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The purpose of this paper is to present competing risks models and show how dwell times can be applied to predict users’ online behavior. This information enables real-time personalization of web content.

This paper models transitions between pages based upon the dwell time of the initial state and then analyzes data from a web shop, illustrating how pages that are linked “compete” against each other. Relative risks for web page transitions are estimated based on the dwell time within a clickstream and survival analysis is used to predict clickstreams.

Using survival analysis and user dwell times allows for a detailed examination of transition behavior over time for different subgroups of internet users. Differences between buyers and non-buyers are shown.

As opposed to other academic fields, survival analysis has only infrequently been used in internet-related research. This paper illustrates how a novel application of this method yields interesting insights into internet users’ online behavior.

A key goal of any online retailer is to increase their customer conversation rates. Using survival analysis, this paper shows how dwell-time information, which can be easily extracted from any server log file, can be used to predict user behavior in real time. Companies can apply this information to design websites that dynamically adjust to assumed user behavior.

The method shows novel clickstream analysis not previously demonstrated. Importantly, this can support the move from web analytics and “big data” from hype to reality.

This study assessed the contribution of containerization to the development of Western Ports, Lagos Nigeria. The aim was to assess the influence of containerization on some indices of port development such as port infrastructure development, ship turnaround time, cargo dwell time and congestion. Questionnaire was used to gather information on the contribution of containerization to change in maritime trade in the country, the influence of containerization on terminal expansion, congestion, level of investment in container port infrastructure as well as the influence of such investment on container dwell time and ship turnaround time (TAT) and the competitiveness of container terminal within Nigeria port systems and with other developed container ports of the world. Secondary data used included statistics of reports of operations of Western Ports between 2000 and 2010 as reported by NPA, as well as reports of some selected ports derived from Containerization International Year Book, which were used in this study for the sake of global reference. Summary tables and ANOVA for the analysis of the data. Results revealed a significant contribution of containerization to maritime trade relative to the ports’ annual records but with no significant influence on ship turnaround time, cargo dwell time congestion which are determinants of port productivity and competitiveness. The study concluded that Western Ports have still not reaped gains of containerization and lacking in competitiveness when compared with other developed ports of the world.

Many e-commerce companies adopt a product customization platform offering various choices for customers to configure products to better satisfy their needs. However, a method to effectively measure customer satisfaction is lacking. This paper aims to investigate customers' perception of time in the online configuration process of customized products and seeks to propose time perception as the measurement of the effectiveness of online product customization.

An online laptop customization system was used in an empirical experiment to collect respondents' answers in a set of research questions. Regression and correlation analysis were conducted to investigate the factors affecting customers' satisfaction as well as the relationships with time perception.

The experimental results reveal several factors in customers' perception of time during the online product customization process. First, customers tend to overestimate the amount of time spent in a short-duration task but underestimate the amount of time spent in a long-duration task. Second, customers' perceptions of time are significantly correlated with their satisfaction with the configured products, and perceived time is moderately correlated with their satisfaction with the configuration process. Third, the difficulty of customization tasks and customers' motivation to process information also significantly affect customers' perceptions of time.

This paper advances the research on time perception by developing a new relative segmentation-based method to estimate the subjective perception of time. This study also makes several contributions to product customization research: the authors fill a research gap in the field of product customization by incorporating customers' perceptions of time into the measurement of customer satisfaction and by identifying the significant relationships among customers' perception of time, the ease of task selection, the customers' motivation to process information, and customers' satisfaction with customized products. These results aid in the design of online product customization systems.

Despite the extensive attention given to second and recreation homes in rural areas, their urban appearance has had only limited examination. This paper focuses on the trend as it is manifested in London and suggests urban second homes are an emerging phenomenon in contemporary cities. Drawing links between recreation homes and other aspects of mobility and dwelling in the global metropolis, the phenomenon is situated beyond local housing markets and placed in the context of globalization and urban restructuring. The part-time dwelling patterns it introduces are shown to challenge attempts to define and evaluate its spread. Additionally, the cross-spatial nature of urban second homes turns their owners into temporal occupants of several built environments simultaneously. They are thus defined both as a product and an emerging force in global cities, and as such beg unique attention. The phenomenon calls for the development of effective monitoring and tracking systems for addressing its development in cities. Lessons from the rural experience are used to propose policy approaches and the challenges posed by property market environment are emphasized. It is concluded that the transnational nature of urban second homes, and the inter-city connections they form and represent, call for cooperation between cities in addressing them. This may allow the creation of a global data-base and policy-bank as part of the challenge to maintain sustainable cities in the face of disappearing national borders.

The interruption event will seriously affect the normal operation of urban rail transit lines,causing a large number of passengers to be stranded in the station and even making the train stranded in the interval between stations. This study aims to reduce the impact of interrupt events and improve service levels.

To address this issue, this paper considers the constraints of train operation safety, capacity and dynamic passenger flow demand. It proposes a method for adjusting small loops during interruption events and constructs a train operation adjustment model with the objective of minimizing the total passenger waiting time. This model enables the rapid development of train operation plans in interruption scenarios, coordinating train scheduling and line resources to minimize passenger travel time and mitigate the impact of interruptions. Regarding the proposed train operation adjustment model, an improved genetic algorithm (GA) is designed to solve it.

The model and algorithm are applied to a case study of interruption events on Beijing Subway Line 5. The results indicate that after solving the constructed model, the train departure intervals can be maintained between 1.5 min and 3 min. This ensures both the safety of train operations on the line and a good match with passengers’ travel demands, effectively reducing the total passenger waiting time and improving the service level of the urban rail transit system during interruptions. Compared to the GA algorithm, the algorithm proposed in this paper demonstrates faster convergence speed and better computational results.

This study explicitly outlines the adjustment method of using short-turn operation during operational interruptions, with train departure times and station stop times as decision variables. It takes into full consideration safety constraints on train operations, train capacity constraints and dynamic passenger demand. It has constructed a train schedule optimization model with the goal of minimizing the total waiting time for all passengers in the system.

The purpose of this paper is to discuss the capability of finite element analysis (FEA) in performing the virtual thermal cycling reliability test to evaluate the reliability of solder joints in a ball grid array (BGA) package.

Thermal cycling test has been used to evaluate the reliability or fatigue life of the solder joints in BGA package using commercially available FEA software, ANSYS™. The effect of different temperature cycling condition is studied by applying different value of dwell time and ramp rate. Two types of analyses are used namely, the physics‐based analysis and the statistical‐based analysis. Two screening design methods namely, central composite design (CCD) and Box‐Behnken Matrix Design method are used to isolate the most important factors amongst six selected design variables. The optimization process is carried out using response surface methodology (RSM).

It is observed that changes in ramp rate produce significant effect in solder fatigue life than changes in dwell time but the dwell time at high temperature has a negligible contribution to solder fatigue life. It has been found that the thickness of the mold has a significant effect on the performance of the solder joint reliability (more than 50 percent) as compared to that from other factors. Besides, the effect of individual factor, the interaction among factors also changes the solder joint reliability. RSM based on Box‐Behnken Matrix design offers the highest characteristic solder joint fatigue life with a value of 2,861 cycles.

This paper provides a comprehensive method to evaluate the reliability of solder joints in terms of physics and statistical‐based analysis.

Safety training can effectively facilitate workers’ safety awareness and prevent injuries and fatalities on construction sites. Traditional training methods are time-consuming, low participation, and less interaction, which is not suitable for students who are born in Generation Z (Gen Z) and expect to be positively engaged in the learning process. With the characteristic of immersive, interaction, and imagination, virtual reality (VR) has become a promising training method. The purpose of this study is to explore Gen Z students’ learning differences under VR and traditional conditions and determine whether VR technology is more suitable for Gen Z students.

This paper designed a comparison experiment that includes three training conditions: VR-based, classroom lecturing, and on-site practice. 32 sophomore students were divided into four groups and received different training methods. The eye movement data and hazard-identification index (HII) scores from four groups were collected to measure their hazard-identification ability. The differences between the participants before and after the test were tested by paired sample t-test, and the differences between the groups after the test were analyzed by one-way Welch’s analysis of variance (ANOVA) test.

The statistical findings showed that participants under VR technology condition spent less time finding and arriving at the Areas of Interest (AOIs). Both the eye movement data and HII scores indicated that VR-based safety training is an alternative approach for Gen Z students to traditional safety training methods.

These findings contribute to the theoretical implications by proving the applicability of VR technology to Gen Z students and empirical implications by guiding colleges and universities to design attractive safety training lessons.

This study aims to examine the impact of the informational value of feedback choices (confirmatory versus critical feedback) on students’ performance, their choice to revise and the time they spend designing posters and reading feedback in a computer-based assessment game, Posterlet.

An empirical correlational study was conducted to collect the choices to seek confirmatory or critical feedback and to revise posters in a poster design task from 106 grade 8 students from a middle school in California via Posterlet.

The results of the study show that critical uninformative feedback is associated with students’ performance, and critical informative feedback is associated with their learning strategies (i.e. feedback dwell time and willingness to revise), while confirmatory informative feedback is negatively associated with both performance and learning strategies.

The study controlled the choice students were given regarding the valence of their feedback but not regarding the informational value of their feedback. Additionally, the study was conducted with middle-school students, and more research is needed to ascertain whether the results generalize to other populations.

The findings can be used to balance the design of the informational content of feedback messages to support student performance in an open-ended, creative design task. This study may also inform the design and implementation of agents (e.g. virtual characters) able to provide user-adaptive feedback for online interactive learning environments.

This study constitutes the first research to examine the informational value of feedback that is chosen rather than received, the latter being the prevalent model of delivering feedback in education.

A novel modelling approach is proposed to study ozone distribution and destruction in indoor spaces. The level of ozone gas concentration in the air, confined within an indoor space during an ozone-based disinfection process, is analysed. The purpose of this work is to investigate how ozone is distributed in time within an enclosed space.

A computational methodology for predicting the space- and time-dependent ozone concentration within the room across the consecutive steps of the disinfection process (generation, dwelling and destruction modes) is proposed. The emission and removal of ozone from the air volume are possible by means of a generator located in the middle of the room. This model also accounts for ozone reactions and decay kinetics, and gravity effect on the air.

This work is validated against experimental measurements at different locations in the room during the disinfection cycle. The numerical results are in good agreement with the experimental data. This comparison proves that the presented methodology is able to provide accurate predictions of the time evolution of ozone concentration at different locations of the enclosed space.

This study introduces a novel computational methodology describing solute transport by turbulent flow for predicting the level of ozone concentration within a closed room during a COVID-19 disinfection process. A parametric study is carried out to evaluate the impact of system settings on the time variation of ozone concentration within the space considered.

This paper aims to study the issues of adaptive fuzzy control for a category of switched under-actuated systems with input nonlinearities and external disturbances.

A control scheme based on sliding mode surface with a hierarchical structure is introduced to enhance the responsiveness and robustness of the studied systems. An equivalent control and switching control rules are co-designed in a hierarchical sliding mode control (HSMC) framework to ensure that the system state reaches a given sliding surface and remains sliding on the surface, finally stabilizing at the equilibrium point. Besides, the input nonlinearities consist of non-symmetric saturation and dead-zone, which are estimated by an unknown bounded function and a known affine function.

Based on fuzzy logic systems and the hierarchical sliding mode control method, an adaptive fuzzy control method for uncertain switched under-actuated systems is put forward.

The “cause and effect” problems often existing in conventional backstepping designs can be prevented. Furthermore, the presented adaptive laws can eliminate the influence of external disturbances and approximation errors. Besides, in contrast to arbitrary switching strategies, the authors consider a switching rule with average dwell time, which resolves control problems that cannot be resolved with arbitrary switching signals and reduces conservatism.