Farzan Sasangohar

Evaluation of Mouse and Touch Input for a Tabletop Display Using Fitts' Reciprocal Tapping Task

User performance with a tabletop display was tested using touch-based and mouse-based interaction in a traditional pointing task. Dependent variables were throughput, error rate, and movement time. In a study with 12 participants, touch had a higher throughput with average of 5.53 bps compared to 3.83 bps for the mouse. Touch also had a lower movement time on average, with block means ranging from 403 ms to 1051 ms vs. 607 ms to 1323 ms with the mouse. Error rates were lower for the mouse at 2.1%, compared to 9.8% for touch. The high error rates using touch were attributed to problems in selecting small targets with the finger. It is argued that, overall, touch input is a preferred and efficient input technique for tabletop displays, but that more research is needed to improve touch selection of small targets.

Not All Interruptions are Created Equal: Positive Interruptions in Healthcare

Interruptions were studied extensively in the past but with a focus on their negative effects. Although many types of interruptions result in a break-in-task, in some cases interruptions communicate important information associated with patient’s safety. The majority of previous interruption research use a reductionist approach to minimize or prevent interruptions, and minimal attention has been given to the differentiation between positive and negative interruptions. Through the analysis of relevant healthcare literature, this paper first identifies the inconsistencies in the way interruptions are defined, and then categorizes potential sources of negative and positive interruptions.

Interruptions experienced by cardiovascular intensive care unit nurses: an observational study.

PURPOSE Intensive care unit (ICU) nurses get interrupted frequently. Although interruptions take cognitive resources from a primary task and may hinder performance, they may also convey critical information. Effective management of interruptions in ICUs requires the understanding of interruption characteristics, the context in which interruption happens, and interruption content. METHODS An observational study was conducted in a cardiovascular ICU at a Canadian teaching hospital. Four observers (1 PhD and 3 undergraduate students) trained in human factors research observed 40 nurses, approximately 1 hour each, over a 3-week period. Data were recorded by the observers in real time, using touchscreen tablet PCs and special software designed for this purpose. RESULTS Although approximately half of the interruptions (~51%) happened during high-severity tasks, more than half of these interruptions, which happened during high-severity tasks, conveyed either work- or patient-related information. Furthermore, the rate of interruptions with personal content was significantly higher during low-severity tasks compared with medium- and high-severity tasks. CONCLUSIONS Mitigation strategies other than blocking should also be explored. In addition, interrupters might have evaluated primary task severity before interrupting. Therefore, making task severity more transparent may help others modulate when and how they interrupt a nurse.

Supervisory-level interruption recovery in time-critical control tasks

This paper investigates the effectiveness of providing interruption recovery assistance in the form of an interactive visual timeline of historical events on a peripheral display in support of team supervision in time-critical settings. As interruptions can have detrimental effects on task performance, particularly in time-critical work environments, there is growing interest in the design of tools to assist people in resuming their pre-interruption activity. A user study was conducted to evaluate the use of an interactive event timeline that provides assistance to human supervisors in time-critical settings. The study was conducted in an experimental platform that emulated a team of operators and a mission commander performing a time-critical unmanned aerial vehicle (UAV) mission. The study results showed that providing interruption assistance enabled people to recover from interruptions faster and more accurately. These results have implications for interface design that could be adopted in similar time-critical environments such as air-traffic control, process control, and first responders.

Mapping complexity sources in nuclear power plant domains

Understanding the sources of complexity in advanced Nuclear Power Plant (NPP) control rooms and their effects on human reliability is critical for ensuring safe performance of both operators and the entire system. New generation control rooms will rely more heavily on automation and computerized Human-System Interfaces (HSI). Without proper management, information representation and required operator-system interaction could challenge operator information processing capabilities. This paper provides an initial step in assessing the sources of complexity in the NPP control rooms and introduces a systems-theoretic descriptive model of these sources of complexity leveraging network theory.

Stress, fatigue, and workload in intensive care nursing: A scoping literature review

Stress and fatigue are being interchangeably used in the nursing literature resulting in operationalization and measurement issues. A scoping review was conducted to identify different definitions and operationalization of these constructs. Findings can be used to develop tools to measure stress and fatigue as different constructs to aid nursing administrators to gain a new perspective into nursing schedule, workload, morale and well-being of nurses. The findings show that there is a research gap in measurement of acute stress in nursing, physiological measures are currently not used for continuous assessment of stress or fatigue for nurses, and lack of stress and fatigue definitions in terms of physiological measures for assessment purposes. Continuous monitoring and physiological measures such as heart rate can be used to measure and differentiate between the constructs of stress and fatigue

Passenger-Driver Distinguishing Test for Pokémon Go

Distracted driving while gaming is a serious hazard especially for young drivers. Increasing popularity of augmented reality games may increase distracted driving incidents. The main purpose of this study is to test the feasibility of an identification test to differentiate between drivers and passengers to prevent drivers from playing augmented reality games while driving to reduce distracted driving incidents. We hypothesized that increased cognitive burden will reduce vigilance on the secondary task which will reduce attention and increase the risk associated with the secondary task. An experiment with a driving simulator tested university students’ performance to evaluate the efficacy of the distinguishing test. The results show that the test shows promise to distinguish between drivers and passengers. Such tests can be used in applications when users perform two tasks that require the same modality leading to decreased performance in both tasks.

Objective Assessment of Functional Information Requirements for Patient Portals

There has been an increase in the usage of electronic health records by healthcare providers as a result of recent federal incentive programs. One benefit of electronic systems is providing patients remote access to their records and an online interface with their healthcare provider via a patient portal. Patients, however, have been slow to adopt these systems and many studies have been conducted in attempts to investigate such slow adoption. It is not clear if the users were involved in the design of such systems and if the functionality meets user expectation. This paper aims to address this issue by documenting a comprehensive and systematically-derived set of functional and information requirements for patient portals based on a review of literature and interviews with patients.

Investigating Written Procedures in Process Safety: Qualitative Data Analysis of Interviews from High Risk Facilities:

Socio-technical systems, such as those in oil and gas, or the petrochemical and energy industries, are escalating in complexity, a consequence of increasingly advanced technologies, organizational constructs, and business functions that interact and depend on one another. These dynamic social and technological elements, coupled with the high risk inherent in these systems, have generated conditions that can bring about catastrophic failure and the tragic loss of human life, such as the disaster in Bhopal, India (1984) or the explosion in the Houston Ship Channel near Pasadena, Texas (1989). Historically, the perception of such complexities and the struggle to minimize catastrophic failures observed within the petrochemical industry have been attributed to the inherent variability in people. Therefore, process safety regulations associated with the Clean Air Act Amendments of 1990 and the Occupational Safety and Health Administration (OSHA) require employers to develop written process safety information or “procedures” which aim for consistency in plant operations and to help workers at the “sharp-end” of the system cope with unexpected events (OSHA, 2000). However, investigation reports since, such as the BP Texas City incident of 2005, suggest “outdated and ineffective procedures” as significant contributing factors to failure. Evidence from other studies suggest that procedures in complex environments are sometimes misunderstood, outdated, or simply not used (Bullemer & Hajdukiewicz, 2004). While there have been studies on procedural deviations and safety violations (Alper & Karsh, 2009; Jamison & Miller, 2000), employers continue to report a high rate of procedural breakdown as root causes for incidents (Bates & Holroyd, 2012). This warrants a contemporary, systems-oriented inquiry into process safety and behavior surrounding the use of the documents at different individual (e.g. cognitive), task, cultural, organizational, and environmental levels. This perspective appreciates the interdependent nature of these interrelated socio-technical elements and should provide insight into the effectiveness of current procedure systems, thereby informing future work in creating and empirically testing mitigation methods to address potential barriers. This research documents one part of a three part, large-scale project that investigates the issues with procedure forms, usage, adoption, and challenges in a wide range of high-risk industries. As such, the method was framed around first understanding the extent to which these challenges could be generalized between various locations. A grounded theory approach in qualitative data analysis, influenced by the Strauss & Corbin and Charmaz approaches (Bryman 2015) and facilitated by the analysis software MAXQDA-12 was used to examine 72 semi-structured interviews with operators of varying roles and experiences across 6 countries and an offshore drilling vessel. Findings reaffirm previous research, suggesting that the effectiveness of written procedures is limited by an abundance of outdated procedures plagued by information overload. New findings suggest that frequency of the task and the experience level of the worker would impact workers’ procedure use, with participants commenting that the perceived importance of these documents decreases significantly after initial training periods. Other unintended consequences associated with written procedural systems range from complications in using the documents around personal protective equipment (PPE) requirements and harsh weather, reactive organizational behavior surrounding changing procedures, and a general disconnect between the users and the writers of these documents. This is only exacerbated as management imposes pressure to use procedures on personnel despite the issues encountered with the documents, inhibiting valuable feedback within their organizations as personnel withhold information for fear of job security and potential punishment (in the form of 20-day suspension programs or termination). Moving forward, research is in-progress to identify the interdependencies between environmental, cultural, organizational, task, and personal factors unique to each location. This will provide insight regarding the extent to which procedures may not be generalized, after which a holistic view of procedure use in the industry will be offered. The resulting insight will point to recommendations for the future redesign of procedures’ role in promoting safe operations within petrochemical systems. Finally, the third part of this research project will demonstrate the efficacy of using visualizations as tools and methods in qualitative research for modeling complexity in socio- technical systems.

Measuring Fatigue through Heart Rate Variability and Activity Recognition: A Scoping Literature Review of Machine Learning Techniques

A scoping literature review was conducted to summarize the current research trends in fatigue identification with applications to human activity recognition through the use of diverse commercially available accelerometers. This paper also provides a brief overview of heart rate variability and its effect on fatigue. The linkage between recognizing an individual’s unique physical activities, and its possible feedback to manage fatigue levels were explored. Overall, triangulation of heart rate variability and accelerometer data show promise in identify chronic cognitive and physical fatigue levels.