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Solution Existence and Compactness Analysis for Nonsmooth Optimization Problems
Get PDFThis paper is concerned with the analysis of geometrical properties and behaviors of the optimal value and global optimal solutions for a class of nonsmooth optimization problems. We provide conditions under which the solution set of a nonsmooth and nonconvex optimization problem is non-empty and/or compact. We also examine related properties such as the compactness of the sublevel sets, the boundedness from below and the coercivity of the objective function to characterize the non-emptiness and the compactness of the solution set of the underlying optimization problem under the unboundedness of its associated feasible set.This research is funded by Vietnam National University Ho Chi Minh City (VNU-HCM) under grant number T2025-18-01
A Comparative Study of YOLO Series (v3–v10) with DeepSORT and StrongSORT: A Real-Time Tracking Performance Study
Get PDFData Availability Statement: The data presented in this study are openly available in https://motchallenge.net, and reference [14] Everingham, M.; Van Gool, L.; Williams, C.K.; Winn, J.; Zisserman, A. The pascal visual object classes (voc) challenge. Int. J. Comput. Vis. 2010, 88, 303–338. doi url: https://doi.org/10.1007/s11263-009-0275-4..Many previous studies have explored the integration of a specific You Only Look Once (YOLO) model with real-time trackers like Deep Simple Online and Realtime Tracker (DeepSORT) and Strong Simple Online and Realtime Tracker (StrongSORT). However, few have conducted a comprehensive and in-depth analysis of integrating the family of YOLO models with these real-time trackers to study the performance of the resulting pipeline and draw critical conclusions. This work aims to fill this gap, with the primary objective of investigating the effectiveness of integrating the YOLO series, in light-sized versions, with the real-time DeepSORT and StrongSORT tracking algorithms for real-time object tracking in a computationally limited environment. This work will systematically compare various lightweight YOLO versions, from YOLO version 3 (YOLOv3) to YOLO version 10 (YOLOv10), combined with both tracking algorithms. It will evaluate their performance using detailed metrics across diverse and challenging real-world datasets: the Multiple Object Tracking 2017 (MOT17) and Multiple Object Tracking 2020 (MOT20) datasets. The goal of this work is to assess the robustness and accuracy of these light models in multiple complex real-world environments in scenarios with limited computational resources. Our findings reveal that YOLO version 5 (YOLOv5), when combined with either tracker (DeepSORT or StrongSORT), offers not only a solid baseline in terms of the model’s size (enabling real-time performance on edge devices) but also competitive overall performance (in terms of Multiple Object Tracking Accuracy (MOTA) and Multiple Object Tracking Precision (MOTP)). The results suggest a strong correlation between the choice regarding the YOLO version and the tracker’s overall performance.Ahmet Serhat Yildiz’s Ph.D. is sponsored by the Ministry of National Education of Türkiye
Marriage types
Get PDFIf we take a cross-cultural view of human societies, there are few institutions or systems which can be argued to be ‘universal’. Marriage may be the exception. It is found in virtually all societies, and likely has a deep evolutionary history (Shenk, 2024). However, this universality only holds if we define marriage extremely loosely, as the socially recognised union between two or more individuals (Fortunato, 2015). Beyond this, we see significant variation. Given that a key function of marriage is the legalisation and regulation of sex and reproduction, it is easy to see marriage as the cultural analogy of mating systems (chapter 20). Certainly, marriage type often is used as a proxy for mating success. But sex and reproduction occurs outside of marriage and marriage is about much more than just reproduction. It is interwoven with concepts of family and kinship: influencing and being influenced by kin obligations, how descent and inheritance is traced and economic and subsistence systems (Shenk, 2024). We need to understand a lot more about human kinship, inheritance and cultural systems to understand marriage from an evolutionary perspective. In this chapter, we will focus on evolutionary perspective to marriage types in terms of spousal number, reflecting on the diverse forms regularised human partnerships take
Fracturing evolution of red sandstone: insights from three-point bending experiment and numerical simulation considering material inhomogeneity and internal discontinuities
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The data underpinning this publication can be accessed from Brunel University of London's data repository (Brunelfigshare) here under a CCBY license (with the DOI of https://doi.org/10.17633/rd.brunel.28540166).To reveal the various propagation paths of micro-cracks under the continuous process of stress buildup, stress shadow, and stress transfer, three-point bending experiments and numerical simulations were carried out by considering material inhomogeneity and internal discontinuities. The characteristics of red sandstone fracturing evolution were analyzed from the aspects of acoustic emission (AE) energy index, infrared radiation (IR) changes, fracture surface roughness, stress fields and so on. The test results indicate that four stages are divided in the gradual process of energy release of red sandstone fracturing under three-point bending test, the rough fracture surfaces of crack were extremely small, tensile crack makes the largest proportion. IR and AE perform some significant precursor information of rock fracturing, e.g., a large amount of high-temperature debris scattered in infrared thermography, the maximum value of AE accumulative energy and the concentration effect of AE events location. Different tensile stress level has different features, macroscopic fracture morphology happens in a low level, and micro-cracks appears in the weakness of crystal surfaces in a high level. It needs to be emphasized that five different modes, pass through, crack-tip blunting, extended-back, crack-forking and passing round, were concluded in terms of the repeated process of stress buildup, stress shadow & stress transfer. These achievements contribute to the better understanding of the failure mechanisms of red sandstone.The authors thank the financial support from the Jiangxi Provincial Natural Science Foundation, China (Grant No. 20232ACB214007), the National Natural Science Foundation of China, China (Grant No. 41977219) and the UK Research and Innovation (UKRI), UK (Grant No. EP/Y02754X/1), for which the authors are very grateful
Investing in returnee migrants’ health
Get PDFA portion of remittances should be set aside for their healthcare and well-being
Contingency learning of social cues: neural engagement and emotional modulation by facial expressions
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The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found below: 10.6084/m9.figshare.27651537.Contingency learning—the fundamental process by which associations are formed between events in our experience is as relevant of conditioning as it is for social interactions, where emotional cues, such as facial expressions, signal complex and reciprocal causal dynamics. This study investigates the functional neuroanatomy underlying contingency perception by with three type of contingent relation (positive, zero, and negative) using sad and happy facial expressions as stimuli in a group of neurotypical participants. Employing a streaming trial paradigm and functional MRI, we examined how these emotional contingencies engage brain regions involved in attention and predictive processing. The behavioural results indicated that participants could distinguish between different contingencies, regardless of the emotional stimuli. However, judgment ratings varied across conditions, with sad expressions eliciting weaker ratings compared to happy expressions, which moderated perceived causality, especially in the uncorrelated and negative contingency tasks. These behavioural findings were primarily linked to increased activation in frontal regions, including the inferior frontal gyrus, middle frontal gyrus, and anterior cingulate cortex. The results highlight the differential cognitive demands and neural responses evoked by emotional expressions and suggestive of the idea that statistical relations that violate social expectations are processed differently than positive relations.This work was supported by the Scientific and Technological Research Council of Türkiye [Grant Number: 1059B192202594] to Rahmi Saylik. Also, this work was supported by the Ibn Haldun University to cover the article publishing charges [Grant Number: BAP2301] to Burcu Uysal
The Random RFPA Method for Modelling Rock Failure
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The data underpinning this publication can be accessed from Brunel University of London’s data repository, Brunelfigshare here under a CCBY license: https://doi.org/10.17633/rd.brunel.26317462The random rock failure process analysis (RRFPA) method was developed in this research to characterize the material spatial variability and uncertainty in rock failure modelling. The random field theory (RFT) was integrated with the traditional rock failure process analysis (RFPA) to model rock heterogeneity. In this approach, the variation of rock properties is represented as a function of relative distance, such that the influence of material intrinsic correlation on its fracturing behaviour can be appropriately captured. To validate the theory, 300 RRFPA simulations were conducted to investigate the failure characteristics of rock samples under compressive loading. The results showed that by incorporating a spectrum of material properties, the numerical outcomes exhibited distinct upper and lower bounds of stress across all testing scenarios, closely aligning with the experimental relationships. The histograms for uniaxial compressive strength and elastic modulus showed that both properties followed normal distributions, with the average values of 10.099 MPa and 1.818 GPa, respectively. The corresponding coefficients of variation were 0.450 and 0.038. The localized failure tended to result in a more rapid release of acoustic emission energy, but generated smaller cumulative energy compared to the overall failure pattern. In general, the maximum relative error of the RRFPA model was only 0.66% for uniaxial compressive strength, elastic modulus, and critical axial strain.This work was supported by UK Research and Innovation, EP/Y02754X/1, Bin Gong; UK Engineering and Physical Sciences Research Council, EP/V028723/1, Tao Zhao; Royal Society, IES\R2\242319, Bin Gong
Contested geographies of trafficking borders
Get PDFThis article introduces a special issue on Contested Geographies of Trafficking Borders. This collection broadens the understanding of trafficking borders by examining their materialisation, impacts, and contestation across different spaces and times. Expanding this notion of Trafficking Borders, the articles in this issue explore key questions: Where are trafficking borders found, and how do they manifest? Who creates these borders, and what are their motivations? How do those targeted by trafficking discourse resist them? How can researchers effectively study trafficking borders? Together, these contributions establish a critical agenda for contesting the geographies of trafficking borders.The author(s) received no financial support for the research, authorship, and/or publication of this article
Encryption-decryption-based set-membership filtering for two-dimensional systems: on security and boundedness
Get PDFIn this paper, the encryption-decryption-based set-membership filtering issue is considered for a class of networked two-dimensional systems with unknown-but-bounded noises. In order to preserve data privacy and reduce communication burden, an encryption-decryption mechanism is put forward based on the exclusive or logical operation technique and the one-time pad method, under which the data is encrypted into a ciphertext with finite bits before being transmitted through the networks. The aim of the addressed problem is to develop an encryption-decryption-based set-membership filter (EDSMF) that is capable of generating an ellipsoidal set that contains the true system state and ensuring the security performance. Sufficient conditions are established for the existence of the desired ellipsoidal set, and the corresponding EDSMF gains are obtained by applying the Lagrange multiplier method. Moreover, the uniform boundedness of the ellipsoidal shape-defining matrix is thoroughly studied. Finally, the effectiveness of the proposed filter design method is demonstrated by a practical example of a heat exchanger.National Natural Science Foundation of China under Grants 61933007, 62403318, and U21A2019; in part by the Shanghai Pujiang Program of China under Grant 22PJ1411700; in part by the China Postdoctoral Science Foundation under Grant 2023M732322; in part by the Royal Society of the UK; and in part by the Alexander von Humboldt Foundation of Germany
Self-Perceptions of Ageing Predict Recovery After a Fall: Prospective Analysis from the English Longitudinal Study of Ageing
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Key points:
• This study provides the first evidence that older individuals who had more positive self-perceptions of aging at baseline were better protected against negative physical consequences following a subsequent fall.
• These results remained statistically significant after adjusting for important covariates including baseline gait speed, ADL dependence and physical inactivity, identifying self-perceptions of aging as an important independent predictor of physical recovery following a fall.
• These novel findings highlight the potential of psycho-social factors to influence physical recovery from a fall in older adults.
Why does this paper matter?
• The present findings identify self-perceptions of aging as a robust predictor of physical function and disability following a fall, independent of other important factors such as age, gender, and pre-fall physical function.
• These novel observations advance our understanding of the psychological factors impacting physical recovery from a fall and suggest that assessment of self-perceptions of aging could help identify older adults requiring additional support following a fall.
• This could lead to enhanced recovery outcomes for older adults, ultimately reducing the burden of disability and improving quality of life after falls.Acknowledgments:
The English Longitudinal Study of Aging was developed by a team of researchers based at University College London, NatCen Social Research, the Institute for Fiscal Studies, and the University of Manchester. The data were collected by NatCen Social Research. The authors would like to thank participants of the ELSA study.Objective:
To investigate how mindsets around aging at baseline affect physical recovery following a subsequent fall.
Design:
Longitudinal observational study.
Setting:
English Longitudinal Study of Aging (ELSA).
Participants:
We analyzed data for 694 individuals who had not fallen in the 2 years prior to baseline (Wave 4) but experienced a fall during follow-up (between Waves 4 and 5).
Measurements:
Self-perceptions of aging at baseline (Wave 4) and gait speed, activities of daily living (ADL) dependence, and physical (in)activity after a fall at a 2-year follow-up (Wave 5). Multivariable logistic regression analyses were used to determine to what extent aging-related mindset variables as measured at baseline predicted outcome measures at follow-up.
Results:
In a fully-adjusted model controlling for confounding baseline factors (including baseline gait speed, ADL dependence and physical inactivity), individuals with positive self-perceptions of aging at baseline had significantly lower odds of slow gait speed (OR = 0.729; 95% CI = 0.627–0.849), ADL dependence (OR = 0.667; 95% CI = 0.561–0.792) and physical inactivity (OR = 0.795; 95% CI = 0.700–0.904) following a fall at a 2-year follow-up.
Conclusions:
These findings identify self-perceptions of aging as a strong predictor of physical recovery and disability following a fall, independent of other important factors such as age, gender, and pre-fall physical function. These novel observations advance our understanding of the psychological factors impacting physical recovery from a fall. Future work should explore if targeting such perceptions can directly improve physical recovery and outcomes following a fall.English Longitudinal Study of Aging (ELSA) funding is provided by the National Institute of Aging in the USA, and a consortium of UK government departments coordinated by the Economic and Social Research Council. This work was partially supported by a Wellcome Trust Sir Henry Wellcome Postdoctoral Fellowship awarded to Toby J. Ellmers (Grant Number: 222747/Z/21/Z)
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