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The purpose of this paper is to generate grinding trajectory of unknown model parts simply and efficiently. In this paper, a method of grinding trajectory generation of hybrid robot based on Cartesian space direct teaching technology is proposed.

This method first realizes the direct teaching of hybrid robot based on 3Dconnexion SpaceMouse (3DMouse) sensor, and the full path points of the robot are recorded in the teaching process. To reduce the jitter and make the speed control more freely when dragging the robot, the sensor data is processed by Kalman filter, and a variable admittance control model is established. And the joint constraint processing is given during teaching. After that, the path points are modified and fitted into double B-splines, and the speed planning is performed to generate the final grinding trajectory.

Experiment verifies the feasibility of using direct teaching technology in Cartesian space to generate grinding trajectory of unknown model parts. By fitting all the teaching points into cubic B-spline, the smoothness of the grinding trajectory is improved.

The whole method is verified by the self-developed TriMule-600 hybrid robot, and it can also be applied to other industrial robots.

The main contribution of this paper is to realize the direct teaching and trajectory generation of the hybrid robot in Cartesian space, which provides an effective new method for the robot to generate grinding trajectory of unknown model parts.

For autonomous vehicles, trajectory prediction of surrounding vehicles is beneficial to improving the situational awareness of dynamic and stochastic traffic environments, which is a crucial and indispensable element to realize highly automated driving.

In this paper, the overall framework consists of two parts: first, a novel driver characteristic and intention estimation (DCIE) model is built to indicate the higher-level information of the vehicle using its low-level motion variables; then, according to the estimation results of the DCIE model, a classified Gaussian process model is established for probabilistic vehicle trajectory prediction under different motion patterns.

The whole method is later applied and analyzed in the highway lane-change scenarios with the parameters of models learned from the public naturalistic driving data set. Compared with other traditional methods, the performance of this proposed approach is proved superior, demonstrated by the higher accuracy in the long prediction horizon and a more reasonable description of uncertainty.

This hierarchical approach is proposed to make trajectory prediction accurately both in the short term and long term, which can also deal with the uncertainties caused by the perception system or indeterminate vehicle behaviors.

This paper explores how organizational capabilities and path dependence affect the implementation of supply chain (SC) sustainability initiatives. Through the lenses of contingency and evolutionary theory, the paper addresses the underexplored supply chain dynamics that enhance or inhibit sustainability trajectories.

Using in-depth multi-case studies for theory elaboration, five supply chains were studied through open-ended interviews with SC members, secondary data collection and site visit observation. The design consists of a combination of deductive and inductive approaches to elaborate theory on supply chain dynamics and enhanced sustainability trajectories.

The empirical study shows that learning is a fundamental condition for supply chains as they implement sustainability initiatives, and that exploitation capabilities are more frequently used than exploration capabilities. Path dependence plays a role in the outcomes of supply chain sustainability initiatives, which are influenced by both path dependence and contingencies of the contexts in which these systems operate.

This paper puts forward five propositions that emerge from the literature and from the field study results. Although this is an exploratory research bounded by geographical limitations and the limited number of SC cases, the goal of elaborating theory may open up several promising avenues for future large-scale and longitudinal research studies.

By enhancing our understanding of the dynamics of supply chain sustainability trajectories, decision-makers, scholars and policy-makers can better understand how supply chains learn, how they employ SC member capabilities and how they deal with stakeholder resistance.

This paper extends supply chain sustainability theory by addressing the knowledge gap that exists with regard to understanding the dynamics of evolving supply chain sustainability trajectories. This paper sheds additional light on this important topic and contributes in multiple ways to the sustainable supply chain management literature.

The gender-gap reversal in education could have far-reaching consequences for marriage and family lives in the United States. This study seeks to address the following question: As women increasingly marry men with less education than they have themselves, is the traditional male breadwinner model in marriage challenged?

This study takes a life course approach to examine how educational assortative mating shapes trajectories of change in female breadwinning status over the course of marriage. It uses group-based trajectory models to analyze data from the National Longitudinal Survey of Youth 1979.

The results reveal substantial movement by wives in and out of the primary breadwinner role across marital years and great heterogeneity in female breadwinning trajectories across couples. In addition, educational assortative mating plays a role in shaping female breadwinning trajectories: Compared with wives married to men whose educational levels equal or exceed their own, wives married to men with less education than themselves are more likely to have a continuously high probability of being primary earners and are also more likely to gradually or rapidly transition into primary earners if initially they are not.

This study examines couples’ breadwinning arrangements over an extended period of time and identifies qualitatively distinct patterns of change in female breadwinning that are not readily identifiable using ad hoc, ex ante classification rules. The findings suggest that future research on the economics of marriage and couple relations in families would benefit from a life course approach to conceptualizing couples’ dynamic divisions of breadwinning.

Collaboration and acquisition have traditionally been observed as two alternative strategies when accessing external technologies. However, real option scholars have recently argued that firms can also engage in transitional technology sourcing trajectories where collaboration and acquisition are used as complementary strategies. While these real option scholars have identified factors that influence when partners are likely to shift from collaboration to acquisition, they remain silent on how such a transition can be effectively managed. Based on a multiple case study of four transitional technology sourcing trajectories between one new entrepreneurial and one established firm, this study therefore explores how the pre-acquisition collaboration stage and the post-acquisition integration are related to each other. Findings suggest that entrepreneurial companies may use the pre-acquisition collaboration stage as a period to evaluate the goodwill of the established partner. In addition, we point to the presence of pre-acquisition integration efforts and the extent of strategic convergence during the pre-acquisition collaboration stage as factors that substantially influence the success of the post-acquisition integration process in transitional governance trajectories.

The current air traffic management (ATM) operational approach is changing; “time” is now integrated as an additional fourth dimension on trajectories. This notion will impose on aircraft the compliance of accurate arrival times over designated checkpoints (CPs), called time windows (TWs). This paper aims to clarify the basic requirements and foundations for the practical implementation of this functional framework.

This paper reviews the operational deployment of 4D trajectories, by defining its relationship with other concepts and systems of the future ATM and communications, navigation and surveillance (CNS) context. This allows to establish the main tools that should be considered to ease the application of the 4D-trajectories approach. This paper appraises how 4D trajectories must be managed and planned (negotiation, synchronization, modification and verification processes). Then, based on the evolution of a simulated 4D trajectory, the necessary corrective measures by evaluating the degradation tolerances and conditions are described and introduced.

The proposed TWs model can control the time tolerance within less than 100 s along the passing CPs of a generic trajectory, which is in line with the expected future ATM time-performance requirements.

The main contribution of this work is the provision of a holistic vision of the systems and concepts that will be necessary to implement the new 4D-trajectory concept efficiently, thus enhancing performance. It also proposes tolerance windows for trajectory degradation, to understand both when an update is necessary and what are the conditions required for pilots and air traffic controllers to provide this update.

Posture adjustment plays an important role in spacecraft manufacturing. The traditional posture adjustment method, which has a large workload and is difficult to guarantee the quality of posture adjustment, cannot meet the requirements of modern spacecraft manufacturing. This paper aims to optimize the trajectory of posture adjustment, reduce the internal force of the posture adjustment mechanism and improve the accuracy of the system.

First, the measuring point is measured by a laser tracker and the position and posture of the cabin is solved. Then, Newton–Euler method is used to construct the dynamic model of the posture adjustment system (PAS) without internal force. Finally, the adjustment time is optimized based on Fibonacci search method and the trajectory of the cabin is fitted by the fifth order polynomial.

The simulation results show that, compared with the other trajectory planning methods, this method can effectively avoid the internal force of posture adjustment caused by redundant driving, and the trajectory of velocity and acceleration obtained are continuous, meeting the engineering constraints.

In this paper, a dynamic model of PAS without internal force is constructed. The trajectory planning of posture adjustment based on this model can improve the quality of cabin assembly.

The purpose of this paper is to argue for the institutionalisation of emergent forms of organisation in health and social care and offer a conceptual framework for this purpose.

Drawing on ethnographic research on the organising work of nurses and Translational Mobilisation Theory, this paper extends two classic Straussian sociological concepts – illness trajectory and articulation work – to conceptualise emergent organisation as Care Trajectory Management.

Failures of coordination are well-recognised threats to quality and safety and recent decades have witnessed an explosion of neoliberal technologies and governance arrangements designed to “measure and manage” these risks. Yet in a significant and growing proportion of health and social care provision successful service integration depends not on rational planning, but iterative negotiations and adjustments in response to contingencies. While ubiquitous in health and social care systems, these emergent forms of organisation lack legitimacy, the work involved is relatively invisible and practice is poorly served by prevailing management discourses.

The Care Trajectory Management Framework provides an alternative discourse and logic on which to develop strategies and technologies to support emergent organisational processes in acute and community care contexts.

The purpose of this paper is to investigate gender differences in employment status trajectories of young Europeans during their initial labour market experience, and the way in which they are affected by some labour market institutions.

The empirical analysis is based on EU-SILC longitudinal data (waves 2006–2012), and focusses on young people aged 16–34. Monthly information on self-declared employment statuses for 36 months is used to define “employment status trajectories”. Young people are observed in two different phases: the first three years after leaving education (first phase) and a three-year window, starting around four years after the end of education (2nd phase). Multinomial logit models are used to estimate the probability of following different trajectory types as a function of individual characteristics, macroeconomic conditions and institutional indicators.

Results show that, in the first phase, women and men face on average the same difficulties in entering the labour market. When controlling for the presence of children, non-mothers have higher chances than men to enter rapidly and successfully into the labour market, whereas young mothers have the same chances. In contrast, in the second phase women experience more fragmented pathways than men, even if they do not have children. A less stringent regulation on dismissals of employees with regular contracts could enhance women’s employment opportunities in the school-to-work transition, but it would have detrimental effects for both men and women in the subsequent years. On the contrary, a more stringent regulation on the use of temporary contracts would have beneficial effects for women, with no adverse effects for men.

The paper contributes to the literature in several ways. First, it takes a broader perspective on youth labour market integration by considering two phases of individuals’ initial working life. Second, it combines an explicit attention to the first “significant” employment experience with a focus on individual trajectories, by adopting a new method to group trajectories. Third, it shows how the effects of labour market institutions vary by gender, highlighting the importance of considering gender-specific consequences when discussing or adopting labour market reforms.