62 research outputs found
A Novel Perception and Semantic Mapping Method for Robot Autonomy in Orchards
In this work, we propose a novel framework for achieving robotic autonomy in
orchards. It consists of two key steps: perception and semantic mapping. In the
perception step, we introduce a 3D detection method that accurately identifies
objects directly on point cloud maps. In the semantic mapping step, we develop
a mapping module that constructs a visibility graph map by incorporating
object-level information and terrain analysis. By combining these two steps,
our framework improves the autonomy of agricultural robots in orchard
environments. The accurate detection of objects and the construction of a
semantic map enable the robot to navigate autonomously, perform tasks such as
fruit harvesting, and acquire actionable information for efficient agricultural
production
New Interpretations of Normalization Methods in Deep Learning
In recent years, a variety of normalization methods have been proposed to
help train neural networks, such as batch normalization (BN), layer
normalization (LN), weight normalization (WN), group normalization (GN), etc.
However, mathematical tools to analyze all these normalization methods are
lacking. In this paper, we first propose a lemma to define some necessary
tools. Then, we use these tools to make a deep analysis on popular
normalization methods and obtain the following conclusions: 1) Most of the
normalization methods can be interpreted in a unified framework, namely
normalizing pre-activations or weights onto a sphere; 2) Since most of the
existing normalization methods are scaling invariant, we can conduct
optimization on a sphere with scaling symmetry removed, which can help
stabilize the training of network; 3) We prove that training with these
normalization methods can make the norm of weights increase, which could cause
adversarial vulnerability as it amplifies the attack. Finally, a series of
experiments are conducted to verify these claims.Comment: Accepted by AAAI 202
The Representation of Mosuo People and Mosuo Culture in Chinese Tourism Websites
Past research has shown that because tourism itself is a product of a gendered society, its processes are gendered in terms of construction, presentation, and consumption. This study examines how these websites shape the image of the Mosuo people and the Mosuo culture by analyzing texts in Chinese tourism websites. Ten representative Chinese tourism websites were selected for this study, and all relevant texts that could be retrieved were analyzed manually. All samples selected were officially published and represent only the attitudes of the tourism websites. The results of the study show that there are a large number of feminized or sexualized descriptions in the texts about the Mosuo people and the Mosuo culture provided by Chinese tourism websites. The language used on tourism websites is shaped by discourses of patriarchy and sexuality and is intended for heterosexual male tourists
Intracranial electrophysiological recordings on a swine model of mesial temporal lobe epilepsy
ObjectiveTo test the feasibility and reliability of intracranial electrophysiological recordings in an acute status epilepticus model on laboratory swine.MethodIntrahippocampal injection of kainic acid (KA) was performed on 17 male Bama pigs (Sus scrofa domestica) weighing between 25 and 35 kg. Two stereoelectroencephalography (SEEG) electrodes with a total of 16 channels were implanted bilaterally along the sensorimotor cortex to the hippocampus. Brain electrical activity was recorded 2 h daily for 9–28 days. Three KA dosages were tested to evaluate the quantities capable of evoking status epilepticus. Local field potentials (LFPs) were recorded and compared before and after the KA injection. We quantified the epileptic patterns, including the interictal spikes, seizures, and high-frequency oscillations (HFOs), up to 4 weeks after the KA injection. Test–retest reliability using intraclass correlation coefficients (ICCs) were performed on interictal HFO rates to evaluate the recording stability of this model.ResultsThe KA dosage test suggested that a 10 μl (1.0 μg/μl) intrahippocampal injection could successfully evoke status epilepticus lasting from 4 to 12 h. At this dosage, eight pigs (50% of total) had prolonged epileptic events (tonic-chronic seizures + interictal spikes n = 5, interictal spikes alone n = 3) in the later 4 weeks of the video-SEEG recording period. Four pigs (25% of total) had no epileptic activities, and another four (25%) had lost the cap or did not complete the experiments. Animals that showed epileptiform events were grouped as E + (n = 8) and the four animals showing no signs of epileptic events were grouped as E– (n = 4). A total of 46 electrophysiological seizures were captured in the 4-week post-KA period from 4 E + animals, with the earliest onset on day 9. The seizure durations ranged from 12 to 45 s. A significant increase of hippocampal HFOs rate (num/min) was observed in the E+ group during the post-KA period (weeks 1, 2,4, p < 0.05) compared to the baseline. But the E-showed no change or a decrease (in week 2, p = 0.43) compared to their baseline rate. The between-group comparison showed much higher HFO rates in E + vs. E – (F = 35, p < 0.01). The high ICC value [ICC (1, k) = 0.81, p < 0.05] quantified from the HFO rate suggested that this model had a stable measurement of HFOs during the four-week post-KA periods.SignificanceThis study measured intracranial electrophysiological activity in a swine model of KA-induced mesial temporal lobe epilepsy (mTLE). Using the clinical SEEG electrode, we distinguished abnormal EEG patterns in the swine brain. The high test–retest reliability of HFO rates in the post-KA period suggests the utility of this model for studying mechanisms of epileptogenesis. The use of swine may provide satisfactory translational value for clinical epilepsy research
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