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Accurate mapping is crucial for the positioning and navigation of mobile robots. Recent advancements in algorithms and the accuracy of LiDAR sensors have led to a gradual improvement in map quality. However, challenges such as lag in closing loops and vignetting at map boundaries persist due to the discrete and sparse nature of raster map data. The purpose of this study is to reduce the error of map construction and improve the timeliness of closed loop.

In this letter, the authors introduce a method for dynamically adjusting point cloud distance constraints to optimize data association (ODA-d), effectively addressing these issues. The authors propose a dynamic threshold optimization method for matching point clouds to submaps during scan matching.

Large deviations in LiDAR sensor point cloud data, when incorporated into the submap, can result in irreparable errors in correlation matching and loop closure optimization. By implementing a data association framework with double constraints and dynamically adjusting the matching threshold, the authors significantly enhance submap quality. In addition, the authors introduce a dynamic fusion method that accounts for both submap size and the distance between submaps during the mapping process. ODA-d reduces errors between submaps and facilitates timely loop closure optimization.

The authors validate the localization accuracy of ODA-d by examining translation and rotation errors across three open data sets. Moreover, the authors compare the quality of map construction in a real-world environment, demonstrating the effectiveness of ODA-d.

In modern China, sports and nationalism always have close connection, and nationalism is the important reason for the promotion of Chinese sports. However, the relationship between Chinese sports and nationalism in globalised China could be much more examined by academics, as well as its influencing factors. This chapter selects the Beijing 2008 Olympic Games as the context and representative three Chinese sports heroes in the period of globalisation to study. The findings show that in some extent, Beijing 2008 Olympic Games and three Chinese sports heroes represent the national image of China in the globalised world, also bearing the burden of washing away historical humiliation and pursuing national glory. Furthermore, it is manifested that China have a complex nationalism in the process of hosting the 2008 Olympic Games. Under the influence of mass media, market economy and sports professionalisation, nationalism still exists in Chinese sports, but people gradually start to reflect on the ‘Juguo Tizhi’, the traditional Chinese sports system and the concept of ‘winning glory for the nation’. The relationship between Chinese nationalism and sports shows the important implications of rapid Chinese sports development.

There is evidence that both hypnotherapy and virtual reality (VR) can be helpful in reducing perceived stress in the general population. This is a feasibility and acceptability trial of an intervention combining hypnotherapy and VR to establish its acceptability in students. This study aims to establish whether students found the experience acceptable, described any adverse effects and whether they reported feeling calmer after the experience.

The study was testing the hypothesis that students would attend the sessions and find the experience acceptable. A secondary hypothesis was that preliminary qualitative and quantitative evaluation of measures of stress and wellbeing would signal potential improvements.

All participants completed all three sessions. No side effects were reported. Visual analogue scales recorded each day assessing the immediate effect improved. At the end of the intervention, there was an increase in wellbeing of 2.40 (95% CI: 1.33, 3.53, p = 0.006), and a decrease in depression of 0.73 (95% CI: 0.40, 1.07, p = 0.010), reflecting large effect sizes of 0.76 and 0.83, respectively. Qualitative feedback was generally very positive.

This study is small with just 15 students and was over a short period of time. The recruitment method meant there was no way to establish whether the volunteer students were representative of the general student population in terms of mental wellbeing. There was no control arm.

The preliminary results suggest that a larger controlled trial is justified.

This VR experience may have benefit to university students and to the wider population.

This described the evaluation of a novel intervention for perceived stress combining hypnotherapy and virtual reality in a group of healthcare students, with promising results suggesting further evaluation is needed.

Drawing on interviews with two types of essential workers – wound clinicians and care workers – the chapter examines stigma management in dirty care work through the lens of emotion management. The study combines two dimensions of dirty work: physical taint in relation to bodywork and social taint linked to working in close proximity to socially stigmatized clients. Hence, stigma management extends to dealing with the physically and socially dirty features of essential care work. In addition, the authors’ assessment of social stigma includes how essential care workers also sought to alleviate the social stigma encountered by their clients. In so doing, the authors extend the literature on dirty work to identify how emotion management skills are central to the stigma management strategies of the essential care workers in this study. The authors demonstrate how both groups deal with their stigma by emphasizing the emotion management skills in ‘doing’ dirty work and in the ‘purpose’ of this work, which includes acknowledging how the authors attempt to address the social taint encountered by their clients. Additionally, by comparing two occupations with different contexts and conditions of work, the authors show how complex emotion management skills are gendered in care work to expand the understanding of gender and stigma management. Furthermore, these emotion management skills emanate from the deep relational work with clients rather than through occupational communities. The authors argue that by focussing on emotion management, the hidden skills of dirty work in gendered care work are illuminated and contribute to contemporary debates about whether stigma can be overcome.

This chapter argues that the National Basketball Association (NBA) and American mainstream sporting media produce and mediate a representation of India as underdeveloped and as an unmodern subject/nation as a way to enter the Indian basketball marketplace. The chapter emphasizes that the NBA produces the attendant discourse of the ‘white saviour’ through a multi-pronged process. The chapter shows how it draws upon the legacies of British colonialism, along with the expansion of US imperialism, to construct India in particular racialised ways as backward, unmodern, and not cosmopolitan. In this respect, Black NBA players’ modes of basketball reach India as part of the racialisation of Indian basketball. Finally, the chapter engages with the larger global circuits of race and racialisation to understand how India is then imagined within the US sporting landscape. This chapter underscores the capitalist desires of the NBA alongside the desires of South Asian Americans for an Indian basketball hero. Both desires, institutional and personal, showcase racialisation at work. The NBA uses the language and performance of Judeo-Christian modernity through NBA players in India to racialise Indians as in need of NBA mentorship and upliftment. On other hand, diasporic Indians in the US dream of an Indian NBA player as a way to unravel, destabilise, and challenge their racialisation as hypo-masculine subjects. These competing forms of racialisation provide important information on the global flows of capital, desire, and sport.

Visual feedback control is a promising solution for robots work in unstructured environments, and this is accomplished by estimation of the time derivative relationship between the image features and the robot moving. While some of the drawbacks associated with most visual servoing (VS) approaches include the vision–motor mapping computation and the robots’ dynamic performance, the problem of designing optimal and more effective VS systems still remains challenging. Thus, the purpose of this paper is to propose and evaluate the VS method for robots in an unstructured environment.

This paper presents a new model-free VS control of a robotic manipulator, for which an adaptive estimator aid by network learning is proposed using online estimation of the vision–motor mapping relationship in an environment without the knowledge of statistical noise. Based on the adaptive estimator, a model-free VS schema was constructed by introducing an active disturbance rejection control (ADRC). In our schema, the VS system was designed independently of the robot kinematic model.

The various simulations and experiments were conducted to verify the proposed approach by using an eye-in-hand robot manipulator without calibration and vision depth information, which can improve the autonomous maneuverability of the robot and also allow the robot to adapt its motion according to the image feature changes in real time. In the current method, the image feature trajectory was stable in the camera field range, and the robot’s end motion trajectory did not exhibit shock retreat. The results showed that the steady-state errors of image features was within 19.74 pixels, the robot positioning was stable within 1.53 mm and 0.0373 rad and the convergence rate of the control system was less than 7.21 s in real grasping tasks.

Compared with traditional Kalman filtering for image-based VS and position-based VS methods, this paper adopts the model-free VS method based on the adaptive mapping estimator combination with the ADRC controller, which is effective for improving the dynamic performance of robot systems. The proposed model-free VS schema is suitable for robots’ grasping manipulation in unstructured environments.

High levels of child obesity alongside rising stunting and the absence of a coherent food policy have deemed UK’s food system to be broken. The National Food Strategy (NFS) was debated intensely in media, with discussions on how and who should fix the food system.

Using a mixed methods approach, the authors conduct framing analysis on traditional media and sentiment analysis of twitter reactions to the NFS to identify frames used to shape food system policy interventions.

The study finds evidence that the media coverage of the NFS often utilised the tropes of “culture wars” shaping the debate of who is responsible to fix the food system – the government, the public or the industry. NFS recommendations were portrayed as issues of free choice to shift the debate away from government action correcting for market failure. In contrast, the industry was showcased as equipped to intervene on its own accord. Dietary recommendations made by the NFS were depicted as hurting the poor, painting a picture of helplessness and loss of control, while their voices were omitted and not represented in traditional media.

British media’s alignment with free market economic thinking has implications for food systems reform, as it deters the government from acting and relies on the invisible hand of the market to fix the system. Media firms should move beyond tropes of culture wars to discuss interventions that reform the structural causes of the UK’s broken food systems.

As traditional media coverage struggles to capture the diversity of public perception; the authors supplement framing analysis with sentiment analysis of Twitter data. To the best of our knowledge, no such media (and social media) analysis of the NFS has been conducted. The paper is also original as it extends our understanding of how media alignment with free market economic thinking has implications for food systems reform, as it deters the government from acting and relies on the invisible hand of the market to fix the system.