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关键词： Ambulatory assessment   Heart rate variability   State mindfulness   Occupational well-being   Emotional exhaustion   Relaxation  

摘要： Objective: Heart rate variability (HRV) and mindfulness have been described as correlates of self-regulation and well-being. The goal of the present study was to investigate their interactions from a within-person perspective in the context of work. Methods: Applying an ambulatory assessment approach, we studied 89 healthcare professionals across two to four work shifts. Self-reports of momentary job demands, mindfulness, and well-being (as indicated by emotional exhaustion, relaxation, and contentment) were provided three to four times a day via smartphone questionnaires. Electrocardiogram and activity sensors continuously recorded data from the beginning to the end of the shifts. Multilevel models based on 937 measurements were built for emotional exhaustion, relaxation, and contentment. Results: After controlling for covariates, including bodily movement, shift, and job demands, short-term HRV was marginally significantly related to decreased emotional exhaustion and significantly related to increased relaxation. State mindfulness was significantly related to decreased emotional exhaustion, and increased relaxation and contentment. Furthermore, HRV and mindfulness significantly interacted such that emotional exhaustion was lowest and relaxation was highest when both HRV and mindfulness were high. Conclusions: Together, the findings provide insights into the use of HRV and mindfulness as indexes of psychophysiological regulatory resources that seemingly intensify their respective beneficial effects on the daily wellbeing of employees.

关键词： Entropy   Time series analysis   Euclidean distance   Complexity theory   Time measurement   Informatics   Computer science   Artificial neural network   fault diagnosis   fuzzy entropy   multiscale entropy (MSE)   time series complexity  

摘要： Sample entropy (SampEn) technologies have been widely applied in diagnosing the faults of industrial systems. However, there are two disadvantages of these technologies. First, all of these technologies measure the distance of two vectors solely based on the maximum distance between the corresponding elements in the two vectors, which is not able to fully reflect the distance of the two vectors. Second, these methodologies measure the similarity of two vectors with either zero or one, which may cause sudden changes in entropy values. Therefore, we proposed a Euclidean distance based multiscale fuzzy entropy (EDM-Fuzzy), which measures the similarity of two vectors with continuous values from zero to one based on the Euclidean distance of the two vectors. The results from the synthetic and real signals demonstrated that EDM-Fuzzy has higher accuracy in measuring the complexity of signals. As a result, EDM-Fuzzy obtains a higher accuracy in detecting the bearing faults than the state-of-the-art entropy technologies.

关键词： Computer science education   Anti-Blackness   BlackCrit   Speculative fiction   Abolition   Black Life  

摘要： Computer science (CS) education finds itself at a pivotal moment to reckon with what it means to accept, use, and create technologies, with the continued recruitment of minoritized students into the field. In this paper, we build on the oral traditions of educating with stories, and take the reader on two journeys. We begin with a story that leads us in thinking about where computer science education is, in the wake of slavery, under the New Jim Code. Within a BlackCrit framework, we shake the grounds of the computer science field, where technologies are often promoted as objective, but reflect and reproduce existing inequalities. In tune with maintaining current systems of power, efforts to broaden participation in computer science have been heavily driven by industry, government, and military interests. These interests ultimately push us farther away from sustainable relations with the earth and with each other, and risk the very lives of the same communities the field claims to help. However, we can rewrite the narratives of the role of technology in our lives. We present a second story in which we place abolitionist theories and practices in conversation with computer science education. In this paper we explore (1) In what ways does computing education support systems that enable Black death? and (2) How might integrating an abolitionist framework into computer science open up possibilities for world-building and dreaming in the name of Black Life? We imagine a different future where computer science is used as a tool in life-affirming, world-building projects. We invite readers to engage with this piece as a part of an active dialogue towards combating anti-Black logics in the field of computer science education.

关键词： Allocentric   Coding toys   Computer science   Early childhood   Egocentric   Reference frames   Syntonicity  

摘要： This research explores reference frames and reference frame shifts among young children (ages 5 and 6) as they are learning to program with a commercial coding toy. To date, little is known about reference frames used by young children in toy-based coding. Video recordings of 16 children engaging in two programming tasks were collected. Results from an analysis of 240 min of video data indicate that young children engage in shifts of reference frames when learning to program, however, young children do not have a precise coordination system. The present study proposes two additional reference frames, ProtoEgocentric and ProtoAllocentric, that allow for the consideration of developmental imprecision in children. The most common reference frame shift observed was ProtoAllocentric to ProtoEgocentric, which accounted for 47.4% of all shifts across sites and contexts. Three cases are presented to illustrate reference frame shifts and how children's developmental imprecision affects their experience. © 2021 Elsevier B.V.

关键词： Onion flakes   Dried cabbages   Dried green beans   Browning   Chlorophyll  

摘要： In an attempt to get the overall picture of shelf life dynamics of packaged dried foods, a mathematical simulation model consisting of differential equations of water vapor transmission and quality change was established and solved numerically through the interactive relationships of moisture sorption isotherm, package water vapor permeability and quality deterioration kinetics to predict moisture content and quality changes throughout storage. Estimated shelf lives based on moisture increase and primary quality change as the decision criteria were examined for dried onion flakes, cabbage and green beans packaged in a hydrophobic polyolefin film and a hydrophilic biobased film with different moisture sensitivities and then stored at temperatures of 20 40 degrees C and relative humidities (RH) of 60-100 %. The range of shelf life estimates varied greatly with product and was affected by the moisture and quality criteria limit values. In general, the temperature effect on shelf life was greater than that of humidity over the ranges examined. The magnitude of the difference in shelf life between moisture content and quality index used as criteria was greater with the less permeable hydrophobic polyolefin film. Accelerated shelf life testing at higher temperatures and humidities was shown to have a greater impact on the estimated shelf life when using specific quality criteria rather than moisture content. Use of moisture-sensitive packaging film accelerated deterioration compared to hydrophobic packaging film. The proposed comparative methodology is helpful for designing accelerated shelf life testing of dried foods.

关键词： Optimization   Neural networks   Evolutionary computation   Search problems   Computer science   Sociology   Statistics   Denoising autoencoder (DAE)   large-scale multiobjective optimization   Pareto-optimal subspace   restricted Boltzmann machine (RBM)   sparse Pareto-optimal solutions  

摘要： Due to the curse of dimensionality of search space, it is extremely difficult for evolutionary algorithms to approximate the optimal solutions of large-scale multiobjective optimization problems (LMOPs) by using a limited budget of evaluations. If the Pareto-optimal subspace is approximated during the evolutionary process, the search space can be reduced and the difficulty encountered by evolutionary algorithms can be highly alleviated. Following the above idea, this article proposes an evolutionary algorithm to solve sparse LMOPs by learning the Pareto-optimal subspace. The proposed algorithm uses two unsupervised neural networks, a restricted Boltzmann machine, and a denoising autoencoder to learn a sparse distribution and a compact representation of the decision variables, where the combination of the learnt sparse distribution and compact representation is regarded as an approximation of the Pareto-optimal subspace. The genetic operators are conducted in the learnt subspace, and the resultant offspring solutions then can be mapped back to the original search space by the two neural networks. According to the experimental results on eight benchmark problems and eight real-world problems, the proposed algorithm can effectively solve sparse LMOPs with 10000 decision variables by only 100000 evaluations.

关键词： Computer science   Search engines   Electronic mail   Databases   Computational intelligence   Biological system modeling   Recommender systems   Information retrieval   knowledge graph   matching theory   recommender system   stable matching  

摘要： Matching plays a vital role in the rational allocation of resources in many areas, ranging from market operation to people's daily lives. In economics, the term matching theory is coined for pairing two agents in a specific market to reach a stable or optimal state. In computer science, all branches of matching problems have emerged, such as the question-answer matching in information retrieval, user-item matching in a recommender system, and entity-relation matching in the knowledge graph. A preference list is the core element during a matching process, which can either be obtained directly from the agents or generated indirectly by prediction. Based on the preference list access, matching problems are divided into two categories, i.e., explicit matching and implicit matching. In this paper, we first introduce the matching theory's basic models and algorithms in explicit matching. The existing methods for coping with various matching problems in implicit matching are reviewed, such as retrieval matching, user-item matching, entity-relation matching, and image matching. Furthermore, we look into representative applications in these areas, including marriage and labor markets in explicit matching and several similarity-based matching problems in implicit matching. Finally, this survey paper concludes with a discussion of open issues and promising future directions in the field of matching.

关键词： Automated vehicle   Daily activities   On-board activities   Multitasking   Interactive survey   Multiple discrete-continuous extreme value   model  

摘要： Fully Automated Vehicles (AVs) have been widely expected to revolutionise the future travel experience. Recent studies have shown that their impact may also reach beyond the travel episode, and lead their users to alter other activities performed during the day - their daily lifestyles. This study is among the first to empirically investigate the changes that travellers expect in their daily activities with AVs. To this aim, we created an interactive stated activitytravel survey, in which respondents designed their current daily schedule and, following that, redesigned it while imagining that their most frequently used travel mode is replaced with an AV. We administered the survey to 509 commuters in the Netherlands and analysed (changes in) onboard and stationary activity patterns using the multiple discrete-continuous extreme value (MDCEV) model. Results show a clear increase in the prevalence of various on-board activities in the AV compared to current modes, and even stronger increase for the high income and higher educated groups. Changes in stationary activities are less pronounced: no changes in the aggregate, but some changes within particular socio-demographic groups. Specific changes in stationary activities were associated with specific changes in on-board activities for the higher educated respondents: switching to AVs, they were more likely than others to add on-board work, meals, and leisure to their trips and more likely to add a getting ready activity to their stationary schedules. This study contributes to the growing body of literature that recognises and models onboard activities as an integral part of daily schedules.

关键词： Task analysis   Decision making   Trajectory   Visualization   Deep learning   Data models   Computer science   Unmanned driving   deep learning   feature fusion   decision fusion  

摘要： Behavioral decision systems may suffer from poor performance due to the failure in capturing the vibrations of environmental information. To better capture such vibrations and then make more accurate predictions, a parallel deep neural network based on dual fusions including feature and decision is proposed, called DFFD-Net. DFFD-NET is composed of two parts, the feature fusion network and the driving data network. The feature fusion model adopts two different operations, deconvolution and linear weighting, to fuse local features and global features, respectively. Deconvolution is applied between the convolutional layers, while linear weighting is operated among the outputs of SPP and LSTM. To further improve the accuracy of the prediction, the decisions generated from both networks are further weighed to get the final decision. Experimentally, DFFD-NET is implemented in the benchmarks BDDV and TORCS, and the results show that the final performance is benefited from both feature fusion and decision fusion. From the comparison, DFFD-NET can get state-of-the-art results on both perplexity and precision by only using the images captured from the front-facing camera as well as a few sensing data.