Improving Crowded Object Detection via Copy-Paste

Crowdedness caused by overlapping among similar objects is a ubiquitous challenge in the field of 2D visual object detection. In this paper, we first underline two main effects of the crowdedness issue: 1) IoU-confidence correlation disturbances (ICD) and 2) confused de-duplication (CDD). Then we explore a pathway of cracking these nuts from the perspective of data augmentation. Primarily, a particular copy-paste scheme is proposed towards making crowded scenes. Based on this operation, we first design a "consensus learning" method to further resist the ICD problem and then find out the pasting process naturally reveals a pseudo "depth" of object in the scene, which can be potentially used for alleviating CDD dilemma. Both methods are derived from magical using of the copy-pasting without extra cost for hand-labeling. Experiments show that our approach can easily improve the state-of-the-art detector in typical crowded detection task by more than 2% without any bells and whistles. Moreover, this work can outperform existing data augmentation strategies in crowded scenario.Comment: Accepted by AAAI202

Elucidating the Synergic Effect in Nanoscale MoS\u3csub\u3e2\u3c/sub\u3e/TiO\u3csub\u3e2\u3c/sub\u3e Heterointerface for Na-Ion Storage

Interface engineering in electrode materials is an attractive strategy for enhancing charge storage, enabling fast kinetics, and improving cycling stability for energy storage systems. Nevertheless, the performance improvement is usually ambiguously ascribed to the “synergetic effect”, the fundamental understanding toward the effect of the interface at molecular level in composite materials remains elusive. In this work, a well-defined nanoscale MoS2/TiO2 interface is rationally designed by immobilizing TiO2 nanocrystals on MoS2 nanosheets. The role of heterostructure interface between TiO2 and MoS2 by operando synchrotron X-ray diffraction (sXRD), solid-state nuclear magnetic resonance, and density functional theory calculations is investigated. It is found that the existence of a hetero-interfacial electric field can promote charge transfer kinetics. Based on operando sXRD, it is revealed that the heterostructure follows a solid-solution reaction mechanism with small volume changes during cycling. As such, the electrode demonstrates ultrafast Na+ ions storage of 300 mAh g−1 at 10 A g−1 and excellent reversible capacity of 540 mAh g−1 at 0.2 A g−1. This work provides significant insights into understanding of heterostructure interface at molecular level, which suggests new strategies for creating unconventional nanocomposite electrode materials for energy storage systems

Sparse Representation of Brain Aging: Extracting Covariance Patterns from Structural MRI

An enhanced understanding of how normal aging alters brain structure is urgently needed for the early diagnosis and treatment of age-related mental diseases. Structural magnetic resonance imaging (MRI) is a reliable technique used to detect age-related changes in the human brain. Currently, multivariate pattern analysis (MVPA) enables the exploration of subtle and distributed changes of data obtained from structural MRI images. In this study, a new MVPA approach based on sparse representation has been employed to investigate the anatomical covariance patterns of normal aging. Two groups of participants (group 1∶290 participants; group 2∶56 participants) were evaluated in this study. These two groups were scanned with two 1.5 T MRI machines. In the first group, we obtained the discriminative patterns using a t-test filter and sparse representation step. We were able to distinguish the young from old cohort with a very high accuracy using only a few voxels of the discriminative patterns (group 1∶98.4%; group 2∶96.4%). The experimental results showed that the selected voxels may be categorized into two components according to the two steps in the proposed method. The first component focuses on the precentral and postcentral gyri, and the caudate nucleus, which play an important role in sensorimotor tasks. The strongest volume reduction with age was observed in these clusters. The second component is mainly distributed over the cerebellum, thalamus, and right inferior frontal gyrus. These regions are not only critical nodes of the sensorimotor circuitry but also the cognitive circuitry although their volume shows a relative resilience against aging. Considering the voxels selection procedure, we suggest that the aging of the sensorimotor and cognitive brain regions identified in this study has a covarying relationship with each other

FRACTURE SIMULATION ANALYSIS OF CONNECTING ROD ON DIESEL ENGINE

The connecting rod of high explosion pressure diesel engine was easily fatigue and fracture; the working dynamic load of connecting rod was obtained based on the multibody dynamics. And on this basis,the fatigue life danger zone was founded based on the dynamic stress recovery method,and fracture simulation was analyzed for the region. The results show that the operating cycles reduced from millions to ten thousand times after fatigue cracks taking place,so once the crack was founded,it was the best time to replace the connecting rod to avoid catastrophic accidents

phasediagrampredictionofsystemsmnno32mno3nh2omcamgandliwithmodifiedbetmodel

BET-model parameters for the binary system Mn(NO3 )2-H2 O were obtained by fitting experimental water activities at 298.15 K. The values obtained in this work were compared to those fitted previously for the systems Ca(NO3)2-H2O and Zn(NO3)2-H2O, showing reasonable agreement. With the model parameters fitted at 298 K,the vapor pressure of the saturated solution for the phases Mn(NO3 )2 · 6 H2 O and Mn(NO3 )2 · 4 H2 O were predicted and shows quite good agreement with the experimental values. The phase diagram of the Mn(NO2 )2-H2O system reproduced by the BET model shows smaller deviation from the experimental data than that by the extended UNIQUAC model. The ternary phase diagrams of the systems Me(NO3)n-Mn(NO3)2-H2O (Me= Mg, Ca and Li) are predicted with the binary model parameter and compared with available experimental data. The predicted eutectic compositions were given as possible heat storage materials

Apatite (U-Th)/He Thermochronological Constraints on the Landscape Evolution Linked to the Normal Faulting in Taishan Mountain, Eastern China

Taishan Mountain in the eastern China is a normal-fault-controlled range that formed during the Meso-Cenozoic, in response to large-scale extension and lithospheric thinning of the North China Craton. However, constraints on the timing of the polyphase extensional events which formed the Taishan edifice remain poorly resolved, hindering a detailed understanding of the landscape evolution of this prominent mountain. Here, we conducted apatite (U-Th)/He dating on sixteen samples from three profiles perpendicular in the Taishan Mountain, with a major view to control structures in Taishan Mountain and to resolve the Meso-Cenozoic landscape evolution. The newly determined apatite (U-Th)/He ages show a wide variation range of ~113 to 30 Ma, indicating a slow and protracted cooling history. The inverse thermal history modeling results reveal two pulses of enhanced cooling at ~80 to 60 and 55 to 50 Ma, which we interpret as exhumation related to normal fault activity. Furthermore, one-dimensional modeling indicates that the magnitude of tectonic exhumation is constrained at ≥15 m/Myr across the Yunbuqiao, Zhongtianmen, and Taishan Piedmont faults. Integrating this study and published studies, we suggest that Taishan Mountain underwent four-stage evolution since 100 Ma: (1) the whole Taishan Mountain commenced a continuous and slow exhumation under a weaker tensional environment at ~100 to 80 Ma, (2) the joint growth and interactions within a normal fault system resulted in rapid uplift and promoted the formation of the Proto-Taishan Mountain at ~80 to 60 Ma, (3) the Taishan Mountain underwent exhumation at ~55 to 50 Ma, interpreted as a tectonic response to the Taishan Piedmont Fault, and (4) the last stage (~50 to 0 Ma), the Taishan Mountain experienced protracted exhumation related to normal faulting until now. We attribute the extensive normal faulting to the subduction and slab rollback of the Izanagi-Pacific Plates, which shaped the present-day geomorphology of Taishan Mountain

Lifespan Development of the Human Brain Revealed by Large-Scale Network Eigen-Entropy

Imaging connectomics based on graph theory has become an effective and unique methodological framework for studying functional connectivity patterns of the developing and aging brain. Normal brain development is characterized by continuous and significant network evolution through infancy, childhood, and adolescence, following specific maturational patterns. Normal aging is related to some resting state brain networks disruption, which are associated with certain cognitive decline. It is a big challenge to design an integral metric to track connectome evolution patterns across the lifespan, which is to understand the principles of network organization in the human brain. In this study, we first defined a brain network eigen-entropy (NEE) based on the energy probability (EP) of each brain node. Next, we used the NEE to characterize the lifespan orderness trajectory of the whole-brain functional connectivity of 173 healthy individuals ranging in age from 7 to 85 years. The results revealed that during the lifespan, the whole-brain NEE exhibited a significant non-linear decrease and that the EP distribution shifted from concentration to wide dispersion, implying orderness enhancement of functional connectome over age. Furthermore, brain regions with significant EP changes from the flourishing (7–20 years) to the youth period (23–38 years) were mainly located in the right prefrontal cortex and basal ganglia, and were involved in emotion regulation and executive function in coordination with the action of the sensory system, implying that self-awareness and voluntary control performance significantly changed during neurodevelopment. However, the changes from the youth period to middle age (40–59 years) were located in the mesial temporal lobe and caudate, which are associated with long-term memory, implying that the memory of the human brain begins to decline with age during this period. Overall, the findings suggested that the human connectome shifted from a relatively anatomical driven state to an orderly organized state with lower entropy

Study on seismic response of a new staggered story isolated structure considering SSI effect

The new staggered story isolated structure is a new type of seismic isolated structure developed from base isolated structure and inter-story isolated structure. In order to explore the seismic response of the new staggered story isolated structure considering the soil-structure interaction (SSI), the model of a new staggered story isolated structure considering SSI effect is established to analyze the nonlinear dynamic time-history response under rare earthquakes, and the comparison between hard soil and soft soil was carried out. Results show that the stiffness of the new staggered story isolated structure reduced, the modal period extended and the seismic response reduced by considering the SSI effect, the softer the site soil, the more obvious those changes are. Meanwhile, the shear force and the damage of the core tube decreases, while the shear force and the damage of the frame increases, the shear force transfers from the core tube to the frame. Additionally, the energy absorption of the seismic isolated bearings at the frame reduced, the energy absorption of the seismic isolated bearings at the core tube increased, the softer the site soil, the more obvious the trend is

Combining Resting-state fMRI and DTI Analysis for Early-onset Schizophrenia

We combined measures of resting-state functional magnetic resonance imaging and diffusion tensor imaging (DTI) to investigate alterations of function-structure relationships in patients with early-onset schizophrenia. DTI analysis revealed reduced fractional anisotropy in right frontal white matter. Corresponding gray matter regions showed reduced functional connectivity with other regions in the brain in patients with early-onset schizophrenia, compared with healthy controls. Our results demonstrated abnormal function-structure relationships in early-onset schizophrenia, and supported the view that white matter lesions might disrupt the neural circuits between frontal regions and other brain regions, and affect the functional connectivity in the frontal cortex