Complex schooling behaviors result from local interactions among individuals. Yet, how sensory signals from neighbors are analyzed in the visuomotor stream of animals is poorly understood. Here, we ...studied aggregation behavior in larval zebrafish and found that over development larvae transition from overdispersed groups to tight shoals. Using a virtual reality assay, we characterized the algorithms fish use to transform visual inputs from neighbors into movement decisions. We found that young larvae turn away from virtual neighbors by integrating and averaging retina-wide visual occupancy within each eye, and by using a winner-take-all strategy for binocular integration. As fish mature, their responses expand to include attraction to virtual neighbors, which is based on similar algorithms of visual integration. Using model simulations, we show that the observed algorithms accurately predict group structure over development. These findings allow us to make testable predictions regarding the neuronal circuits underlying collective behavior in zebrafish.
Existing research on control-transitions from automated driving (AD) to manual driving mainly stems from studies in virtual settings. There is a need for studies conducted in real settings to better ...understand the impacts of increasing vehicle automation on traffic safety. This study aims specifically to understand how drivers respond to take-over requests (TORs) in real traffic by investigating the associations between 1) where drivers look when receiving the TOR, 2) repeated exposure to TORs, and 3) the drivers' response process. In total, thirty participants were exposed to four TORs after about 5-6 min of driving with AD on public roads. While in AD, participants could choose to engage in non-driving-related tasks (NDRTs). When they received the TOR, for 38% of TORs, participants were already looking on path. For those TORs where drivers looked off path at the time of the TOR, the off-path glance was most commonly towards an NDRT item. Then, for 72% of TORs (independent on gaze direction), drivers started their response process to the TOR by looking towards the instrument cluster before placing their hands on the steering wheel and their foot on the accelerator pedal, and deactivating automation. Both timing and order of these actions varied among participants, but all participants deactivated AD within 10 s from the TOR. The drivers' gaze direction at the TOR had a stronger association with the response process than the repeated exposure to TORs did. Drivers can respond to TORs in real traffic. However, the response should be considered as a sequence of actions that requires a certain amount of time.
Abstract This study explores a potential joint effect between two proactive motives on creative performance. Departing from the assumption of motivation as a relatively stable between-person ...construct, we also pay attention to the within-person process to examine how daily fluctuations of proactive motives affect daily idea generation, leading to creative performance. Specifically, drawing on job demands–resources theory, we theorize a joint effect of two proactive motives at the within-person level: daily felt responsibility for change (DFRC) and daily willingness to take risks (DWTR). We test our hypotheses by analyzing data collected from 135 employees and their supervisors by using the experience sampling method followed by multiwave field surveys. Daily idea generation is high when the DFRC and DWTR have high congruence, particularly when both motives are high rather than low. In addition, daily idea generation mediates the effect of the DFRC and DWTR congruence on employee creative performance as appraised by supervisors. Moreover, seeking feedback from coworkers strengthens the indirect effect of the DFRC and DWTR congruence on employee creative performance via daily idea generation. This study offers a fine-grained view of motivational mechanisms and employee social behavior that lead to creative performance in the workplace.
The results of quantity take-off (QTO) based on building information modeling (BIM) technology rely heavily on the geometry and semantics of 3D objects that may vary among BIM model creation methods. ...Furthermore, conventional BIM models do not contain all the required information for automatic QTO and the results do not follow the descriptive rules in the standard method of measurement (SMM). This paper presents a new knowledge model-based framework that incorporates the semantic information and SMM rules in BIM for automatic code-compliant QTO. It begins with domain knowledge modeling, taking into consideration QTO-related information, semantic QTO entities and relationships, and SMM logic formulation. Subsequently, linguistic-based approaches are developed to automatically audit the BIM model integrity for QTO purposes, with QTO algorithms developed and used in a case study for demonstration. The results indicate that the proposed new framework automatically identifies the semantic errors in BIM models and obtains code-compliant quantities.
•Established a semantic data model for BIM-based QTO.•Formulated the SMM descriptive rules to support automatic and accurate QTO.•Developed a linguistic-based approach to semantic auditing for QTO purposes.•Developed new algorithms for automatic measurement of modeled and unmodeled elements.•Verified the algorithms with >99% compliance with SMM in different scenarios.
•Research on automation and safety is in ‘silos’ for each transport mode.•There are several opportunities for transfer of knowledge between transport modes.•Lessons from aviation on automation trust, ...SA and the role of training are transferable.•The quantitative approach of the road sector to SA and takeover performance can be transferable.•Relevant research in maritime and rail is limited.
One of the main aims of introducing automation in transport is to improve safety by reducing or eliminating human errors; it is often argued however that this may induce new types of errors. There is different level of maturity with automation in different transport modes (road, aviation, maritime and rail), however no systematic research has been conducted on the lessons learned in different sectors, so that they can be exploited for the design of safer automated systems. The aim of this paper is to review the impact of key human factors on the safety of automated transport systems, with focus on relevant experiences from different transport sectors. A systematic literature review is carried out on the following topics: the level of trust in automation – in particular the impact of mis-aligned trust, i.e. mistrust vs overreliance, the resulting impact on operator situation awareness (SA), the implications for takeover control from machine to human, and the role of experience and training on using automated transport systems. The results revealed several areas where experiences from the aviation and road domain can be transferable to other sectors. Experiences from maritime and rail transport, although limited, tend to confirm the general patterns. Remarkably, in the road sector where higher levels of automation are only recently introduced, there are clearer and more quantitative approaches to human factors, while other sectors focus only on mental modes. Other sectors could use similar approaches to define their own context-specific metrics. The paper makes a synthesis of key messages on automation safety in different transport sectors, and presents an assessment of their transferability.
The Winner-Take-All circuit is an important part of the competition layer in the competitive neural network. Its main function is to compare the size of the output of the nodes after the weighted ...summation of all input vectors, and select the node with the largest output to output high power level, while other nodes output low level, that is, to find the node with the largest output. According to the characteristics of the Winner-Take-All circuit in the competitive neural network, the simulation of the Winner-Take-All circuit is carried out by the PSPICE simulation software. The physical test results show that, like the simulation diagram of the Winner-Take-All circuit, it conforms to the logic truth table, which further confirms the rationality and correctness of the Winner-Take-All circuit. Hardware realization of Winner-Take-All circuit as an important component of competitive layer in competitive neural networks has important research significance.
To systematically investigate factors affecting consumers' restaurant patronage decisions during the COVID-19 pandemic, this study drew on the Protection Motivation Theory (PMT) to (1) evaluate how ...threat and coping appraisal (i.e., PMT factors) may vary based on socio-demographics and COVID-19 situational characteristics, and (2) determine if PMT factors influence actual restaurant patronage behaviors. Furthermore, the current study examined consumers' perceptions of health-protective actions that restaurateurs could take to minimize consumer risk of contracting COVID-19. Data were collected from U.S. adults (N = 627) using an online crowdsourcing platform in early May 2020. Findings showed significant relationships between socio-demograhic factors and perceived severity and/or vulnerability to COVID-19, along with concerns of coping with the virus for in-restaurant dining. For take-out/delivery patronage, coping concerns were greater for those with lower education levels and those with more health concerns than their counterparts. Furthermore, consumers' higher levels of coping appraisal predicted their higher take-out/delivery frequency. Results also suggested actions that restaurateurs could take that would influence consumers' restaurant patronage decisions. This study provides new insights related to PMT in the context of restaurants in a pandemic situation and practical information for restaurateurs to recover and prepare for future pandemics or similar crises.
Converting persistent and renewable wave energy into electricity has been a research focus in recent years. The oscillating-body wave energy converter (WEC) is a promising approach, especially for ...offshore areas. However, conventional oscillating-body WECs with linear power take-off (PTO) systems are less efficient under off-resonance conditions and have a narrow power capture bandwidth, which has inhibited the commercial application of wave energy. In order to enhance the power capture performance, this study examined oscillating-body WECs with three new types of PTO systems: bistable impulsive PTO, coupled linear PTO, and coupled bistable PTO. Governing equations for the heave motion of a WEC were established based on the linear potential theory by coupling the buoy and PTO systems and were numerically calculated with the fourth-order Runge–Kutta method. The influence of PTO parameters such as the spring constant, stable equilibrium position, and mass ratio on the power capture ratio was investigated. The differences among the WECs with different PTOs were analysed to determine the optimum device. Compared with the linear PTO system, the WEC with the bistable impulse PTO system enhanced the power capture ratio for low-frequency regular waves, and WECs with coupled linear or coupled bistable PTO systems increased the power capture ratio for low-frequency regular waves and expanded the power capture spectrum bandwidth when proper PTO parameters were applied.
•Three new power take-off (PTO) systems for a wave energy converter (WEC).•Influence of PTO parameters on the power capture ratio was studied.•WEC with bistable PTO can enhance power capture ratio at low-frequency waves.•WECs with coupled (linear or bistable) PTOs expand power capture spectrum bandwidth.
In this paper, a novel discrete control strategy is proposed to improve power-capture performance of wave energy converters (WECs) with a hydraulic power take-off (PTO) system. In this novel discrete ...control strategy, separate switching valves are introduced such that each chamber of hydraulic cylinders can be actively and independently connected to a high-pressure gas accumulator or a low-pressure gas accumulator by controlling the switching action of the switching valves. Thus, it increases the flexibility of the PTO system and makes the PTO system more controllable. The effectiveness of the novel discrete control on improving power-capture performance of a raft-type WEC and the optimal switching command of the switching valves for maximizing power capture are studied. Benefit brought by the novel discrete control is investigated in terms of power improvement and the control effect of the novel discrete control is compared with that of load control and latching control. Results show that the novel discrete control can effectively improve power-capture performance of the raft-type WEC and theoretically the corresponding benefit reaches a peak value of 2 and 2.5 in regular and irregular waves, respectively. The novel discrete control has an advantage over load control and can be complementary to latching control.
•A novel discrete control is proposed to improve power capture of WECs.•Effectiveness and optimal switching command of the novel control are studied.•Benefit due to the novel control in terms of power improvement is investigated.•Controls effect of the novel control, load control and latching control are compared.•The novel control is superior to load control and complementary to latching control.
Most genetic variants associated with adult height have been identified through large genome-wide association studies (GWASs) in European-ancestry cohorts. However, it is unclear how these variants ...influence linear growth during adolescence. This study uses anthropometric and genotypic data from a longitudinal study conducted in an American Indian community in Arizona between 1965-2007. Growth parameters (i.e. height, velocity, and timing of growth spurt) were derived from the Preece-Baines growth model, a parametric growth curve fitted to longitudinal height data, in 787 participants with height measurements spanning the whole period of growth. Heritability estimates suggested that genetic factors could explain 25% to 71% of the variance of pubertal growth traits. We performed a GWAS of growth parameters, testing their associations with 5 077 595 imputed or directly genotyped variants. Six variants associated with height at peak velocity (P < 5 × 10-8, adjusted for sex, birth year and principal components). Implicated genes include NUDT3, previously associated with adult height, and PACSIN1. Two novel variants associated with duration of growth spurt (P < 5 × 10-8) in LOC105375344, an uncharacterized gene with unknown function. We finally examined the association of growth parameters with a polygenic score for height derived from 9557 single nucleotide polymorphisms (SNPs) identified in the GIANT meta-analysis for which genotypic data were available for the American Indian study population. Height polygenic score was correlated with the magnitude and velocity of height growth that occurred before and at the peak of the adolescent growth spurt, indicating overlapping genetic architecture, with no influence on the timing of adolescent growth.
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