Apparent Feature Research Articles

Recognition and quantification of apparent damage to concrete structure based on computer vision

To solve the problems of poor recognition of apparent concrete damage and the difficulty of efficient quantitative characterization of the damage parameters, this study proposes a damage detection method that integrates the target localization algorithm and the quantitative characterization algorithm of the damage based on computer vision. This paper proposes a YOLO v5-RS network combining Res2Net and SimAM to solve the problem of indistinctive apparent damage feature. The damage is segmented by image processing, and the crack and crush damage quantification method are proposed. The results show that compared with YOLO v5, the mAP and F1 of YOLO V5-RS are improved by 8.4% and 0.07, respectively, which indicates that the recognition of apparent structural damage has high robustness. To verify the recognition method’s generalization ability and the characterization method’s accuracy, four cases of different scale are introduced in this paper.

The LAMB3-EGFR signaling pathway mediates synergistic Anti-Cancer effects of berberine and emodin in Pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy, primarily due to the intrinsic development of chemoresistance. The most apparent histopathological feature associated with chemoresistance is the alterations in extracellular matrix (ECM) proteins. Natural dietary botanicals such as berberine (BBR) and emodin (EMO) have been shown to possess chemo-preventive potential by regulating ECM in various cancers. Herein, we further investigated the potential synergistic effects of BBR and EMO in enhancing anticancer efficacy by targeting ECM proteins in pancreatic cancer. Genomewide transcriptomic profiling identified that LAMB3 was significantly upregulated in PDAC tissue and highly associated with poor overall survival (OS, hazard ratio [HR], 2.99, 95 % confidence interval [CI], 1.46–6.15; p = 0.003) and progress-free survival (PFS, HR, 2.59; 95 % CI, 1.30–5.18; p = 0.007) in PDAC. A systematic series of functional experiments in BxPC-3 and MIA-PaCa-2 cells revealed that the combination of BBR and EMO exhibited synergistic anti-tumor potential, as demonstrated by cell proliferation, clonogenicity, migration, and invasion assays (p < 0.05–0.001). The combination also altered the expression of key proteins involved in apoptosis, EMT, and EGFR/ERK1,2/AKT signaling. These findings were further supported by patient-derived organoids (PDOs), where the combined treatment resulted in fewer and smaller organoids compared to each compound individually (p < 0.05–0.001). Our results suggest that BBR combined with EMO exerts synergistic anti-cancer effects by modulating the EGFR-signaling pathway through interference with LAMB3 in PDAC.

Investigation of typical behavioral characteristics of the dynamic separation of bauxite using vibration table tests

With the Bulk Jupiter accident, the dynamic separation behavior of solid bulk cargoes in sea transportation, which is different from the usual liquefaction of cargoes, has gradually come to people’s attention and is an almost empty field that urgently needs to be researched. In this work, we first conducted vibration table tests for bauxite, replaced bauxite with transparent soil with the same particle size distribution and moisture content, and combined image processing and analysis techniques to complete the detailed visualization of the dynamic separation process. Through the above research, this article reveals the essential characteristics of dynamic separation, including the changing rules of layer-wise water content, pore water pressure, particle motion, and pore water migration. It is concluded that the most apparent feature of the dynamic separation process is the generation of a free liquid surface containing fine particles in the upper layer. The article concludes with a systematic study of the dynamic separation of typical mineral soil. The novel experimental system developed in this study contributes to elucidating the mechanism of dynamic separation of minerals and soil from a precise perspective.

The Retroflex Sound of Languages Spoken in Southeast Tibet: Feature Floating, Feature Recombination and Its Historical Typological Value

In Southeast Tibet, some Tibeto-Burman languages have apparent retroflex feature floating. Some initial research on this phenomenon shows that different sound categories, such as a post consonant r and retroflex vowels (or finals), are not totally independent. This feature is likely the result of the evolution of one sound category toward another, and the evolution mechanism is the feature recombination between r and the basic consonant. This research approach can be applied to studying the whole Sino-Tibetan historical typology, including Chinese and Tibeto-Burman languages.

Crustal structure of the Tibetan Plateau and adjacent areas revealed from ambient noise tomography

How the Tibetan Plateau deformed in the Indian-Eurasian continental collision has been long debated, more specifically, over the relationship between the deep processes and surface structural complexity. Here, we use ambient noise tomography to obtain a high-resolution crustal S-wave velocity model beneath the Tibetan Plateau and adjacent areas involving a comprehensive dataset from over 500 stations. Our images reveal that the crustal flow should be in a limited scale according to the intermittent low-velocity zones (LVZs) observed in the middle crust at 20–40-km depth of the Tibetan Plateau. The distributions and strengths of LVZs further imply that different deep processes promote the surface deformation in various regions of the Tibetan Plateau. The LVZs in the northern plateau, collocated potassic magmatism and low velocity anomalies in the upper mantle, should be originated from the lithospheric delamination. However, in the southern plateau, the S-wave velocity showed an apparent lateral segmentation feature correlated with the north–south trending rifts. The feature indicates that the LVZs were likely controlled by the lateral tearing of the subducted Indian mantle lithosphere, which promotes the rifting deformation. Moreover, the LVZ in the central Tibet should have contributed to the formation of the conjugate strike-slip fault system. In the Tarim Basin, our model showed a high-velocity anomaly in the lower crust that may be related to ancient mantle plume activity.

On apparent pronominal feature contradictions: Shifty agreement in Telugu

AbstractThis article investigates so‐called monstrous agreement—where a non‐first‐person pronoun can control first‐person agreement on an embedded verb—in Telugu. Empirically, I provide the most in‐depth description of monstrous agreement in Telugu to date. To account for monstrous agreement, I propose that embedded pronouns have morphosyntactic features that indicate their roles in both the matrix and embedded speech acts. This means an embedded pronoun can have first‐person and third‐ or second‐person features simultaneously. I then propose a precise set of morphosyntactic operations that allow the first‐person feature to appear on the verbal agreement but not the pronoun controlling the agreement. I also show that pronouns that have these contradictory features must be bound by an operator to be licensed, and I discuss the nature of these operators and the locality conditions on the binding relationship. The theoretical consequence of this article is that apparently contradictory feature combinations on pronominal elements must be sanctioned by UG.

Effect of aspect ratio on the wake transition behind a thin pitching plate

We study the influence of Aspect Ratio (AR) on three-dimensional wake transition past a thin pitching plate at Reynolds number of 1000 by performing computations for the range 0.54≤AR≤16 at pitching frequencies St=0.5,1 and maximum pitching angles θmax=5°,15°. For all AR, larger θmax and St promote thrust generation. However, higher AR imparts a stabilizing influence in the wake of the drag regime. For the ranges of AR, the drag-producing wake consisting of horseshoe vortices and bridgelets-type vortex structures, whereas twin-jet type bifurcated wakes with entangled vortices are observed for thrust-generating wakes. At higher AR, the wakes show a two-dimensional signature in the drag regime, whereas a spatial wake transition is observed in the thurst regime. The spanwise wake width shows the effect of wake compression for larger St even at θmax=5°, which is also substantiated by particle tracking showing wake compression for the thrust cases up to AR≤12. The near wake oscillations are prevalent for higher AR, although the core region remains unaffected by the aiding influence of spanwise instability for larger AR. The time average streamwise velocity for both drag and thrust regimes resembles an apparent feature of the reverse von Kármán vortex street.

Environmental Activism and the Fairness of Costs Argument for Uncivil Disobedience

AbstractSocial movements often impose nontrivial costs on others against their wills. Civil disobedience is no exception. How can social movements in general, and civil disobedience in particular, be justifiable despite this apparent wrong-making feature? We examine an intuitively plausible account—it is fair that everyone should bear the burdens of tackling injustice. We extend this fairness-based argument for civil disobedience to defend some acts of uncivil disobedience. Focusing on uncivil environmental activism—such as ecotage (sabotage with the aim of protecting the environment)—we argue that some acts of uncivil disobedience can be morally superior to their civil counterparts, when and because such acts target people who are responsible for environmental threats. Indeed, insofar as some acts of uncivil disobedience can more accurately target responsible people, they can better satisfy the demands of fairness compared to their civil counterparts. In some circumstances, our argument may require activists to engage in uncivil disobedienceeven whencivil disobedience is available.

Research on the spatial differences and influencing factors of integrated urban-rural development in the Yangtze River Delta

Once the integrated urban-rural development enters a high-quality development stage, multiple dimensions would be reflected in population, space, economics, society, and environment, which will further advance sustainable development. An integrated urban and rural development have shown different features, rules, and models amid different social systems and in different development stages. Therefore, it's urgent to scientifically measure the integration level of rural and urban areas, revealing the spatial differences, characteristics, and internal mechanism. Targeting the 41 cities within the Yangtze River Delta, this paper evaluates the integrated urban-rural development in this area based on the global principal component analysis, explores its spatial agglomeration and evolution pattern by ESDA method, analyzes the principal factors that result in the spatial differences in integrated urban and rural development in the Yangtze River Delta and their interactive relations by the geographical detector, and discusses the regional differences between those influencing factors by the geographical weighted regression method. The results indicate that (1) the integrated development of the 41 cities is not balanced and there is a great difference between different cities. (2) The integrated development of this area has shown the apparent feature of geographical agglomeration, or in other words, the central cities have become the forces that drive the development of neighboring cities. (3) Since integrated urban-rural development is influenced by economic development, basic infrastructure, government support, and industrial structure, all regions should put forward suggestions for the formulation of policies accordingly based on realities.

A novel theory of life and its implications on viruses and robots

A novel theory of life is proposed and its implications on the viruses and the future robots are discussed. The universal laws of physics are inferred phenomena that originate from the observed regularity in the physical realm. An apparent distinct feature of living beings compared to the nonliving ones is the presence of a higher level of regularity, which is indicative of a supplemental set of governing laws within the sphere of life. In this article a living or animate being is defined concisely as a natural entity whose internal changes and external behavior cannot be predicted by the universal laws and forces of physics alone at all times. Everything else is nonliving or inanimate. Likewise, life is defined as a supplemental set of laws and influences that act over a confined space which constitutes the domain of life, superimposed on the universal laws and forces of physics. Also, life is shown to be a field phenomenon like a quantum field, except that life pervades a bounded region rather than the entire spacetime. It is argued that life is an agency with causal power rather than an ordinary emergent property, and that a virus qualifies as a living being. The proposed field theory of life predicts that the future robots are unlikely to acquire life, and that the notion of highly intelligent future robots posing an existential threat to humanity is, in all likelihood, an illusion.

Dimensional X-Ray computed tomography: Apparent feature form error and its effect on measurement tasks

X-ray computed tomography (XCT) provides a unique set of dimensional measurement capabilities suitable for assessing complex geometry. However, due to the origins of XCT as a medical imaging method and qualitative non-destructive examination technique, only recently has XCT been rigorously investigated as a dimensional metrology tool. Although the data produced via XCT may be leveraged with conventional coordinate metrology techniques, the instrument physics and volumetric reconstruction methods which govern the accuracy and precision of the data are complex, workpiece-specific, and non-negligible. In particular, there is minimal prior work which has studied complex multi-step metrology tasks such as datum reference frame (DRF) construction and feature position measurement. In this work, a qualified artifact was used to evaluate the fitness of XCT for such a task. Multiple XCT systems were used, and multiple instrument magnification levels compared. The form error of planar and cylindrical features was evaluated. Further, the influence of individual feature reconstruction on the development of datums and upstream position measurements was studied. It was found that negative, i.e., bore-like, and positive, i.e., pin-like configurations of certain features were subject to distinct XCT artifact effects which caused upstream measurement errors when these features were used to construct a DRF. High magnification and X-ray scatter produced high spatial frequency noise in surface reconstruction while beam hardening and beam penetration distance variation produced gross apparent form error. The latter was associated with greater measurement errors in feature position measurement within an DRF.

A Multi-Pedestrian Tracking Algorithm for Dense Scenes Based on an Attention Mechanism and Dual Data Association

Aiming at the problems of frequent identity switches (IDs) and trajectory interruption of multi-pedestrian tracking algorithms in dense scenes, this paper proposes a multi-pedestrian tracking algorithm based on an attention mechanism and dual data association. First, the FairMOT algorithm is used as a baseline to introduce the feature pyramid network in the CenterNet detection network and up-sampling the output multi-scale fused feature maps, effectively reducing the rate of missed detection of small-sized and obscured pedestrians. The improved channel attention mechanism module is embedded in the CenterNet’s backbone network to improve detection accuracy. Then, a re-identification (ReID) branch is embedded in the head of the detection network, and the two sub-tasks of pedestrian detection and pedestrian apparent feature extraction are combined in a multi-task joint learning approach to output the pedestrian apparent feature vectors while detecting pedestrians, which improves the computational efficiency and localization accuracy of the algorithm. Finally, we propose a dual data association tracking model that tracks by associating almost every detection box instead of only the high-scoring ones. For low-scoring detection boxes, we utilize their similarities with trajectories to recover obscured pedestrians. The experiment using the MOT17 dataset shows that the tracking accuracy is improved by 0.6% compared with the baseline FairMOT algorithm, and the number of switches decreases from 3303 to 2056, which indicates that the proposed algorithm can effectively reduce the number of trajectory interruptions and identity switching.

The structure at the centre of the giant radio galaxy GRS J0844+4627: a compact symmetric object?

ABSTRACT We observed the core region of the giant radio galaxy GRS J0844+4627 with e-MERLIN at 1.52 and 5.07 GHz. These observations revealed that the apparent single feature at the centre of GRS J0844+4627, as seen by GMRT, consists of two components separated by 2.7 kpc in projection. Follow-up observations at 1.66 GHz using the EVN unveiled the complex morphologies of the two components. In particular, the south-western component identified with the SDSS J084408.85+462744.2 galaxy morphologically resembles a compact symmetric object (CSO) with a projected linear size of 115 pc. If the CSO hypothesis turns out to be correct, then the overall radio structure of GRS J0844+4627 is triple–double. Given that CSOs are considered young objects, GRS J0844+4627 would appear as a recently restarted active galaxy.

Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae.

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

Action-based personalized dynamic thermal demand prediction with video cameras

Real-time and accurate prediction of indoor thermal demands is of great significance for improving building energy control and human satisfaction. This study proposes a system for dynamically predicting personal thermal demand with ordinary cameras, which integrates action acquisition, action feature extraction, action classification and thermal demand prediction. Three deep learning models were developed and integrated with multiobject tracking algorithms to build a personal thermal demand model. The proposed system and models were validated through a field measurement. The results show that the defined thermal adaptive behaviors can characterize human thermal sensation well. The action feature extraction model constructed based on the apparent feature extraction network combined with the proposed action classification model can determine whether the occupants have taken a thermal adaptive behavior with 92% accuracy and classify the behavior into specific categories with 86% accuracy. The thermal demand prediction model can achieve 95% accuracy, and the overall accuracy of the personal thermal demand model is 91%. This study provides technical and theoretical support for designing intelligent building decision-making schemes based on noninvasive thermal demand prediction.

Impacts of industrial structure adjustment, upgrade and coordination on energy efficiency: Empirical research based on the extended STIRPAT model

This paper first estimates the energy efficiency of 13 cities and 30 key industries in the Beijing-Tianjin-Hebei (BTH) region between 2008 and 2017 using the super-efficiency slacks-based measure (SBM) model. Structural deviation, Moore index, and coupling coordination degree quantify the cities' industrial restructuring, upgrading, and coordination. Afterward, the extended STIRPAT model reveals the relationship between energy efficiency and industrial structure. Finally, a coupling coordination degree model measures the coupling between energy efficiency and industrial advanced development coefficients in key industries. The results show a wide variation in energy efficiency between cities, with most cities experiencing a decline in energy efficiency. Industrial structure adjustment and upgrading are on the rise, and coordination is on the wane, with the most significant changes occurring in the cities around Beijing. In most cities, industrial structure adjustment, upgrading, and coordination on energy efficiency are negative, positive, and negative. The coupling imbalance of energy efficiency and industrial advanced development coefficients is the most apparent feature of the key sectors, and this feature is not improving.

Research on Pedestrian Detection and DeepSort Tracking in Front of Intelligent Vehicle Based on Deep Learning

In order to improve the tracking failure caused by small-target pedestrians and partially blocked pedestrians in dense crowds in complex environments, a pedestrian target detection and tracking method for an intelligent vehicle was proposed based on deep learning. On the basis of the YOLO detection model, the channel attention module and spatial attention module were introduced and were joined to the back of the backbone network Darknet-53 in order to achieve weight amplification of important feature information in channel and space dimensions and improve the representation ability of the model for important feature information. Based on the improved YOLO network, the flow of the DeepSort pedestrian tracking method was designed and the Kalman filter algorithm was used to estimate the pedestrian motion state. The Mahalanobis distance and apparent feature were used to calculate the similarity between the detection frame and the predicted pedestrian trajectory; the Hungarian algorithm was used to achieve the optimal matching of pedestrian targets. Finally, the improved YOLO pedestrian detection model and the DeepSort pedestrian tracking method were verified in the same experimental environment. The verification results showed that the improved model can improve the detection accuracy of small-target pedestrians, effectively deal with the problem of target occlusion, reduce the rate of missed detection and false detection of pedestrian targets, and improve the tracking failure caused by occlusion.

In vivo environmental metabolomic profiling via a novel microextraction fiber unravels sublethal effects of environmental norfloxacin in gut bacteria

Emerging contaminants (ECs), especially antibiotics, have significantly polluted the environment and threaten the living circumstance of organisms. Environmental metabolomic has emerged to investigate the sublethal effects of ECs. However, lacking noninvasive and real-time sample pretreatment techniques restricts its development in environmental toxicology. Hence, in this study, a real-time and in vivo untargeted analytical technique towards microbial endogenous metabolites was developed via a novel composite solid-phase microextraction (SPME) fiber of ZIF-67 and polystyrene to realize the high-coverage capture of living gut microbial metabolites. To reveal the exposure risks of typical antibiotic − norfloxacin (NFX) to gut bacteria, four representative bacteria were exposed to NFX at environmentally relevant levels. Using the proposed SPME fiber, 70 metabolites were identified to obtain an apparent metabolic separation feature between control and NFX-treated (10 ng/mL) microbial groups, which revealed that the low environmental relevant concentration of NFX would affect normal metabolism of gut bacteria. Additionally, NFX exhibited species-specific toxic effects on microbial growth, especially Escherichia coli displaying a distinct dose-dependent trend. Antioxidative enzymatic activities results demonstrated that beneficial bacteria maintained the state of oxidative stress while symbiotic bacteria suffered from oxidative stress injury under NFX contamination, further corroborating its impact on human intestinal health. This study highlights the suitability of in vivo SPME in the field of metabolite extraction and simultaneously possesses a brilliant application foreground in the environmental metabolomics.

Influence of dry-wet cycles on the strength behavior of basalt-fiber reinforced loess

Dry-wet cycle induced loess spalling and collapse frequently occurs in the Loess Plateau, which is an influential trigger for the instability of infrastructure. In order to evaluate the resistance of basalt-fiber reinforced loess to dry-wet action, a digital-image system was used in triaxial shear tests with failure mode and shear strength discussed. The apparent feature and microstructure of fiber-reinforced loess were analyzed using the Particles (Pores) and Cracks Analysis System (PCAS) and Scanning Electron Microscope (SEM). Results show that the shear strength of fiber-reinforced loess gradually decreases with dry-wet cycles, with maximum decline after initial two cycles, while it increases and then decreases at higher fiber contents, with pronounced resistance observed at a fiber content of 0.6%. The loess before reinforcement exhibits brittle failure mode while the plasticity becomes more obvious as the fiber content increases, i.e., overall bulging damage but returns to brittle failure after 5 cycles. The crack ratio, as revealed by PCAS, varies consistently with the strength decay after dry-wet cycles. SEM images indicate that microcracks appear in the loess after dry-wet action and the fiber network enhances the resistance to dry-wet cycles, with the deterioration occurring mainly at the soil-fiber interface. Based on the continuum damage theory, a statistical damage model was proposed for fiber-reinforced loess considering dry-wet and loading damage. Error analysis results show that the model well describes the stress-strain behavior of reinforced loess with different fiber contents after dry-wet cycles.

One-step construction of regular cascade nanostructure and its near-field properties

Uniform and simple construction of metal plasmon nanostructures has become popular for many applications. Thermal evaporative deposition technology has attracted widespread attention in recent years due to its excellent controllability and technical universality. In the current study, large area of uniform Ag cascade nanoparticle arrays (Ag-CNPAs) with multi-scale coupling effect were obtained by one-step method using the confined evaporation deposition technique. Finite-difference time-domain (FDTD) simulation findings demonstrated that Ag-CNPAs have apparent cascade enhancement feature of gradual energy coupling and convergence. Using prepared Ag-CNPAs as surface-enhanced Raman spectroscopy (SERS) active substrates, relative standard deviation (RSD) value of Raman intensity at 1160 cm−1 mode of crystal violet (CV) molecules (with concentration of 10-4 M) was 2.6 %, which indicated homogeneity and excellent near-field enhancement performance of Ag-CNPAs nanostructures. Furthermore, the current study established that SERS substrates were very promising devices. In addition, the current study developed a localized deposition technology that is simple to operate and cheap, which is valuable in large-scale uniform preparation of complex micro-nano structures.