The Development and Validation of the Technology-Supported Reflection Inventory

Reflection is an often addressed design goal in Human-Computer Interaction (HCI) research. An increasing number of artefacts for reflection have been developed in recent years. However, evaluating if and how an interactive technology helps a user reflect is still complex. This makes it difficult to compare artefacts (or prototypes) for reflection, impeding future design efforts. To address this issue, we developed the \emph{Technology-Supported Reflection Inventory} (TSRI), which is a scale that evaluates how effectively a system supports reflection. We first created a list of possible scale items based on past work in defining reflection. The items were then reviewed by experts. Next, we performed exploratory factor analysis to reduce the scale to its final length of nine items. Subsequently, we confirmed test-retest validity of our instrument, as well as its construct validity. The TSRI enables researchers and practitioners to compare prototypes designed to support reflection.Comment: CHI Conference on Human Factors in Computing Systems (CHI '21), May 8--13, 2021, Yokohama, Japa

Literature Reviews in HCI: A Review of Reviews

This paper analyses Human-Computer Interaction (HCI) literature reviews to provide a clear conceptual basis for authors, reviewers, and readers. HCI is multidisciplinary and various types of literature reviews exist, from systematic to critical reviews in the style of essays. Yet, there is insufficient consensus of what to expect of literature reviews in HCI. Thus, a shared understanding of literature reviews and clear terminology is needed to plan, evaluate, and use literature reviews, and to further improve review methodology. We analysed 189 literature reviews published at all SIGCHI conferences and ACM Transactions on Computer-Human Interaction (TOCHI) up until August 2022. We report on the main dimensions of variation: (i) contribution types and topics; and (ii) structure and methodologies applied. We identify gaps and trends to inform future meta work in HCI and provide a starting point on how to move towards a more comprehensive terminology system of literature reviews in HCI

Considering Wake Gestures for Smart Assistant Use

Smart speakers have become an almost ubiquitous technology as they enable users to access conversational agents easily. Yet, the agents can only be activated using specific voice commands, i.e. a wake word. This, in turn, requires the device to constantly listen to and process sound, which represents a privacy issue for some users. Further, using the trigger word for the agent in a conversation with another human may lead to accidental triggers. Here, we propose using gestural triggers for conversational agents. We conducted gesture elicitation to identify five candidate gestures. We then conducted a user study to investigate the acceptability and effort required to perform the gestures. Initial results indicate that the snap gesture shows the most potential. Our work contributes initial insights on using smart speakers with ubiquitous sensing

Considering Wake Gestures for Smart Assistant Use

10.1145/3334480.3383089CHI '20: CHI Conference on Human Factors in Computing System

Considering Wake Gestures for Smart Assistant Use

Smart speakers have become an almost ubiquitous technology as they enable users to access conversational agents easily. Yet, the agents can only be activated using specific voice commands, i.e. a wake word. This, in turn, requires the device to constantly listen to and process sound, which represents a privacy issue for some users. Further, using the trigger word for the agent in a conversation with another human may lead to accidental triggers. Here, we propose using gestural triggers for conversational agents. We conducted gesture elicitation to identify five candidate gestures. We then conducted a user study to investigate the acceptability and effort required to perform the gestures. Initial results indicate that the snap gesture shows the most potential. Our work contributes initial insights on using smart speakers with ubiquitous sensing

Critical evaluation of the performance of rhamnolipids as surfactants for (phyto)extraction of Cd, Cu, Fe, Pb and Zn from copper smelter-affected soil

Rhamnolipids are biosurfactants produced by bacteria belonging to the Pseudomonas genus. They are discussed to complex heavy metal cations stronger than cations of Fe, Ca, Mg. It is therefore suggested to employ rhamnolipids in phytoextraction where their addition to soil should result in preferential complexation of heavy metals that can be taken up by plants, thus enabling rapid and ecological clean-up of contaminated soil. In order to test this concept, we evaluated the rhamnolipid-mediated phytoextraction of heavy metal from soil collected from the vicinity of a copper smelter. The following aspects were investigated: i) selectivity of rhamnolipids towards Cu, Zn, Pb, Cd and Fe during soil washing; ii) phytoextraction efficiency of each ion with respect to the effective concentration of rhamnolipids; iii) possible phytotoxic effects; iv) effect of micro-sized polystyrene amendment. The experiments evaluated soil washing efficiency, BCR (Community Bureau of Reference) sequential extraction to determine the impact of rhamnolipids on the mobility of metal ions, phytoextraction with maize (Zea mays L.) and phytotoxic effects based on dry matter, chlorophyll fluorescence and content. The obtained results indicated that rhamnolipids lack desired selectivity towards heavy metal ions as Fe was complexed more efficiently by 80 % of the available rhamnolipids compared to priority pollutants like Zn, Cu, Pb, which were complexed by only 20 % of the tested rhamnolipids. With increased concentration of rhamnolipids, the soil washing efficiency increased and shifted in favour of Fe, reaching values of approx. 469 mg for Fe and only 118 mg in total of all tested heavy metals. Phytoextraction also favoured the accumulation of Fe, while Cd was not removed from the soil even at the highest applied rhamnolipid concentrations. Considering the selectivity of rhamnolipids and the costs associated with their production, our results suggest the need to search for other alternative (bio)surfactants with better selectivity and lower price