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The purpose of the study is to explore the dominant ideas in research on the management of time in construction. The focus of research has been to improve techniques for optimising the timing and sequence of activities.

A critical review of research on construction time management, challenging the typical focus. We examine the assumptions different authors make, underline the limitations of the dominant research approaches and examine the prospects for developing a new approach to researching these issues.

The dominant approach in literature focuses on unique activity traits in construction planning and measurable patterns between time-related variables. This assumes that time in construction can be managed by changing the way activities are calculated. These approaches have not been correlated with improvement in performance. Social practice theory may help to explain how programmes figure as one of many objects used during construction.

The focus is on reviewing indicative literature from key journals in construction management. The implication is that research is needed about how such documents are used in practice, which goes further than optimising plans in theory.

Future research could focus on understanding the context of construction planning practice and shift the debate from a focus on optimisation to practice.

An interpretivist approach with a focus on how tools such as planning documents are used on site. Social practice theory may provide a clearer explanation of the place of construction planning within the practice of construction management. This could provide solutions that deal effectively with stakeholder expectations around timely completion of construction projects.

The retail sector is not largely studied in Italy. The study offers a comparison between youth retail shift work in Milan and London. The aim of this paper is to contribute to the debate on the one hand on youth work and on the other hand to the debate on agency and structural factors in life planning, representation of the future and the transition to adulthood, observed in the United Kingdom's and Italian labour market. Even if the second one is a Southern European Country, these contexts are both characterised by a service-oriented economy and the widespread of precarious and flexible jobs.

Qualitative methods were used: one year of ethnographic observation, 50 interviews and two focus groups were carried out between 2015 and 2018 with retail workers and trade unionists. The contexts are Corso Buenos Aires in Milan, Italy, and Oxford Street in London, United Kingdom. Analysing young workers' discourses, the author identifies narratives that allow to grasp their present agency and imagined future.

Observing the crisis of the narrative (Sennett, 2020) allows to highlight the social consequences of working times on young workers' everyday life and future. The author argues that young workers struggle with the narrative of their present everyday life and the representation of the future. This relates to the condition of time alienation due to the flexible schedules and the fast pace of work in retail, both affecting the work-life balance.

The social consequences of flexible schedules in retail and fast fashion sector, which are new issues not yet sufficiently explored, are here investigated from the perspective of young workers. The study is focussed on the representations of young people working with customers in social and economic contexts characterised by flexible schedules and the deregulation of shop openings, the so-called 24/7 service society, not largely investigated in the sociological scientific literature, above all in the Italian context.

The purpose of this paper is to propose a smooth double-spline interpolation method for six-degree-of-freedom rotational robot manipulators, achieving the global C2 continuity of the robot trajectory.

This paper presents a smooth double-spline interpolation method, achieving the global C2 continuity of the robot trajectory. The tool center positions and quaternion orientations are first fitted by a cubic B-spline curve and a quartic-polynomial-based quaternion spline curve, respectively. Then, a parameter synchronization model is proposed to realize the synchronous and smooth movement of the robot along the double spline curves. Finally, an extra u-s function is used to record the relationship between the B-spline parameter and its arc length parameter, which may reduce the feed rate fluctuation in interpolation. The seven segments jerk-limited feed rate profile is used to generate motion commands for algorithm validation.

The simulation and experimental results demonstrate that the proposed method is effective and can generate the global C2-continuity robot trajectory.

The main contributions of this paper are as follows: guarantee the C2 continuity of the position path and quaternion orientation path simultaneously; provide a parameter synchronization model to realize the synchronous and smooth movement of the robot along the double spline curves; and add an extra u-s function to realize arc length parameterization of the B-spline path, which may reduce the feed rate fluctuation in interpolation.

This research examines what motivates professional truck drivers to engage in eco-driving by linking their self-reports with objective driving scores.

Theory of Planned Behavior (TPB) is illustrated in an embedded, single-case study of a Finnish carrier with 17 of its truck drivers. Data are obtained through in-depth interviews with drivers, their fuel-efficiency scores generated by fleet telematics and a focus group session with the management.

Discrepancies between drivers’ intentions and eco-driving behaviors are illustrated in a two-by-two matrix that classifies drivers into four categories: ideal eco-drivers, wildcards, wannabes and non-eco-drivers. Attitudes, subjective norms and perceived behavioral control are examined for drivers within each category, revealing that drivers’ perceptions did not always align with the reality of their driving.

This study strengthens the utility of TPB through data triangulation while also revealing the theory’s inherent limitations in elucidating the underlying causes of its three antecedents and their impact on the variance in driving behaviors.

Managerial insights are offered to fleet managers and eco-driving solution providers to stipulate the right conditions for drivers to enhance fuel-efficiency outcomes of transport fleets.

This is one of the first studies to give a voice to professional truck drivers about their daily eco-driving practice.

Feature selection is crucial for machine learning to recognize lane-change (LC) maneuver as there exist a large number of feature candidates. Blindly using feature could take up large storage and excessive computation time, while insufficient feature selection would cause poor performance. Selecting high contributive features to classify LC and lane-keep behavior is effective for maneuver recognition. This paper aims to propose a feature selection method from a statistical view based on an analysis from naturalistic driving data.

In total, 1,375 LC cases are analyzed. To comprehensively select features, the authors extract the feature candidates from both time and frequency domains with various LC scenarios segmented by an occupancy schedule grid. Then the effect size (Cohen’s d) and p-value of every feature are computed to assess their contribution for each scenario.

It has been found that the common lateral features, e.g. yaw rate, lateral acceleration and time-to-lane crossing, are not strong features for recognition of LC maneuver as empirical knowledge. Finally, cross-validation tests are conducted to evaluate model performance using metrics of receiver operating characteristic. Experimental results show that the selected features can achieve better recognition performance than using all the features without purification.

In this paper, the authors investigate the contributions of each feature from the perspective of statistics based on big naturalistic driving data. The aim is to comprehensively figure out different types of features in LC maneuvers and select the most contributive features over various LC scenarios.

The article introduces selected theoretical approaches to time and temporality relevant to the field of library and information science, and it briefly introduces the papers gathered in this special issue. A number of issues that could potentially be followed in future research are presented.

The authors review a selection of theoretical and empirical approaches to the study of time that originate in or are of particular relevance to library and information science. Four main themes are identified: (1) information as object in temporal perspectives; (2) time and information as tools of power and control; (3) time in society; and (4) experiencing and practicing time.

The paper advocates a thorough engagement with how time and temporality shape notions of information more broadly. This includes, for example, paying attention to how various dimensions of the late-modern time regime of acceleration feed into the ways in which information is operationalised, how information work is commodified, and how hierarchies of information are established; paying attention to the changing temporal dynamics that networked information systems imply for our understanding of documents or of memory institutions; or how external events such as social and natural crises quickly alter modes, speed, and forms of data production and use, in areas as diverse as information practices, policy, management, representation, and organisation, amongst others.

By foregrounding temporal perspectives in library and information science, the authors advocate dialogue with important perspectives on time that come from other fields. Rather than just including such perspectives in library and information science, however, the authors find that the focus on information and documents that the library and information science field contributes has great potential to advance the understanding of how notions and experiences of time shape late-modern societies and individuals.

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

Firstly, the bicycle model is adopted in the system modelling process. To improve the accuracy, the lateral stiffness of front and rear tire is estimated using the real-time yaw rate acceleration and lateral acceleration of the vehicle based on the vehicle dynamics. Then the constraint of input and output in the model predictive controller is designed. Soft constraints on the lateral speed of the vehicle are designed to guarantee the solved persistent feasibility and enforce the vehicle’s sideslip angle within a safety range.

The simulation results show that the proposed lateral stability controller based on the MPC algorithm can improve the handling and stability performance of the vehicle under complex working conditions.

The MPC schema and the objective function are established. The integrated active front steering/direct yaw moments control strategy is simultaneously adopted in the model. The vehicle’s sideslip angle is chosen as the constraint and is controlled in stable range. The online estimation of tire stiffness is performed. The vehicle’s lateral acceleration and the yaw rate acceleration are modelled into the two-degree-of-freedom equation to solve the tire cornering stiffness in real time. This can ensure the accuracy of model.

This paper aims to present a cooperative adaptive cruise control, called stable smart driving model (SSDM), for connected and autonomous vehicles (CAVs) in mixed traffic streams with human-driven vehicles.

Considering the linear stability, SSDM is able to provide smooth deceleration and acceleration in the vehicle platoons with or without cut-in. Besides, the calibrated Virginia tech microscopic energy and emission model is applied in this study to investigate the impact of CAVs on the fuel consumption of the vehicle platoon and traffic flows. Under the cut-in condition, the SSDM outperforms ecological SDM and SDM in terms of stability considering different desired time headways. Moreover, single-lane vehicle dynamics are simulated for human-driven vehicles and CAVs.

The result shows that CAVs can reduce platoon-level fuel consumption. SSDM can save the platoon-level fuel consumption up to 15%, outperforming other existing control strategies. Considering the single-lane highway with merging, the higher market penetration of SSDM-equipped CAVs leads to less fuel consumption.

The proposed rule-based control method considered linear stability to generate smoother deceleration and acceleration curves. The research results can help to develop environmental-friendly control strategies and lay the foundation for the new methods.

The purpose of this study is to address the extended travel time caused by dwelling time at stations for passengers on traditional rail transit lines. To mitigate this issue, the authors propose the “Non-stop” design, which involves trains comprised of modular vehicles that can couple and uncouple from each other during operation, thereby eliminating dwelling time at stations..

The main contributions of this paper are threefold: first, to introduce the concept of non-stop rail transit lines, which, to the best of the authors’ knowledge, has not been researched in the literature; second, to develop a framework for the operation schedule of such a line; and third, the author evaluate the potential of its implementation in terms of total passenger travel time.

The total travel time was reduced by 6% to 32.91%. The results show that the savings were more significant for long commutes and low train occupancy rates.

The non-stop system can improve existing lines without the need for the construction of additional facilities, but it requires technological advances for rolling stock.

To eliminate dwelling time at stations, the authors present the “Non-stop” design, which is based on trains composed of locomotives that couple and uncouple from each other during operation, which to the best of the authors’ knowledge has not been researched in the literature.