158 research outputs found

    Optical-Fiber-Based Smart Concrete Thermal Integrity Profiling: An Example of Concrete Shaft

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    Concrete is currently the most widely used construction material in the world. The integrity of concrete during the pouring process could greatly affect its engineering performance. Taking advantage of heat production during the concrete curing process, we propose an optical-fiber-based thermal integrity profiling (TIP) method which can provide a comprehensive and accurate evaluation of the integrity of concrete immediately after its pouring. In this paper, we use concrete shaft as an example to conduct TIP by using the optical fiber as a temperature sensor which can obtain high spatial resolution temperature data. Our method is compared with current thermal infrared probe or embedded thermal sensor-based TIP for the concrete shaft. This innovation makes it possible to detect defects inside of the concrete shaft with thorough details, including size and location. First, we establish a 3D shaft model to simulate temperature distribution of concrete shaft. Then, we extract temperature distribution data at the location where the optical fiber would be installed. Based on the temperature distribution data, we reconstruct a 3D model of the concrete shaft. Evaluation of the concrete integrity and the existence of the potential defect are shown in the paper. Overall, the optical-fiber-based TIP method shows a better determination of defect location and size

    Air Bumper: A Collision Detection and Reaction Framework for Autonomous MAV Navigation

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    Autonomous navigation in unknown environments with obstacles remains challenging for micro aerial vehicles (MAVs) due to their limited onboard computing and sensing resources. Although various collision avoidance methods have been developed, it is still possible for drones to collide with unobserved obstacles due to unpredictable disturbances, sensor limitations, and control uncertainty. Instead of completely avoiding collisions, this article proposes Air Bumper, a collision detection and reaction framework, for fully autonomous flight in 3D environments to improve the safety of drones. Our framework only utilizes the onboard inertial measurement unit (IMU) to detect and estimate collisions. We further design a collision recovery control for rapid recovery and collision-aware mapping to integrate collision information into general LiDAR-based sensing and planning frameworks. Our simulation and experimental results show that the quadrotor can rapidly detect, estimate, and recover from collisions with obstacles in 3D space and continue the flight smoothly with the help of the collision-aware map. Our Air Bumper will be released as open-source software on GitHub

    La giuridificazione del canone dell'efficienza della pubblica amministrazione

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    Differentially expressed antioxidant genes. The genes were manually summarized by reviewing GO and NR annotation. (XLSX 14 kb

    Effect of Deoxynivalenol Contamination on the Safety, Quality Indexes and Utilization Rate of Wheat

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    In this study, 17 deoxynivalenol (DON) contaminated wheat samples were assessed for safety and quality index such as unit weight, water absorption of gluten, crude protein content, unsound kernel content, sprouted kernel content, gibberella damaged kernel content and insect infested kernel content as well as the pollution status of DON and heavy metals. Furthermore, the relationship between the content of DON in wheat grains and other parameters was analyzed. The impact of the processing of gluten and starch in the break and reduction systems on the level of DON contamination was examined. The results showed that the pollution level of DON in wheat samples had a good linear correlation with unit weight, water absorption of gluten, crude protein content, unsound kernel content, sprouted kernel content, gibberella damaged kernel content and insect infested kernel content. The correlation between gluten water absorption and the content of DON was not significant, indicating that DON content could not affect the storage quality of wheat. Additionally, it was found that the heavy metals As and Cd as well as the elements Ca and P were not significantly correlated with DON content, but only Ca in whole wheat flour was correlated with the content of DON. The levels of DON in gluten and starch from the break and reduction systems, respectively were both lower than 200 µg/kg, indicating that wheat with DON over-standard can be used commercially for the preparation of gluten or starch

    Contribution of basal ganglia activity to REM sleep disorder in Parkinson’s disease

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    Background: Rapid eye movement (REM) sleep behaviour disorder (RBD) is one of the most common sleep problems and represents a key prodromal marker in Parkinson’s disease (PD). It remains unclear whether and how basal ganglia nuclei, structures that are directly involved in the pathology of PD, are implicated in the occurrence of RBD. Method: Here, in parallel with whole-night video polysomnography, we recorded local field potentials from two major basal ganglia structures, the globus pallidus internus and subthalamic nucleus, in two cohorts of patients with PD who had varied severity of RBD. Basal ganglia oscillatory patterns during RBD and REM sleep without atonia were analysed and compared with another age-matched cohort of patients with dystonia that served as controls. Results: We found that beta power in both basal ganglia nuclei was specifically elevated during REM sleep without atonia in patients with PD, but not in dystonia. Basal ganglia beta power during REM sleep positively correlated with the extent of atonia loss, with beta elevation preceding the activation of chin electromyogram activities by ~200 ms. The connectivity between basal ganglia beta power and chin muscular activities during REM sleep was significantly correlated with the clinical severity of RBD in PD. Conclusions: These findings support that basal ganglia activities are associated with if not directly contribute to the occurrence of RBD in PD. Our study expands the understanding of the role basal ganglia played in RBD and may foster improved therapies for RBD by interrupting the basal ganglia-muscular communication during REM sleep in PD
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