On the skin, a small distance between two actuators can result in the perception of a single, centralized stimulus rather than two distinct stimuli - this phenomenon is known as the funneling illusion. In this work, we explore the electrotactile funneling illusion on the forearm in a user study with 16 participants. We placed an electrode strip with 9 electrode pairs along their forearm - from wrist to elbow. The calibration of the same perceived intensity of each electrode pair for each participant shows that the calibrated intensities near the wrist are significantly higher compared to the intensities calibrated near the elbow. A linear regression corresponds to this behavior as well as the qualitative feedback of our participants. Based on this, we created an equation that helps to reduce the calibration time considerably. The results of our study show that the funneling illusion can be reliably evoked at distances of up to 7.2 cm. Further, we provide detailed information on occurrence frequency and precision and explored whether an approach adapted for electrotactile feedback can create an apparent tactile motion.

Prior research has designed and evaluated Voice Assistance (VA) for different settings such as the home, school, and public spaces. Office environments have been relatively understudied, leaving a gap in understanding the essential factors for designing a VA specifically for work settings. In this study, we developed the WorkFit VA specific for the office environment, focusing on the health and well-being of knowledge workers. WorkFit was designed to monitor knowledge workers for sedentary behavior, inconsistent hydration, and stress, and to deliver proactive voice interventions followed by a health recommendation to mitigate those issues. We evaluated WorkFit in a field study with 15 knowledge workers for 5 working days. In the study, we determined challenges and opportunities for voice interactions in work settings. We identified contextual factors for identifying inopportune moments for voice interactions in an office setting. We found that 92% of knowledge workers accepted WorkFit’s hydration interventions while 79% of them engaged in walking breaks. Moreover, breathing exercises recommended by WorkFit significantly stabilized the heart rate of knowledge workers during stress. Based on our findings, we propose five design recommendations for the development of VA customized to office settings.

Operating small touchscreens with the finger occludes a large part of the screen. We propose using the watch case as the input space, without enlarging the smartwatch. Therefore, we created two prototypes, one with a touch surface on the watch case (CASE) and one with touch surfaces on the watch case and the wristband (CASE+BAND). In a comparative study, we analyze their suitability in a 1D list scrolling task and 2D map navigation task. The results show that occlusion is less of a problem for the list scrolling task, as visibility is sufficient. In the map navigation task, participants reached task completion times with CASE+BAND that are comparable to touch input. CASE was significantly slower, but only requires minimal additional hardware. However, the results of a subsequent longitudinal study demonstrates the learnability of CASE, which led to task completion times comparable to touch input, and provides insights in the gradual development of expert performance.

Cycling navigation is a complex and stressful task as the cyclist needs to focus simultaneously on the navigation, the road, and other road users. We propose directional electrotactile feedback at the wrist to reduce the auditory and visual load during navigation-aided cycling. We designed a custom electrotactile grid with 9 electrodes that is clipped under a smartwatch. In a preliminary study we identified suitable calibration settings and gained first insights about a suitable electrode layout. In a subsequent laboratory study we showed that a direction can be encoded with a mean error of 19.28\,° (σ = 42.77°) by combining 2 adjacent electrodes. Additionally, by interpolating with 3 electrodes a direction can be conveyed with a similar mean error of 22.54° (σ = 43.57°). We evaluated our concept of directional electrotactile feedback for cyclists in an outdoor study, in which 98.8% of all junctions were taken correctly by eight study participants. Only one participant deviated substantially from the optimal path, but was successfully navigated back to the original route by our system.

Wildfire is an integral part of many ecosystems, and wildland fires also have the potential for costly impacts to human health and safety, and damage to structures and natural resources. Public land managers use various strategies for managing landscape conditions that can affect wildfire, broadly: fuel treatment (and other pre-fire risk mitigation), fire suppression, and post-fire landscape rehabilitation. However, with any of these strategies there is considerable uncertainty in the outcomes that managers can obtain, and thus on the societal costs and benefits associated with wildland fire management. Managers address that uncertainty by using available information to inform their strategy choices. The value of information (VOI) to the land manager is defined as the expected gains from improved wildland fire management outcomes that result from using the information. This paper discusses estimating the value of information using two approaches: a microeconomic theoretical approach, and the Bayesian decision-tree approach frequently used in the VOI literature. These approaches could be used for valuing specific pieces of information (with absolute values), and for prioritizing (with relative values) which areas to focus on for future research.

Recent research in Human-Computer Interaction for work has shown that conversational agents (CA) are beneficial for supporting focused work and well-being while at work. Knowledge workers struggle in maintaining focus, work schedule, and well-being. Typically, they rely on multiple tools and services for work productivity, scheduling tasks, and reminding breaks. With the goal of tackling these problems, we propose the concept of a ubiquitous work assistant (UWA), which consists of two components: a stationary CA (S-CA) and a wearable CA (W-CA). S-CA is meant to be placed on user’s work desk while W-CA is fixed on the user’s wrist. The UWA interface is distributed between S-CA and W-CA. We initiated our study by conducting semi-structured interviews with knowledge workers (N = 14). We identified their expectations from conversational agents (CAs) that would assist them in their daily work life. From the interview findings, we developed an UWA prototype that could assist users by briefing their daily schedule, monitoring their schedule, and reminding breaks. We conducted a lab study simulating a home-office environment. The findings of the study show that the knowledge workers see potential in the UWA system. Further, we discuss implications of distributed user interface (DUI) for UWA design.

The link between religions and several issues of contemporary relevance lead to the need for interreligious dialogue today. However, interreligious dialogue is not about creating a unifying hermeneutic leading to convergence, as many approaches in our day tend to be. For religions to be in fruitful conversation, there is no need for levelling differences and denying one's own convictions. Core theological convictions need not be up for discussion in dialogue. Rather, a hermeneutic of difference may be used that allows differences to stand in a respectful space. An interreligious conviviality that allows dialogue participants to learn from each other, share with each other, and celebrate with each other can lay perspectives for an interreligious future.

Creating tactile patterns on the body via a spatial arrangement of many tactile actuators offers many opportunities and presents a challenge, as the design space is enormous. This paper presents a VR interface that enables designers to rapidly prototype complex tactile interfaces. It allows for painting strokes on a modeled body part and translates these strokes into continuous tactile patterns using an interpolation algorithm. The presented VR approach avoids several problems of traditional 2D editors. It realizes spatial 3D input using VR controllers with natural mapping and intuitive spatial movements. To evaluate this approach in detail, we conducted a user study and iteratively improved the system. The study participants gave predominantly positive feedback on the presented VR interface (SUS score 79.7, AttrakDiff “desirable”). The final system is released alongside this paper as an open-source Unity project for various tactile hardware.

Microplastiques en estuaire de Seine : synthese des connaissances du projet Plastic-Seine sur les matrices abiotiques (2017-2020) GASPERI Johnny Le projet PLASTIC-Seine (Flux et impacts des microplastiques dans l’estuaire de la Seine, 2017-2020) avait pour objectif d’etudier de maniere integree l’occurrence et les niveaux d’impregnation de l’estuaire de la Seine par les microplastiques (MP), qu’il s’agisse de la colonne d’eau, du sediment ou du biote. Structure autour de trois tâches, le projet visait a 1) dresser un etat des lieux de la contamination des compartiments abiotiques sur le fleuve, 2) etudier la contamination par les MP de sept especes representatives du reseau trophique de l’estuaire de Seine et 3) mieux comprendre le transfert, le devenir et les effets des MP dans trois des sept especes selectionnees. Sur le premier point, les travaux menes demontrent l’ubiquite des MP au sein des matrices abiotiques. Ils soulignent d’une part le role majeur joue par le sediment dans le transfert et le devenir des MP. Ils mettent egalement en evidence une evolution des concentrations en MP le long du gradient salin. L’etude de deux cycles de maree a montre l’existence des forts gradients de concentration au cours du temps, mais egalement au sein de la colonne d’eau. Ces gradients peuvent s'expliquer a la fois par la remise en suspension des sediments de fond, riches en MP, lors du flot et par la sedimentation des particules lors du jusant. Ces travaux ont ete finances par le GIP Seine Aval et l'Agence de l'Eau Seine Normandie.

Tactile patterns are a means to convey navigation instructions to pedestrians and are especially helpful for people with visual impairments. This article presents a concept to provide precise micro-navigation instructions through a tactile around-the-head display. Our system presents four tactile patterns for fundamental navigation instructions in conjunction with continuous directional guidance. We followed an iterative, user-centric approach to design the patterns for the fundamental navigation instructions, combined them with a continuous directional guidance stimulus, and tested our system with 13 sighted (blindfolded) and 2 blind participants in an obstacle course, including stairs. We optimized the patterns and validated the final prototype with another five blind participants in a follow-up study. The system steered our participants successfully with a 5.7 cm average absolute deviation from the optimal path. Our guidance is only a little less precise than the usual shoulder wobbling during normal walking and an order of magnitude more precise than previous tactile navigation systems. Our system allows various new use cases of micro-navigation for people with visual impairments, e.g., preventing collisions on a sidewalk or as an anti-veering tool. It also has applications in other areas, such as personnel working in low-vision environments (e.g., firefighters).

The vibrotactile funneling illusion is the sensation of a single (non-existing) stimulus somewhere in-between the actual stimulus locations. Its occurrence depends upon body location, distance between the actuators, signal synchronization, and intensity. Related work has shown that the funneling illusion may occur on the forehead. We were able to reproduce these findings and explored five further regions to get a more complete picture of the occurrence of the funneling illusion on the head. The results of our study (24 participants) show that the actuator distance, for which the funneling illusion occurs, strongly depends upon the head region. Moreover, we evaluated the centralizing bias (smaller perceived than actual actuator distances) for different head regions, which also showed widely varying characteristics. We computed a detailed heat map of vibrotactile localization accuracies on the head. The results inform the design of future tactile head-mounted displays that aim to support the funneling illusion.

Nowadays, microplastic (MPs) pollution is well documented in marine ecosystems since the first publication alarming about marine plastic pollution in 1972 [1]. Similarly, continental contamination is more and more investigated. More recently, interest for estuarine systems is growing. Estuaries are considered as a suspected predominant pathway for microplastic pollution from continent to oceans. The specific conditions of estuaries, like salinity gradient, tides and hydrodynamics, could affect the repartition, settling and transfer of microplastics to marine systems.

Habitat conservation banking is often identified as a policy instrument for conserving endangered species on private lands in the United States. In this paper, we analyze the trends and the characteristics of habitat conservation bank credit supply and demand. We find 137 conservation banks conserving some 153,000 acres of land. About 66% of conservation credits were sold by private companies and credit price ranges between $1505 and $205,055 per credit in constant 2015 dollars. We observe that large urban areas have relatively high demand for conservation credits and that habitat conservation banking has become a business.

Phytoplankton primary production varies considerably with environmental parameters especially in dynamic ecosystems like estuaries. The aim of this study was to investigate short-term primary production along the salinity gradient of a temperate estuary over the course of 1 year. The combination of carbon incorporation and fluorescence methods enabled primary production estimation at short spatial and temporal scales. The electron requirement for carbon fixation was investigated in relation with physical-chemical parameters to accurately estimate primary production at high frequency. These results combined with the variability of the photic layer allowed the annual estimation of primary production along the estuary. Phytoplankton dynamics was closely related to salinity and turbidity gradients, which strongly influenced cells physiology and photoacclimatation. The number of electrons required to fix 1 mol of carbon (C) was ranged between 1.6 and 25 mol electron mol C −1 with a mean annual value of 8 ± 5 mol electron mol C −1 . This optimum value suggests that in nutrient replete conditions like estuaries, alternative electron flows are low, while electrons transfer from photosystem II to carbon fixation is highly efficient. A statistical model was used to improve the estimation of primary production from electron transport rate as a function of significant environmental parameters. Based on this model, daily carbon production in the Seine estuary (France) was estimated by considering light and photic zone variability. A mean annual daily primary production of 0.12 ± 0.18 g C m −2 day −1 with a maximum of 1.18 g C m −2 day −1 in summer was estimated which lead to an annual mean of 64.75 g C m −2 year −1 . This approach should be applied more frequently in dynamic ecosystems such as estuaries or coastal waters to accurately estimate primary production in those valuable ecosystems.

This paper presents an econometric analysis of factors influencing the demand and supply of habitat conservation credit markets in the United States. Two-stage least squares is used. The results suggest that both the demand and supply for habitat conservation credits are inelastic. The results also suggest that the availability of habitat conservation credits (and new habitat bank formation) is likely to decrease with increases in land value. These results are only suggestive as the dataset used has some significant limitations. Data challenges point to the need for greater public availability of transaction-level data. The availability of such data can help improve the modelling efficiency of habitat conservation banking markets.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Microplastic contamination in the Seine River estuary Soline Alligant, Johnny Gasperi, Aline Gangnery, Franck Maheux, Benjamin Simon, Marie-Pierre Halm-Lemeille, Maria El Rakwe, Catherine Dreanno, Jerome Cachot, Bruno Tassin

The missionary movement in the 20th century started with the Edinburgh World Missionary Conference in 1910. At that time the aim was to evangelize the world in that generation. Examining the next Conferences on World Mission and Evangelism, especially Willingen (1952), reveals a paradigm shift in the understanding of mission. Mission is not about conversion, but about the three Ts: translation, transmission, and transformation. Since Arusha (2018) it has become even more obvious that mission theology needs to translate the gospel - also figuratively - into different contexts and cultures, including subcultures in our own culture and in secular contexts. It needs to transmit the gospel. Being witnesses of Christ in our world by being able to speak about our own faith is crucial when we consider the Western contexts and the distancing of the younger generation. The third T defining mission is transformation - a far more radical term than we may have wished, as it is about "turning the world upside down" (Acts 17.6). By focusing on these three Ts, mission becomes "a way of life" (Together towards Life 29).

This paper presents a mission planning problem for a cooperative team of unmanned ground vehicles (UGVs), which includes multiple rovers and a solar-powered mobile charging station. The team is required to start at an initial point and visit a series of objective points before arriving at the final point selected from the set of objective points, where the UGVs will be charged from the solar-powered mobile charging station. This mission is represented as a multi-Hamiltonian Path Problem (mHPP). In order to effectively coordinate the team, an understanding of the mission environment is first obtained by generating a scalar field representation of the solar insolation of the environment from a visual-spectrum image. Then, a cascaded heuristic optimization algorithm, using modified genetic algorithm and particle swarm optimization, is used to generate a time-optimized mission plan for the team of UGVs, which guides each UGV to its assigned objective points and then rendezvous at the final charging location while guaranteeing compliance with the net energy gain constraint. The feasibility and efficiency of the proposed algorithm are verified using an experimental testbed and constructed indoor simulation environments.