Miracle-dz/UniFAR-FTUs huggingface dataset:
Scalable Operator Allocation for Multirobot Assistance: A Restless Bandit Approach

In this article, we consider the problem of allocating human operators in a system with multiple semiautonomous robots. Each robot is required to perform an independent sequence of tasks, subject to a chance of failing and getting stuck in a fault state at every task. If and when required, a human operator can assist or teleoperate a robot. Conventional dynamic programming-based techniques used to solve such problems face scalability issues due to an exponential growth of state and action spaces with the number of robots and operators. In this article, we derive conditions under which the operator allocation problem satisfies a technical condition called indexability, thereby enabling the use of the Whittle index heuristic. The conditions are easy to check, and we show that they hold for a wide range of problems of interest. Our key insight is to leverage the structure of the value function of individual robots, resulting in conditions that can be verified separately for each state of each robot. We apply these conditions to two types of transitions commonly seen in remote robot supervision systems. Through numerical simulations, we demonstrate the efficacy of Whittle index policy as a near-optimal and scalable approach that outperforms existing scalable methods.
A Comprehensive Study of Clustering a Class of 2D Shapes

Abstract The paper is concerned with clustering with respect to the shape and size of 2D contours that are boundaries of cross-sections of 3D objects of revolution. We propose a number of similarity measures based on combined disparate Procrustes analysis (PA) and dynamic time warping (DTW) distances. A motivation and the main application for this study comes from archaeology. The computational experiments performed refer to the clustering of archaeological pottery.
Sensing characteristics of long period gratings in hollow core fiber fabricated via electrode arc discharge

This paper reports on the fabrication of Long Period Gratings (LPGs) in hollow-core air-silica photonic bandgap fibers (HC-PCFs) by using pressure assisted Electrode Arc Discharge (EAD) technique. In particular, the fabrication procedure relies on the combined use of EAD step, to locally heat the HC fiber, and of a static pressure (slightly higher than the external one) inside the fiber holes, to modify the holes. Here, the experimental fabrication of LPG prototypes with different periods and lengths are discussed. And, the sensitivity of LPGs in HC-PCF to environmental parameters such as strain, temperature and static pressure are presented and discussed.
Deep Reinforcement Model Selection for Communications Resource Allocation in On-Site Medical Care

Greater capabilities of mobile communications technology enable the interconnection of on-site medical care at a scale previously unavailable. However, embedding such critical, demanding tasks into the already complex infrastructure of mobile communications has proven challenging. This paper explores a resource allocation scenario where a scheduler must balance mixed performance metrics among connected users. To fulfill this resource allocation task, we present a scheduler that adaptively switches between different model-based scheduling algorithms. We make use of a deep Q-Network (DQN) to learn the benefit of selecting a scheduling paradigm for a given situation, combining advantages from model-driven and data-driven approaches. The resulting ensemble scheduler is able to combine its constituent algorithms to maximize a sum-utility cost function while ensuring performance on designated high-priority users.
Higher-Order Coverage Errors of Batching Methods via Edgeworth Expansions on $t$-Statistics

While batching methods have been widely used in simulation and statistics, it is open regarding their higher-order coverage behaviors and whether one variant is better than the others in this regard. We develop techniques to obtain higher-order coverage errors for batching methods by building Edgeworth-type expansions on t-statistics. The coefficients in these expansions are intricate analytically, but we provide algorithms to estimate the coefficients of the n−1 error term via Monte Carlo simulation. We provide insights on the effect of the number of batches on the coverage error where we demonstrate generally non-monotonic relations. We also compare different batching methods both theoretically and numerically, and argue that none of the methods is uniformly better than the others in terms of coverage. However, when the number of batches is large, sectioned jackknife has the best coverage among all. Keywords— Batching methods, Edgeworth expansion, coverage errors, simulation analysis
Monitoring the Vibrations of Variable and Varying Speed Gearboxes

This paper proposes an approach to monitor the condition of variable and varying speed gearboxes. The approach consists of estimating frequency response functions (FRFs) of a gearbox based on classical vibration parameters. These classical vibration parameters include both time domain parameters (kurtosis number, RMS value, peak-to-peak value and crest factor) and frequency domain parameters (peak values of the gear mesh frequency and its harmonic components and the matched-filter RMS value). Trending of the FRFs based on these classical vibration parameters is expected to reflect changes in the operating conditions of variable or varying speed gearboxes. The estimated FRF can also be used to normalise all measurements taken at different speeds to one reference speed. Discussions on using the Short-Time Fourier Transform (STFT) approach and Order Tracking Analysis to estimate the new vibration parameter are also provided. A digital simulation based on the STFT approach was carried out to further clarify the concept and measuring methodology of the new approach.
ROADMAP 2021 roadmap on lithium sulfur batteries

Batteries that extend performance beyond the intrinsic limits of Li-ion batteries are among the most important developments required to continue the revolution promised by electrochemical devices. Of these next-generation batteries, lithium sulfur (Li–S) chemistry is among the most commercially mature, with cells offering a substantial increase in gravimetric energy density, reduced costs and improved safety prospects. However, there remain outstanding issues to advance the commercial prospects of the technology and benefit from the economies of scale felt by Li-ion cells, including improving both the rate performance and longevity of cells. To address these challenges, the Faraday Institution, the UK’s independent institute for electrochemical energy storage science and technology, launched the Lithium Sulfur Technology Accelerator (LiSTAR) programme in October 2019. This Roadmap, authored by researchers and partners of the LiSTAR programme, is intended to highlight the outstanding issues that must be addressed and provide an insight into the pathways towards solving them adopted by the LiSTAR consortium. In compiling this Roadmap we hope to aid the development of the wider Li–S research community, providing a guide for academia, industry, government and funding agencies in this important and rapidly developing research space. © 2021 The Author(s). Published by IOP Publishing Ltd J. Phys. Energy 3 (2021) 031501 J B Robinson et al
Guest Editorial Special Issue on Wireless Sensor and Actuator Networks

The 16 full papers and 7 technical notes in this special issue focus on wireless sensor and actuator networks. The full papers in this issue can be broadly organized into three main categories: (i) control with WSANS, (ii) control of WSANS, and (iii) WSAN node placement/deployment.
Analysis of Rectangular Planar Array with Different Distributions and Optimization of Sidelobe Level using GA and PSO

In this paper, analysis of rectangular planar antenna array(RPAA) with different amplitude distributions like uniform, binomial and Dolph-Tschebyshev distributions is done. Comparison of radiation characteristics of rectangular planar arrays with different amplitude distributions is done. The sidelobe level (SLL) is optimized using genetic algorithm (GA) based optimization and particle swarm optimization (PSO) techniques. Keywords— Rectangular planar antenna array (RPAA), Sidelobe level (SLL), Half power beam width (HPBW), Genetic algorithm, Particle swarm optimization.
STUDY ON CHARACTERISTICS OF AERODYNAMIC SOUND RADIATED FROM LONGITUDINAL VORTEX GENERATED AROUND THE LEADING EDGE OF A DELTA

Longitudinal vortex generated behind frontpillar of a vehicle is reproduced by delta wing with attack angle of 15 degrees was merged in the uniform flow at 10, 20, and 30 m/s. Computational Fluid Dynamics (CFD) visualized the longitudinal vortex behind the leading edge of delta wing, and clarified that the vortex had the highest rotational speed at the tip and decreased the speed in the rearward direction. Since time derivative of surface pressure fluctuations is regarded as sound sources, they are correlated with aerodynamic sound measured in the low noise wind tunnel. As a result, it was found that sound sources at the tip of the vortex had strong correlation with aerodynamic sound in higher frequency range whereas those at the rear in the lower frequency range. CFD revealed vorticity distributions in the vortex. The vorticity at the tip is the strongest and becomes weaker and weaker in the rearward direction. It therefore follows that fluid particles with stronger vorticity at the tip induce larger level of pressure fluctuations with higher frequency. This leads to sound generation with large level of high frequency. Meanwhile, the fluid particles with the weaker vorticity at the rear induce the smaller level of pressure fluctuations with lower frequency. This leads to sound generation with small level of low frequency.
Pushing with a physics-based model

Humans often push when grasping or lifting is inconvenient or infeasible, because pushing requires fewer contacts and fights against only a fraction of the object's weight. However, pushing results are hard to predict, because the physical parameters that govern the pushing motion are difficult to measure. We derived a physics-based box pushing model and implemented a feedback-based pushing pipeline using the model. Experimental results show that our pushing model has fair predictive power and our pushing pipeline can reliably push the target to the goal. We compared our physics-based method to a minimalistic baseline pushing method and showed that our method is more accurate and reliable. Thesis Supervisor: Tomas Lozano-Perez Title: Professor
Target mode selection based on load indicators

Three approaches were compared to evaluate their capabilities for selecting the target modes of a structure. The modal effective mass approach was based on the structural stiffness and mass matrices, while the modal load indicator approach included the effects of load path, and the transient load factor took into account both load path and the dynamic characteristics of the excitations. Both modal effective mass and modal load indicator approaches did not require the knowledge of the excitations and could be conducted at the early phase of the design process or during the planning of the modal survey. The transient load indicator approach involved more analysis and is more costly. However, it provided a direct indication of significant modes which would be critical to the structural integrity. Example was given to demonstrate the advantages of each approach. The results showed that the modal effective mass approach was capable of identifying majority of the significant modes on the system level, and the modal or transient load indicators approaches could be used to identify target modes of both system and subsystems, especially for lightweight subsysterns.
A cross-species framework to identify vocal learning abilities in mammals

Vocal production learning (VPL) is the experience-driven ability to produce novel vocal signals through imitation or modification of existing vocalizations. A parallel strand of research investigates acoustic allometry, namely how information about body size is conveyed by acoustic signals. Recently, we proposed that deviation from acoustic allometry principles as a result of sexual selection may have been an intermediate step towards the evolution of vocal learning abilities in mammals. Adopting a more hypothesis-neutral stance, here we perform phylogenetic regressions and other analyses further testing a potential link between VPL and being an allometric outlier. We find that multiple species belonging to VPL clades deviate from allometric scaling but in the opposite direction to that expected from size exaggeration mechanisms. In other words, our correlational approach finds an association between VPL and being an allometric outlier. However, the direction of this association, contra our original hypothesis, may indicate that VPL did not necessarily emerge via sexual selection for size exaggeration: VPL clades show higher vocalization frequencies than expected. In addition, our approach allows us to identify species with potential for VPL abilities: we hypothesize that those outliers from acoustic allometry lying above the regression line may be VPL species. Our results may help better understand the cross-species diversity, variability and aetiology of VPL, which among other things is a key underpinning of speech in our species. This article is part of the theme issue ‘Voice modulation: from origin and mechanism to social impact (Part II)’.
Speech modifications in interactive speech: effects of age, sex and noise type

When attempting to maintain conversations in noisy communicative settings, talkers typically modify their speech to make themselves understood by the listener. In this study, we investigated the impact of background interference type and talker age on speech adaptations, vocal effort and communicative success. We measured speech acoustics (articulation rate, mid-frequency energy, fundamental frequency), vocal effort (correlation between mid-frequency energy and fundamental frequency) and task completion time in 114 participants aged 8–80 years carrying out an interactive problem-solving task in good and noisy listening conditions (quiet, non-speech noise, background speech). We found greater changes in fundamental frequency and mid-frequency energy in non-speech noise than in background speech and similar reductions in articulation rate in both. However, older participants (50+ years) increased vocal effort in both background interference types, whereas younger children (less than 13 years) increased vocal effort only in background speech. The presence of background interference did not lead to longer task completion times. These results suggest that when the background interference involves a higher cognitive load, as in the case of other speech of other talkers, children and older talkers need to exert more vocal effort to ensure successful communication. We discuss these findings within the communication effort framework. This article is part of the theme issue ‘Voice modulation: from origin and mechanism to social impact (Part II)’.
SIMULATION OF CRACKING IN LARGE ARCH DAM: PART I

A complete fracture mechanics investigation of the cracking of the Kolnbrein arch dam is presented in two parts. In Part I, the history of cracking of this dam and theories attempting to explain it are described. The fundamental principles of mixed‐mode, linear elastic fracture mechanics are then elucidated and used to study cracking observed near the toe of the dam. The stability, trajectory, and opening of two cracks are computed and favorably compared to observations. In Part II, cracking which occurred in the heel region of the dam is investigated next using computer simulation and fracture mechanics in an attempt to reproduce observed trajectory and load history before cracking. Four models for the cause of this cracking are described. All four models are shown to be viable mechanisms within the constraints of available cracking data. The necessity for combining simulation with accurate data of various types, and the insufficiency of two‐dimensional analysis are discussed. The significant implication.
The Challenge of Assessing Reflection: The Open University's Access Programme

The Challenge of Assessing Reflection: The Open University’s Access Programme Book Section How to cite: Butcher, John; Sinclair, Stefanie and Clarke, Anactoria (2015). The Challenge of Assessing Reflection: The Open University’s Access Programme. In: Miller, Wendy; Collings, Jane and Kneale, Pauline eds. Inclusive Assessment. PedRIO Papers (7). Plymouth University: Pedagogic Research Institute and Observatory (PedRIO), pp. 25–29.
Modeling traffic crash rates of road segments through a lognormal hurdle framework with flexible scale parameter

Summary This study examines distributional characteristics of crash rates for road segments using observed accident data. The results indicate that the distribution of crash rates is mixed and right-skewed, which motivates the consideration of non-normal distributions. With the aid of Kolmogorov–Smirnov tests, kernel density plots, and Q–Q plots, the lognormal distribution is verified as an appropriate candidate for representing the positive domain of crash rates. Then, a lognormal hurdle model was developed and also compared with gamma and Weibull hurdle models. Further, the lognormal hurdle model was revised by allowing the scale parameter to vary with respect to explanatory variables. Such a modification enables the heterogeneous skewness of samples to be captured while enhancing the modeling flexibility. The proposed model was also compared with a Tobit model, an alternative approach that treats crash rates as censored data. Among all these models, the proposed lognormal hurdle model with flexible scale parameter presents the best modeling performance, and the analyses also reveal that several explanatory variables affect crash rates through not only the location parameter but also the scale parameter in the lognormal model. This study finally attempted to inspect crash rates through count models, and it discovered that the proposed hurdle model is superior because it is able to output the whole distribution form of crash rates, whereas the crash count model can only provide the expected value of crash rates, provided the exposure variable servers as an offset term in the link function of the mean parameter. Copyright © 2015 John Wiley & Sons, Ltd.
Nanopore adaptive sampling for mitogenome sequencing and bloodmeal identification in hematophagous insects

Blood-feeding insects are important vectors for an array of zoonotic pathogens. Despite significant research focused on well-documented insect vectors of One Health importance, resources for molecular species identification of a large number of hematophagous arthropods are limited. Advancements in next-generation sequencing technologies provide opportunities for targeting mitochondrial genomes of blood-feeding insects, as well as their bloodmeal hosts. This dual approach holds great promise for elucidating complex disease transmission pathways and enhancing the molecular resources for the identification of cryptic insect species. To this end, we leveraged the newly developed Oxford Nanopore Adaptive Sampling (NAS) pipeline to dually sequence the mitogenomes of hematophagous insects and their bloodmeals. Using NAS, we sequenced the entire mitogenomes of Aedes vexans, Culex restuans, Culex territans, and Chrysops niger and successfully identified bloodmeal hosts of Chrysops niger, Culex restuans, and Aedes trivittatus. We show that NAS has the utility to simultaneously molecularly identify blood-feeding insects and characterize disease transmission pathways through bloodmeal host identification. Moreover, our data indicate NAS can facilitate a wide array of molecular systematic studies through novel ‘phylogenetic capture’ methods. We conclude the NAS approach has great potential for informing global One Health initiatives centered on the mitigation of vector-borne disease through dual vector and bloodmeal identification.
Interpersonal Relatedness and Non-suicidal Self-Injurious Behaviors in Female Adolescents With Borderline Personality Disorder

Background: Psychopathological models of adolescent borderline personality disorder (BPD) suggest that non-suicidal self-injuring (NSSI)—a particularly frequent symptom in girls—may constitute a way of coping with distress resulting from interpersonal concerns they typically experience as a developmental psychopathological feature. Objectives: Our objective was to investigate the relationship in BPD female adolescents between NSSI and the Sidney Blatt two-polarities model of personality development, which focuses on the psychological processes of interpersonal relatedness and self-definition. Methods: The study was conducted within the European Research Network on Borderline Personality Disorder in Adolescence, using the Depressive Experience Questionnaire (DEQ). Results: BPD patients (n = 59; mean age = 16.6 ± 1.3) scored significantly higher than healthy controls on the two DEQ sub-factors assessing the more immature forms of Interpersonal Relatedness (Neediness) and Self-definition (Self-criticism) and significantly lower on the more mature form of Self-definition (Efficacy). BPD adolescents with NSSI showed significantly higher scores on both mature and immature forms of Interpersonal Relatedness (Neediness and Connectedness) compared to BPD adolescents without NSSI. A logistic regression analysis showed that the subfactor Neediness of the DEQ was the only significant predictor of the presence of NSSI among BPD adolescents. Conclusions: The preliminary results of this study suggests that NSSI in adolescents with BPD is developmentally linked to high developmental concerns in the domain of interpersonal relatedness, which may be taken into consideration in clinical practice. More studies are necessary to better understand the relationships between NSSI and developmental psychopathology in borderline adolescents.
Genitourinary Syndrome of Menopause: Epidemiology, Physiopathology, Clinical Manifestation and Diagnostic

Genitourinary syndrome of menopause (GSM) is a term used to define a compilation of signs and symptoms arising from decreased estrogenic stimulation of the vulvovaginal and lower urinary tract. Among 27–84% of women in postmenopausal are affected for symptoms of GSM, and these can unquestionably impair health, sexual function, consequently the quality of life of these women. The main signs and symptoms of GSM include, among others, burning, irritation, vulvovaginal dryness, dyspareunia, urinary symptoms of urgency, dysuria, or recurrent urinary tract infection. The diagnosis can be made through anamnesis, questionnaires, physical exams, and, sometimes, complementary exams. Objective vaginal assessment is essential and can be complemented by using the Vaginal Health Index (VHI), Vaginal Maturation Index (VMI), or vaginal pH measurement. The acknowledgment of this condition by health professionals is crucial for its identification and proper management and exclusion of other conditions that make a differential diagnosis with it.