The current velocity observation of LADCP(Lowered Acoustic Doppler Current Profiler)has the advantages of a large vertical range of observation and high operability compared with traditional current measurement method...
详细信息
The current velocity observation of LADCP(Lowered Acoustic Doppler Current Profiler)has the advantages of a large vertical range of observation and high operability compared with traditional current measurement methods,and is being widely used in the field of ocean *** and inverse methods are now commonly used by the international marine community to process LADCP data and calculate ocean current *** two methods have their advantages and *** shear method calculates the value of current shear more accurately,while the accuracy in an absolute value of the current is *** inverse method calculates the absolute value of the current velocity more accurately,but the current shear is less *** on the shear method,this paper proposes a layering shear method to calculate the current velocity profile by“layering averaging”,and proposes corresponding current calculation methods according to the different types of problems in several field observation data from the western Pacific,forming an independent LADCP data processing *** comparison results have shown that the layering shear method can achieve the same effect as the inverse method in the calculation of the absolute value of current velocity,while retaining the advantages of the shear method in the calculation of a value of the current shear.
This paper describes how the kinematic configuration of a driving simulator's motion system affects the rendered inertial motion. The specific force and rotational rate equations between the point where the motion...
This paper describes how the kinematic configuration of a driving simulator's motion system affects the rendered inertial motion. The specific force and rotational rate equations between the point where the motion is applied (Motion Reference Point (MRP)), and the point in which the driver perceives the motion (Cueing Reference Point (CRP)), are derived for three kinematic configurations: (i) a hexapod, (ii) a hexapod with an xy-drive and a yaw-drive below, and (iii) the same system as (ii), but with the yaw-drive on top. The rotational rate equations show that having a yaw-drive on top greatly complicates the motion control. Furthermore, simulation results show that, regardless of the yaw-drive location, the difference between MRP and CRP becomes noticeable for large yaw-drive excitations. For such driving simulators, the positional offset between MRP and CRP can therefore not be ignored, complicating the motion control.
Alzheimer’s disease(AD)is a progressive neurodegenerative disorder characterized by cognitive *** pathological hallmarks of AD include the deposition of b-amyloid(Ab)plaques,hyperphosphorylation of tau protein,synapt...
详细信息
Alzheimer’s disease(AD)is a progressive neurodegenerative disorder characterized by cognitive *** pathological hallmarks of AD include the deposition of b-amyloid(Ab)plaques,hyperphosphorylation of tau protein,synaptic loss,and reactive astrogliosis in the brain[1].As there is still no effective therapy for AD,the development of novel treatment strategies is imperative.
Roundabouts frequently present challenging traffic scenarios, often leading to accidents, making it crucial to design a safe and efficient automatic driving decision-making system for effective navigation. While deep ...
详细信息
ISBN:
(数字)9798331532093
ISBN:
(纸本)9798331532109
Roundabouts frequently present challenging traffic scenarios, often leading to accidents, making it crucial to design a safe and efficient automatic driving decision-making system for effective navigation. While deep reinforcement learning (DRL) has shown promise in this field, it faces challenges such as poor sample efficiency and safety concerns. To address these issues, this paper proposes a hybrid approach that combines DRL with heuristic rules. We introduce an action filter module that pre-screens the action space to select valid actions based on the strategy, thereby improving sample efficiency. Additionally, we propose a novel reward function that encourages vehicles to switch to the outer lane before exiting the roundabout. This function helps mitigate safety concerns and traffic congestion under varying vehicle densities, enhancing the robustness of the algorithm. The proposed method is tested in a two-lane roundabout scenario. Experimental results demonstrate that the action filter module significantly improves training speed and traffic safety, while the novel reward function enhances the adaptability and robustness of the model.
Many applications of location-based indoor navigation services require precise location information of a user. While Global Positioning System (GPS) loses reliability indoors, fingerprints-based localization technolog...
详细信息
A three-dimensional (3-D) printed lightweight microwave absorber design is presented in this work. The geometry uses a perforated honeycomb made from Polylactic acid (PLA) material as the constituent dielectric, thus ...
详细信息
ISBN:
(数字)9798350369908
ISBN:
(纸本)9798350369915
A three-dimensional (3-D) printed lightweight microwave absorber design is presented in this work. The geometry uses a perforated honeycomb made from Polylactic acid (PLA) material as the constituent dielectric, thus minimizing both the overall volume and weight of the structure. The unit cell geometry exhibits an absorption peak at 4.6 GHz with a peak absorptivity of 99.99%. The topology also shows polarization-insensitivity and angular stability. Further, the design has been investigated for planar as well as non-planar (cylindrical) surfaces, and its absorption performances are found satisfactory.
Fluorescent metal nanoparticles (MNPs) have garnered considerable interest in the realm of healthcare applications. Within this domain, we present a novel fluorescent sensor: Pamoic acid (PA) functionalized excitation...
详细信息
Fluorescent metal nanoparticles (MNPs) have garnered considerable interest in the realm of healthcare applications. Within this domain, we present a novel fluorescent sensor: Pamoic acid (PA) functionalized excitation-dependent gold nanoparticles (PA@AuNPs), designed to ascertain levofloxacin (LF) concentrations in human urine samples under pH 7.0 conditions. The synthesis of PA@AuNPs was achieved via a chemical reduction method employing PA as both a reducing and stabilizing agent. Validation of the successful synthesis of PA@AuNPs was conducted utilizing a suite of analytical techniques including X-ray diffraction (XRD), ultraviolet–visible absorption spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Microscopic examination via field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM) elucidated the spherical morphology of PA@AuNPs, with an average diameter ranging from 10 to 15 nm. Furthermore, atomic force microscopy (AFM) revealed an average surface roughness of 20.72 nm for PA@AuNPs. Thermal analysis results divulge that PA@AuNPs are highly stable up to 370 °C. The PA@AuNPs have shown more than 10-fold higher selectivity for LF in comparison with other commercially available antibiotics. The fluorescence emission intensity of PA@AuNPs (quantum yield (ΦF) 3.36 %) has shown enhanced redshift (436 → 497 nm;∼61 nm) (λex 353 nm) upon the sequential addition of LF (0 → 100 µM) and achieved a lower detection limit (LoD = 36 nM;LoQ = 121 nM;Ka = 1.0457 × 104 M−1) with increased ΦF 18.96 %. This radiative process and fluorescence enhancement were confirmed by time-correlated single photon counting (TCSPC) measurement (4.89 → 5.36 ns). Interestingly, upon sensing LF, PA@AuNPs changed their morphology from spherical to octahedron and displayed an excimer formation through intermolecular π-π stacking. Furthermore, the stability of the
IQ signals are a core technology of the zero-IF architecture in modern communication technology, but they are often unstable due to factors such as amplitude and phase imbalances. Utilizing the characteristics of IQ t...
详细信息
Cognitive errors made by pilots during flight missions may lead to decision-making mistakes, potentially causing safety accidents. Understanding the neural mechanisms underlying pilot cognition is crucial for enhancin...
详细信息
ISBN:
(数字)9798331510138
ISBN:
(纸本)9798331510145
Cognitive errors made by pilots during flight missions may lead to decision-making mistakes, potentially causing safety accidents. Understanding the neural mechanisms underlying pilot cognition is crucial for enhancing flight safety. This study analyzes the brain activity patterns at the micro-time scale during the cognitive process of pilots. Specifically, participants were asked to perform a task involving interface reading and select the correct answer based on the displayed content. A data-adaptive clustering method was used to extract Electroencephalogram (EEG) microstates, and changes in these microstates were analyzed in relation to correct and incorrect responses. The results show that when cognitive errors occur, the transition probability of microstates associated with the attention network increases by 86%, while the transition probability of microstates related to the language-visual network increases by 68%. This suggests that, in the case of cognitive errors, the brain activates the attention and language-visual networks to enhance the evaluation of the situation and external information, as well as the processing of language and visual inputs, in order to better correct errors and adjust cognitive strategies. These findings provide reference biomarkers for identifying cognitive errors in pilots.
Recently Interior Permanent Magnet Synchronous Motor (IPMSM) has been widely used in home appliances, trains, and automobiles. Additionally, Model Predictive Control (MPC) is recognized for its high responsiveness, an...
详细信息
暂无评论