Internet Adoption Trends during COVID-19

This paper examines the common perception that internet adoption accelerated globally during the COVID- 19 pandemic. The data show little evidence of a faster expansion of access to internet (extensive margin) across all country income groups but strong evidence of acceleration in the improvement in the quality of connectivity (intensive margin). The data also support that, despite a decline in internet prices over the past decade, affordability of digital services remains a concern for low-income developing countries

FREPA: An Automated and Formal Approach to Requirement Modeling and Analysis in Aircraft Control Domain

Formal methods are promising for modeling and analyzing system requirements. However, applying formal methods to large-scale industrial projects is a remaining challenge. The industrial engineers are suffering from the lack of automated engineering methodologies to effectively conduct precise requirement models, and rigorously validate and verify (V&V) the generated models. To tackle this challenge, in this paper, we present a systematic engineering approach, named Formal Requirement Engineering Platform in Aircraft (FREPA), for formal requirement modeling and V\&V in the aerospace and aviation control domains. FREPA is an outcome of the seamless collaboration between the academy and industry over the last eight years. The main contributions of this paper include 1) an automated and systematic engineering approach FREPA to construct requirement models, validate and verify systems in the aerospace and aviation control domain, 2) a domain-specific modeling language AASRDL to describe the formal specification, and 3) a practical FREPA-based tool AeroReq which has been used by our industry partners. We have successfully adopted FREPA to seven real aerospace gesture control and two aviation engine control systems. The experimental results show that FREPA and the corresponding tool AeroReq significantly facilitate formal modeling and V&V in the industry. Moreover, we also discuss the experiences and lessons gained from using FREPA in aerospace and aviation projects.Comment: 12 pages, Published by FSE 202

Effects of virtual exposure to urban greenways on mental health

Urban greenways (UGW) are increasingly recognized as vital components of urban green infrastructure (UGI). While existing research has provided empirical evidence on the positive impacts of UGW on physical health, studies focusing on the effects on mental health remain limited. Moreover, previous investigations predominantly compare UGW as a whole with other built environments, neglecting the influence of specific vegetation designs along UGW on mental health. To address this research gap, we conducted a randomized controlled experiment to examine the impact of vegetation design along UGW on stress reduction and attention restoration. A total of 94 participants were randomly assigned to one of four UGW conditions: grassland, shrubs, grassland and trees, or shrubs and trees. Utilizing immersive virtual reality (VR) technology, participants experienced UGW through a 5-min video presentation. We measured participants’ subjective and objective stress levels and attentional functioning at three time-points: baseline, pre-video watching, and post-video watching. The experimental procedure lasted approximately 40 minutes. Results of the repeated-measures ANOVA revealed that participants experienced increased stress and mental fatigue after the stressor and decreased levels following the UGW intervention. Furthermore, between-group analyses demonstrated that the shrubs group and the grassland and trees group exhibited significantly greater stress reduction than the grassland group. However, there are no significant differences in attention restoration effects between the four groups. In conclusion, virtual exposure to UGW featuring vegetation on both sides positively affected stress reduction and attention restoration. It is recommended that future UGW construction incorporates diverse vegetation designs, including shrubs or trees, instead of solely relying on grassland. More research is needed to explore the combined effects of shrubs and trees on mental health outcomes

Pathological demand avoidance: my thoughts on looping effects and commodification of autism

Hacking suggests autism is a human kind, and has used autism to discuss their evolution over time. Looping effects caused the autism human kind to evolve since 1995, with people identifying with the autism human kind, and the commodification of the autism human kind by the autism industry. Pathological demand avoidance (PDA) was created from the looping effects controlled by the autism industry. This has undermined autism self-advocacy by supporting the medical paradigm of the autism human kind. By refusing to engage with PDA, people of the autism human kind limit the commodification of autism; creating greater emancipation

Effect of WC particles preparation method on microstructure and properties of laser cladded Ni60-WC coatings

Ni60 and WC composite coatings were prepared on 17-4PH martensitic stainless steel with 30 wt% agglomeration-sintering WC (AS-WC) or 30 wt% sintering-crushing WC (SC-WC) respectively. The results show that in the AS-WC doped coating, the WC particles are more easily melted and dispersed, and a large amount of acicular (Fe, Ni, W)23C6 carbides are dispersed throughout the coating. However, in the SC-WC doped coating, the melting is quite limited and only occurs at the outer edge of the WC particles, and a small amount of (Fe, Ni, W)23C6 precipitated in the coating. Owing to this microstructure difference, the AS-WC doped coating possesses higher hardness, the microhardness reached 622.27 HV0.2 which is 25.5% higher than the normal Ni60 coating without WC, and 10.0% higher than the SC-WC doped coating. Moreover, the wear resistance test results indicate that the AS-WC doped coating has the best wear resistance compared to the SC-WC doped coating and normal Ni60 coating without WC. Those findings help us to obtain better Ni-based high hardness coatings for industrial applications

A new method for examining the co-occurrence network of fossil assemblages

Abstract Currently, studies of ancient faunal community networks have been based mostly on uniformitarian and functional morphological evidence. As an important source of data, taphonomic evidence offers the opportunity to provide a broader scope for understanding palaeoecology. However, palaeoecological research methods based on taphonomic evidence are relatively rare, especially for body fossils in lacustrine sediments. Such fossil communities are not only affected by complex transportation and selective destruction in the sedimentation process, they also are strongly affected by time averaging. Historically, it has been believed that it is difficult to study lacustrine entombed fauna by a small-scale quadrat survey. Herein, we developed a software, the TaphonomeAnalyst, to study the associational network of lacustrine entombed fauna, or taphocoenosis. TaphonomeAnalyst allows researchers to easily perform exploratory analyses on common abundance profiles from taphocoenosis data. The dataset for these investigations resulted from fieldwork of the latest Middle Jurassic Jiulongshan Formation near Daohugou Village, in Ningcheng County of Inner Mongolia, China, spotlighting the core assemblage of the Yanliao Fauna. Our data included 27,000 fossil specimens of animals from this deposit, the Yanliao Fauna, whose analyses reveal sedimentary environments, taphonomic conditions, and co-occurrence networks of this highly studied assemblage, providing empirically robust and statistically significant evidence for multiple Yanliao habitats