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Flag Sequence Set Design for Low-Complexity Delay-Doppler Estimation
Get PDFThis paper studies Flag sequences for lowcomplexity delay-Doppler estimation by exploiting their distinctive peak-curtain ambiguity functions (AFs). Unlike the existing Flag sequence designs that are limited to prime lengths and periodic auto-AFs, we aim to design Flag sequence sets of arbitrary lengths with low (nontrivial) periodic/aperiodic auto- and cross- AFs. Since every Flag sequence consists of a Curtain sequence and a Peak sequence, we first investigate the algebraic design of Curtain sequence sets of arbitrary lengths. Our proposed design gives rise to novel Curtain sequence sets with ideal curtain auto-AFs and zero/near-zero cross-AFs within the delay- Doppler zone of operation. Leveraging these Curtain sequence sets, two optimization problems are formulated to minimize the weighted integrated masked sidelobe level (WImSL) of the Flag sequence set. Accelerated parallel partially majorizationminimization algorithms are proposed to jointly optimize the transmit Flag sequences and symmetric/asymmetric reference sequences stored in the receiver. Simulations demonstrate that our proposed Flag sequences lead to improved WImSL and peak-to-max-masked-sidelobe ratio compared with the existing Flag sequences. Additionally, our Flag sequences under the Flag method exhibit Mean Squared Errors that approach the Cramér- Rao lower bound and the sampling bound at high signal-to-noise power ratios
Motion stability analysis of beaver-like robot
Get PDFA stability index and evaluation method based on couple moment judgment are proposed for the motion stability of beaver-like robot. The index, expressed by the ratio of the recovery torque and external disturbance torque caused by gravity and buoyancy of the beaver-like robot, effectively evaluates the robot’s motion stability. The swimming stability index of beaver-like robot is calculated on the basis of Adams–Matlab co-simulation. Through comparative analysis of the indexes calculated in accordance with experimental and simulation data under different gaits, the stability of the robot in the rolling direction is confirmed to be worse under alternating gaits. The stability in the pitching direction is worse under synchronous gaits. Moreover, the increase of the motion amplitude of the propulsion structure (hind legs and tail) reduces the motion stability of the robot. This research can lay the foundation for stability criteria in underwater stable motion control and motion optimization of beaver-like robots
Robots vs. human employees’ influence on restaurant brand relationship building: An integration of role theory and stereotype theory
Get PDF Despite the popularity of service robot integration in restaurants, it is still unclear whether robots and human employees would influence customer experience, particularly customers’ restaurant brand relationship-building experience, differently. Taking a role theory perspective and building on the stereotypes literature, this study aims to address this research gap. Further, this study tests the moderating roles of stereotypes of warmth and competence toward robots in the proposed relationships. Using two studies, we examined the main effects of restaurant roles on brand relationship building with a scenario of customers at casual dining restaurants in study 1 and we tested the moderating effects with a scenario of customers at robot-themed restaurants at a theme park in study 2. This study contributes novel theoretical insights on robot roles in branding and provides managers with implications for adopting robots. </jats:p
Essays on equity finance and small firms
Get PDFThis thesis comprises three main empirical chapters, an Introduction and Conclusion. Chapter 2 analyses 903 firms that voluntarily delisted from the London Alternative Investment Market (AIM) to identify the factors affecting this delisting. The models are estimated using logit and propensity score matching is used to deal with endogeneity issues. It finds that the likelihood of voluntary delisting is positively related to firm size and growth opportunities, while it is negatively related with intangible assets and profitability levels. Chapter 3 examines firms' preferences for private equity versus public equity by analysing 261 equity crowdfunding offerings on Crowdcube versus 122 AIM offerings in the UK from 2013 to 2018. It concludes that firms with lower pre-money valuations and reduced equity offerings are more inclined towards equity crowdfunding. Moreover, companies with a lower proportion of stock issued and higher pre-money valuations have superior results in ECF campaigns. Chapter 4 analyses the performance of ECF campaigns on the unique angel crowdfunding platform, SyndicateRoom. Utilizing a sample of 130 campaigns on SyndicateRoom from 2013 to 2018, the analysis concludes that companies with more substantial fundraising goals attract more capital, and a higher level of equity offered increases individual investor participation. When comparing with financially comparable campaigns on the other platforms, campaigns on SyndicateRoom demonstrate worse performance regarding the likelihood of meeting fundraising goals and of the total capital raised. The last chapter presents a conclusion, delineates the constraints that observed throughout the research, and proposes prospective avenues for future studies
Combining Real‐Time Neuroimaging With Machine Learning to Study Attention to Familiar Faces During Infancy: A Proof of Principle Study
Get PDFABSTRACTLooking at caregivers’ faces is important for early social development, and there is a concomitant increase in neural correlates of attention to familiar versus novel faces in the first 6 months. However, by 12 months of age brain responses may not differentiate between familiar and unfamiliar faces. Traditional group‐based analyses do not examine whether these ‘null’ findings stem from a true lack of preference within individual infants, or whether groups of infants show individually strong but heterogeneous preferences for familiar versus unfamiliar faces. In a preregistered proof‐of‐principle study, we applied Neuroadaptive Bayesian Optimisation (NBO) to test how individual infants’ neural responses vary across faces differing in familiarity. Sixty‐one 5–12‐month‐olds viewed faces resulting from gradually morphing a familiar (primary caregiver) into an unfamiliar face. Electroencephalography (EEG) data from fronto‐central channels were analysed in real‐time. After the presentation of each face, the Negative central (Nc) event‐related potential (ERP) amplitude was calculated. A Bayesian Optimisation algorithm iteratively selected the next stimulus until it identified the stimulus eliciting the strongest Nc for that infant. Attrition (15%) was lower than in traditional studies (22%). Although there was no group‐level Nc‐difference between familiar versus unfamiliar faces, an optimum was predicted in 85% of the children, indicating individual‐level attentional preferences. Traditional analyses based on infants’ predicted optimum confirmed NBO can identify subgroups based on brain activation. Optima were not related to age and social behaviour. NBO suggests the lack of overall familiar/unfamiliar‐face attentional preference in middle infancy is explained by heterogeneous preferences, rather than a lack of preference within individual infants.</jats:p
SS-ARGNet: A Novel Cascaded Schema for Robots’ 7-DoF Grasping in Adjacent and Stacked Object Scenarios
Get PDFMultiple objects in tightly adjacent and stacked configurations pose significant challenges for robotic systems in achieving reliable grasping, as existing algorithms often struggle to distinguish stacked objects and are prone to causing disruptions to the original scene due to improper grasping postures and collisions. In order to address these challenges, we developed a category-agnostic segmentation and cascaded 7-degrees of freedom (DoF) pose prediction approach for adjacent and stacked objects grasping, using a single vision image. Specifically, a stacked segmentation network (SS-Net) was tailored based on transformer and region proposal modules to achieve robust mask prediction, thereby accurately localizing candidates within the scene. Simultaneously, the attention residual grasping network (ARG-Net) was proposed to estimate the 7-DoF pose of individual targets, employing a new collision-free strategy to avoid interference between the gripper and the candidates. The integrated SS-Net and ARG-Net (SS-ARGNet) schema significantly enhances robotic performance in practical applications, achieving grasp completion rates of 92.8% and 89.1% for adjacent scenarios, and 87.4% and 84.9% for stacked scenarios, for similar and unknown objects, respectively, with a grasp response time of less than 0.9 s
Musculoskeletal First Contact Practitioners Undertaking a Higher Education Training Route-A Qualitative Exploration of Clinical Supervision Experiences.
Get PDFBackground: Musculoskeletal First Contact Practitioners (FCPs) are employed in primary care to assess patients and decrease workload for general practitioners. FCP training requirements are outlined in The Roadmap to Practice (RTP), which includes clinical supervision. Methods: In this qualitative study, 12 musculoskeletal FCPs who had completed FCP training at a specific English university participated in semi-structured interviews that explored their clinical supervision in primary care. Results: Thematic analysis identified three themes: operational factors, the role of personal and professional identity and the dynamics of learning. Participants reported variation in support and organisation provided in their places of work and the impact on their learning; specific barriers related to employment contracts were highlighted. Participants reflected on personal and professional factors that were inconsistently addressed, including cultural competence and the relevance of neurodiversity for both patients and professionals. Positive elements were raised relating to learning dynamics, including accessing supervision from more than one individual and representatives from more than one profession. The bidirectional learning opportunities offered from clinical supervision were highlighted, including supervisors who are not musculoskeletal specialists accessing musculoskeletal expertise from their mentees and the FCPs benefitting from supervisors who have extensive experience of managing complex consultations in primary care. Conclusion: Clinical supervision experiences of FCPs in this study were typically positive. High-quality supervision is dependent on stakeholders fully understanding the role and is optimised by multi-professional involvement. Future studies could include evaluation of referral patterns and clinical outcomes of FCPs from varying employment frameworks
Evaluating musculoskeletal imaging communication interventions using behavioural science: a scoping review using the COM-B model.
Get PDFObjectives Clinicians and patients have been found to attribute musculoskeletal (MSK) pain to normal age-related changes seen on imaging, which can negatively impact patient outcomes and increase healthcare costs. While some studies have tested interventions to improve how MSK imaging findings are communicated, their impact has been limited. Applying a behavioural science framework has the potential to identify the rationale and target of these interventions to inform future intervention design - an analysis that has not yet been conducted. This study aims to identify the Behaviour Change Techniques (BCTs), the behavioural targets and the theoretical basis of interventions seeking to affect the communication of MSK imaging. Design Scoping review using the Capability, Opportunity, Motivation - Behaviour (COM-B) model. Data sources Searches of MEDLINE, EMBASE, CINAHL, AMED and PsycINFO from inception to 9 February 2024. Eligibility criteria for selecting studies We included studies that have developed or evaluated interventions which target the communication of MSK imaging findings. Interventions targeting both patients and clinicians were included. Experimental and quasi-experimental study designs were included, and studies that focused on serious or specific known causes of MSK pain were excluded. Data extraction and synthesis Two independent authors extracted study participant data and intervention details. A theory of behaviour called the COM-B model was used to map the BCTs and behavioural components targeted by studies. Results We identified 11 studies from 2486 studies in our electronic search. 11 different BCTs were identified across 11 studies. The most common techniques were framing/reframing (nine studies), adding objects to the environment (eight studies), incompatible beliefs (seven studies) and avoidance/reducing exposure to cues for the behaviour (four studies). Only two studies (feasibility studies) used behavioural theory to guide their intervention design. While one study showed a large effect, most interventions had little to no impact on pain, disability, or fear over time. Conclusion This review highlighted a lack of studies targeting clinician knowledge and the provision of high-quality patient resources about the nature of MSK pain, even though the broader literature identifies both as enablers of effective health communication. Additionally, the absence of a theory-informed design likely resulted in attempts to reassure patients about normal age-related imaging findings without providing an alternate, more coherent explanation for symptoms. Future interventions should focus on enhancing clinician psychological capability (knowledge) as well as clinician and patient reflective motivation (beliefs) to enable more helpful explanations of MSK symptoms. The key challenge for future interventions will be achieving these aims in a way that is effective, consistent and practical. Trial registration details Open Science Framework (https://doi.org/10.17605/OSF.IO/ECYS8)
Workplace Violence is Home Now for Healthcare Workers: Spillover Theory Perspective
Get PDFn recent years, workplace violence has become an escalating concern, particularly within the healthcare sector. Healthcare workers, who dedicate their lives to caring for others, are increasingly facing violence within their workplaces as evidenced by existing studies. However, literature overlooks complex associations between workplace violence, workplace stress, and domestic violence and stress. This article explores the phenomenon of workplace violence among healthcare workers through the lens of Spillover Theory and investigates impact of workplace violence on domestic stress with single and sequential mediation of workplace stress and domestic violence. Our findings of MEDTHREE analysis of time‐lagged data indicate that individuals who experience workplace violence are more likely to exhibit stress, which ultimately becomes a cause of domestic violence. The study highlights how spillover theory can help to explain how workplace violence can trigger violence and stress in the home environment. The research highlights the need for a support system and targeted interventions to address the issue of workplace violence to mitigate its spillover effects into domestic violence. With the help of the findings, the organisational decision makers can develop comprehensive strategies to mitigate the harmful consequences of the workplace violence to provide safe and healthy environment at work and home settings