
When faced with the threat of observational attacks, mobile device users may attempt to mask the graphical interface to authenticate entry, to reduce the likelihood of third parties viewing and recreating the authentication sequence. However, interacting non-visually with a mobile interface is not without its own challenges. In this paper, we descr...
Authentication on mobile devices is a research priority for the development of usable and trustworthy platforms. However, users may struggle to understand how to balance security and usability for the broad range of important data-driven social and financial transactions on their devices. This concern is especially prevalent in security information...
In this paper, we describe a study specifically focusing on the situationally-induced impairments and disabilities (SIIDs) which individuals who are blind encounter when interacting with mobile devices. We conducted semi-structured interviews with eight legally-blind participants, and presented them with three scenarios to inspire discussion relati...
Android's graphical authentication mechanism requires users to unlock their devices by "drawing" a pattern that connects a sequence of contact points arranged in a 3x3 grid. Prior studies demonstrated that human-generated 3x3 patterns are weak (CCS'13); large portions can be trivially guessed with sufficient training. An obvious solution would be t...
This paper describes a study examining the usability of OnScreenDualScribe (OSDS), a tool to support individuals with physical disabilities with text entry and cursor movement. A portable numeric keypad is used to interact with the OSDS, which can either be held by the user, or can be affixed to a surface for interaction. A study to determine the f...
While screen reading technologies offer considerable promise to individuals who are blind by providing an accessible overview of web-based content, difficulties can be faced determining the credibility of sites and their respective contents. This can impact the user's behavior, particularly if sensitive information needs to be entered (e.g. into a...
In this paper, the authors describe a novel design alternative to the traditional PIN-based user authentication process, through the selection of a sequence of abstract sounds. The authors conducted two studies as part of the research. The frst study examines a user's ability to discriminate between sounds based on the manipulation of various sound...
In this paper, we describe the development of a novel, low-cost, compact sensor/actuator that can be integrated with a commercially-available haptic device, such as the Geomagic Touch, to provide additional capability when grasping virtual objects. The focus of this paper is to investigate the impact of modality on a 'picking and placing' task usin...
In this paper, we describe a participatory-based approach to developing tactile feedback for a head-mounted device. Three focus groups iteratively designed and evaluated tactile interaction concepts for user-generated use-case scenarios. Results showed productive design insights from the groups regarding approaches to tactile coding schemes address...
In this paper, we describe a novel approach to support the traditional PIN-based user authentication process, through the selection of a sequence of abstract sounds. We conducted two studies as part of the research. The first study examined the user’s ability to discriminate between sounds. Results highlighted the benefits of timbre as a differenti...
In this article, we describe an extension to a web browsing tool, designed to support individuals who are blind. The user is able to explore web-based content using the Geomagic Touch device. Both haptic and speech-based cues are presented when alighting over objects (e.g. images, hyperlinks, buttons and textboxes/textareas), replacing much of the...
The process of checking mobile notifications can be challenging when the user is engaged with another task that requires him/her to monitor the path ahead (e.g. running, driving). Developing expressive tactile feedback to communicate key components of the message would enable users to decide whether to attend to the notification, or to continue wit...
In this paper, we describe an approach with the aim of supporting individuals engaged with a task where the eyes are occupied to monitor obstacles within their wider environment. A head-mounted interface has been developed where tactile feedback can be presented to alert the user to important situational events, such as the presence of spatial obst...
This paper describes two studies that examine the ways in which parameters of touch can be manipulated to support human–mobile
interaction, providing designers with greater awareness regarding the range of tactile icons (tactons) for integration with
interfaces. The first study examined the efficacy of presenting tactons via low-cost eccentric rota...
Although it is well known that interaction with a mobile device can be impacted when the environment is inhospitable or when the user is on the move, situationally-induced impairments and disabilities (SIIDs) are often overlooked in the mobile interface design process. In this paper, we describe one step toward supporting mobile users with SIIDs, t...
In this paper, we describe an exploratory study to determine the feasibility of using a low-cost gestural headset to support communication. Findings have shown tasks involving facial gestures, such as blinks and smiles, can be performed and detected by an Augmented and Alternative Communication (AAC) system within a shorter period of time compared...
This paper describes a data gathering study, examining the experiences and day-to-day challenges faced by blind web interface developers when designing sites and online applications. Findings have revealed that considerable amounts of time and cognitive effort can be spent checking code in text editing software and examining the content presented v...
Difficulties are often associated with perceiving tactile feedback from a mobile device while ambulatory. In this paper, we describe a study conducted using multi-parameter tactile icons (tactons) with a view to identifying designs to better resist the masking effects associated with walking. Our findings suggest that tactons encoded with longer du...
This paper describes a Science-Technology-Engineering-Mathematics (STEM) outreach workshop conducted with post-secondary students diagnosed with learning differences, including Learning Disabilities (LD), Attention Deficit / Hyperactivity Disorders (AD/HD), and/or Autism Spectrum Disorders (ASD). In this workshop, students were actively involved in...
In this paper, we describe a first step towards the development of a solution to support the movement and repositioning of an individual's limbs. Limb repositioning is particularly valuable for individuals with physical disabilities who are either bed or chair-bound, to help reduce the occurrence of contractures and pressure ulcers. A data gatherin...
For some individuals with executive function deficits, difficulties may be experienced when executing step-by-step procedures involving cognitive and motor skills. In this paper, we describe the design of a mobile application prototype, developed using a participatory-based approach, in order to enable individuals with executive function deficits t...
As mobile interfaces are often designed with sighted users in mind, difficulties can be experienced by individuals who are blind, when using a mobile screen reader to access content. In this paper, we describe a data gathering study to determine the day-to-day challenges experienced when performing tasks using mobile screen readers. Challenges can...
Authentication mechanisms are often developed without taking into account the needs of users with visual disabilities. In this paper, we describe an extension to an existing tactile authentication system, with the aim of supporting non-visual interaction. Tactile icons are presented in a timed sequence at one fixed point on the interface, reducing...
Interpersonal communication benefits greatly from the emotional information encoded by facial expression, body language, and tone of voice. However, these cues are often lost when sending text-based instant messages. This paper describes a novel approach utilizing gestural and Brain Computer Interface (BCI) input to replace the missing emotional cu...
Haptic technologies are often used to improve access to the structural content of graphical user interfaces, thereby augmenting the interaction process for blind users. While haptic design guidelines offer valuable assistance when developing non-visual interfaces, the recommendations presented are often tailored to the feedback produced via one par...
As mobile technologies such as cellular telephones reduce in both size and cost, and improve in fidelity, they become a more attractive option for performing tasks such as surfing the Web and accessing applications while on-the-go. The small size of the visual display limits the amount of information that can be presented, which may lead to clutter...
This paper describes an evaluation of a mobile exertion application, developed to promote physical activity among adult users. To extend previous work, we aimed to identify changes in walking behavior over time, and to determine the efficacy of non-visual cues presented via the phone. Data was gathered using three methods: automated logging, partic...
This paper describes the development of a non-visual memory game based on the classic game 'Simon™', where users are presented with a sequence of stimuli, which they need to replicate in the same order to progress to the next level. Information is presented using a combination of speech, non-speech audio and/or haptic cues, designed to aid blind us...
Older adults are recommended to remain physically active to reduce the risk of chronic diseases and to maintain psychological well-being. At the same time, research also suggests that levels of fitness can be raised among this group. This paper describes the development and evaluation of a mobile technology, which enables older adults to monitor an...
As levels of awareness surrounding accessibility increase, designers often look towards using nonvisual technologies to make existing graphical interfaces (e.g. Web pages) more inclusive. As existing haptic design guidance is not targeted to the specific needs of blind Web users, inappropriate touchable representations of graphical objects may be d...
This paper describes the design of an accessible authentication mechanism. The Tactile Authentication System has been adapted to enable individuals who are blind to access electronic data using their sense of touch. To enter the system, users must identify a set of pre-selected pin-based icons from a wider range presented via a tactile mouse. As in...
Recent developments in tactile technologies have made them an attractive choice to improve access to non-visual interfaces.
This paper describes the design and evaluation of an extension to an existing browser, which enables blind individuals to
explore web pages using tactile feedback. Pins are presented via a tactile mouse to communicate the pres...
This paper describes a novel approach to authenticate entry to a system using tactile feedback. The user is required to remember
a sequence of pre-selected pin patterns. A study has been undertaken to determine the feasibility of the tactile authentication
mechanism, through a comparison with a graphical scheme. Findings from a within-subjects stud...
This paper describes the development of a novel mobile phone-based application designed to monitor the walking habits of older adults. Haptic cues integrated within the prototype, are designed to inform an individual of changes which should be made to maintain a prescribed level of activity. A pilot study was conducted with fifteen older adults wal...
Research suggests that human limitations are rarely considered in the design of knowledge-based authentication systems. In an attempt to foster entry to a system, individuals tend to choose passwords which are easy to recall. However, inappropriate selection can compromise data security. A novel approach has been developed to restore the balance be...