An open-source cold-formed steel connection test database to support future data models

A data structure and physical test database are implemented for cold-formed steel connections. The database is publicly available on GitHub in a format that is both human-readable and machine-readable. The data structure is designed to accommodate connection tests with varying test variables including fastener type, quantity of fasteners in a specimen, and the number and type of plies. The database design is made compatible with open-source software tooling to support future data-driven model development. Strategies are discussed for encouraging general user adoption of open-source databases and software including education, community guidelines, and easy-to-use interfaces

A real-time dynamic obstacle tracking and mapping system for UAV navigation and collision avoidance with an RGB-D camera

The real-time dynamic environment perception has become vital for autonomous robots in crowded spaces. Although the popular voxel-based mapping methods can efficiently represent 3D obstacles with arbitrarily complex shapes, they can hardly distinguish between static and dynamic obstacles, leading to the limited performance of obstacle avoidance. While plenty of sophisticated learning-based dynamic obstacle detection algorithms exist in autonomous driving, the quadcopter's limited computation resources cannot achieve real-time performance using those approaches. To address these issues, we propose a real-time dynamic obstacle tracking and mapping system for quadcopter obstacle avoidance using an RGB-D camera. The proposed system first utilizes a depth image with an occupancy voxel map to generate potential dynamic obstacle regions as proposals. With the obstacle region proposals, the Kalman filter and our continuity filter are applied to track each dynamic obstacle. Finally, the environment-aware trajectory prediction method is proposed based on the Markov chain using the states of tracked dynamic obstacles. We implemented the proposed system with our custom quadcopter and navigation planner. The simulation and physical experiments show that our methods can successfully track and represent obstacles in dynamic environments in real-time and safely avoid obstacles

A vision-based autonomous UAV inspection framework for unknown tunnel construction sites with dynamic obstacles

Tunnel construction using the drill-and-blast method requires the 3D measurement of the excavation front to evaluate underbreak locations. Considering the inspection and measurement task's safety, cost, and efficiency, deploying lightweight autonomous robots, such as unmanned aerial vehicles (UAV), becomes more necessary and popular. Most of the previous works use a prior map for inspection viewpoint determination and do not consider dynamic obstacles. To maximally increase the level of autonomy, this paper proposes a vision-based UAV inspection framework for dynamic tunnel environments without using a prior map. Our approach utilizes a hierarchical planning scheme, decomposing the inspection problem into different levels. The high-level decision maker first determines the task for the robot and generates the target point. Then, the mid-level path planner finds the waypoint path and optimizes the collision-free static trajectory. Finally, the static trajectory will be fed into the low-level local planner to avoid dynamic obstacles and navigate to the target point. Besides, our framework contains a novel dynamic map module that can simultaneously track dynamic obstacles and represent static obstacles based on an RGB-D camera. After inspection, the Structure-from-Motion (SfM) pipeline is applied to generate the 3D shape of the target. To our best knowledge, this is the first time autonomous inspection has been realized in unknown and dynamic tunnel environments. Our flight experiments in a real tunnel prove that our method can autonomously inspect the tunnel excavation front surface.Comment: 8 pages, 8 figure

An open-source cold-formed steel connection test database to support future data models

A data structure and physical test database are implemented for cold-formed steel connections. The database is publicly available on GitHub in a format that is both human-readable and machine-readable. The data structure is designed to accommodate connection tests with varying test variables including fastener type, quantity of fasteners in a specimen, and the number and type of plies. The database design is made compatible with open-source software tooling to support future data-driven model development. Strategies are discussed for encouraging general user adoption of open-source databases and software including education, community guidelines, and easy-to-use interfaces

The Combination of Low-Temperature Plasma and <i>Tripterygium wilfordii Hook F</i> on Ameliorating Imiquimod-Induced Psoriasiform Dermatitis in Mice

Improving the transdermal delivery efficiency of medicine is a crucial measure to improve the treatment efficiency of psoriasis. This paper developed a low-cost, highly active, and large-action-area low-temperature plasma (LTP) jet array. The two components of plasma—the high concentration of reactive oxygen and nitrogen species and the strong electric field—easily changed the structural integrity of the stratum corneum, which enhanced the transdermal delivery of the medicine. Tripterygium wilfordii Hook F (TwHF) is a medicine used to treat autoimmune and inflammatory conditions. The enhanced transdermal delivery of TwHF significantly alleviated the severed psoriasiform dermatitis induced by the imiquimod. Unlike the TwHF treatment alone, the LTP + TwHF treatment was more efficient at suppressing epidermal thickening and inhibiting systemic inflammation without noticeable side effects. LTP + TwHF treatment provides a potential new solution for psoriasis treatment

Spatiotemporal Joint Cleaning of Distribution Network Measurement Data Based on Correntropy Criterion with Variable Center Unscented Kalman Filter

Measurement data cleaning is a key step of edge computing in a distribution network; it is beneficial to improve the state perception and regional autonomy level of a distribution network. According to the temporal and spatial correlation of measurement data in the distribution network, a joint cleaning method of measurement data in a distribution network is proposed based on the correntropy criterion with variable center unscented Kalman filter (CC-VC-UKF). Initially, the mean square error (MSE) in the original unscented Kalman filter (UKF) is replaced by the correntropy criterion with variable center (CC-VC) to improve the accuracy of filtering the measurement data in the distribution network with a non-Gaussian non-zero mean measurement deviation. Then, the measured data of different measuring devices located on the same section of the line are filtered based on the CC-VC-UKF algorithm according to their respective reference time series to improve the signal-to-noise ratio of the measured data. Then, the filtered measured data are filtered and cleaned based on the CC-VC-UKF algorithm according to the space&ndash;time joint filtering and cleaning technology. Finally, the method is used to test the measurement data of the distribution network obtained by a power supply company in a city in north China to solve the problem of measurement deviation caused by the existence of space distance. Results show that this method can obtain FTU measurement data with higher precision from network topology based on the filtered TTU measurement data through the media of filtered spatial measurement deviation

Atmospheric-pressure non-equilibrium plasmas for effective abatement of pathogenic biological aerosols

The COVID-19, viral influenza, tuberculosis, and other widespread infectious diseases evidence that pathogenic biological aerosols (PBAs) are a serious threat to public health. Different from traditional inactivation methods, such as ultraviolet (UV) light which are only safe to use when people are not present, and high-efficiency particulate filters (HEPA) which merely filter microbes without killing them, atmospheric pressure nonequilibrium plasma (APNP) has shown its tremendous potential in drastically diminishing the aerosol transmission route of the infectious agents through the abatement of PBAs. The key issues to develop high performance APNP based air purification system are critically reviewed. Systematic studies on the hazards of different PBAs and the spread of PBAs in indoor environments guide the development of APNP sources to control communicable diseases. The key six sampling and seven detection methods on PBAs are introduced to analyze the PBA abatement efficiency by APNP. Seven common APNP sources which can remove viruses and bacteria aerosols efficiently developed during the past 8 years are introduced. For the APNP sources with small plasma volume, the electric field and diffusion driven charging are the dominant mechanisms to charge PBAs, while the common methods of dusty plasma research can be adapted to atmospheric-pressure conditions to describe the charging effects of APNP sources with large plasma volume. Plentiful long- and short-lifetime reactive oxygen and nitrogen species (RONS) generated by APNP effectively contribute to inactivation of bacterial aerosols. Current studies suggest that viral aerosols are mainly inactivated by short-lifetime RONS including 1O2, ONOO- and ONOOH. The study on the dissolution and reaction of gaseous RONS in microdroplets and accurate measurements on the evolution of charged PBAs are envisaged to be the focus of future research. Opportunities for multidisciplinary collaborative research to advance the development of next-generation high-performance plasma-based air purifiers are highlighted. </p

Evaluation of unimodal and multimodal information in health communication on GGO-related lung cancer screening: An eye-tracking study

Aims: To find out a better propaganda and education plan for the popularization of the ground-glass opacities-related (GGO-related) lung cancer screening.Methods and Material: The control group took a lung cancer screening knowledge test directly before receiving the health education. By contrast, the experimental group took the same knowledge test after receiving health education. This study designed unimodal and multimodal materials about GGO-related lung cancer. The text and graph were considered unimodal information, while the video was multimodal information. According to the different information forms they were exposed to, the experimental group was further divided into text, graphic, and video groups. An eye-tracking system was performed to record eye-tracking data synchronously.Results: Compared with the control group, the knowledge test scores of each experimental group were remarkably improved. Furthermore, the graphic group had a significantly higher correct rate on the No. 7 question, while the video group had the lowest. In terms of saccades, the video group had significantly higher speed and amplitude of saccades than the other two groups. In terms of fixation, the interval duration, total duration of whole fixations, and a number of whole fixations of the graphic group were significantly lower than those of the other two groups, while the video group had the highest values for these variables.Conclusions: It was on the unimodal information, such as text and graphics, that people can spend less time and cost to achieve effective acquisition of GGO-related lung cancer screening knowledge

The proportion of spreading ramet out of the total number of ramets (mean ± SE, N = 8) in <i>Carex brevicuspis</i> growing at two burial depths and three <i>Polygonum hydropiper</i> densities.

<p>Different letters indicate significant differences among treatments at the 0.05 significance level.</p

Summary of two-way ANOVA analyses for biomass accumulation, RNE, biomass allocation, number of ramets, ramet proportions, and spacer length of <i>C</i>. <i>brevicuspis</i> under different competition and burial depth treatments (F-values).

<p>^NS<i>P</i> ≥ 0.05;</p><p>* <i>P</i> < 0.05;</p><p>** <i>P</i> < 0.01;</p><p>*** <i>P</i> < 0.001.</p><p>Summary of two-way ANOVA analyses for biomass accumulation, RNE, biomass allocation, number of ramets, ramet proportions, and spacer length of <i>C</i>. <i>brevicuspis</i> under different competition and burial depth treatments (F-values).</p