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The purpose of this study is to solve NP-Hard drone routing problem for the last-mile distribution. This is suitable for the multi-drones parcel delivery for the various items from a warehouse to many locations.

This study conducts as a mission assignment of the single location per flight with the constraint satisfactions such as various payloads in weight, drone speeds, flight times and coverage distances. A genetic algorithm is modified as the concurrent heuristics approach (GCH), which has the knapsack problem dealing initialization, gene elitism (crossover) and gene replacement (mutation). Those proposed operators can reduce the execution time consuming and enhance the routing assignment of multiple drones. The evaluation value of the routing assignment can be calculated from the chromosome/individual representation by applying the proposed concurrent fitness.

This study optimizes the total traveling time to accomplish the distribution. GCH is flexible and can provide a result according to the first-come-first-served, demanded weight or distance priority.

GCH is an alternative option, which differs from conventional vehicle routing researches. Such researches (traveling time optimization) attempt to minimize the total traveling time, distance or the number of vehicles by assuming all vehicles have the same traveling speed; therefore, a specific vehicle assignment to a location is neglected. Moreover, the main drawback is those concepts can lead the repeated selection of best quality vehicles concerning the speed without considering the vehicle fleet size and coverage distance while this study defines the various speeds for the vehicles. Unlike those, the concurrent concept ensures a faster delivery accomplishment by sharing the work load with all participant vehicles concerning to their different capabilities. If the concurrent assignment is applied to the drone delivery effectively, the entire delivery can be accomplished relatively faster than the traveling time optimization.

This study aims to offer a conceptual framework that elaborates on how tourists’ perception of contradictory features in reviews’ factuality and comprehension – within a single hotel review and across multiple hotel reviews – trigger attitude ambivalence and psychological discomfort, which determine their behaviors – choice deferral and hotel booking intentions. It also investigates the moderating role of anticipated conflicting reactions (ACRs) through contradictory features on consumers’ attitude ambivalence.

Using a Chinese setting, researchers collected data from 524 inbound tourists who were the consumers of hotels in Beijing. The study used IBM Amos 23.0 to test measurement and structural models for the proposed relationships. It also used PROCESS macro 3.4 for the moderation analysis.

The findings reveal a positive association between contradictory features in reviews and the resulting ambivalence that affects consumers’ discomfort and leads to the decision to defer the choice of hotel. Conversely, consumers’ discomfort has a positive impact on the hotel booking intentions. ACRs have positive moderating effects on the associations between contradictory features and consumers’ attitude ambivalence.

By investigating the contradictory features in hotel reviews, this study extends the body of research on dual information processing (i.e. the heuristic–systematic model) and the literature on service management, psychological behaviors, travel intermediaries and hotel firms. Future research directions are recommended for tourism and hospitality researchers.

With the continuous technological development of automated driving and expansion of its application scope, the types of on-board equipment continue to be enriched and the computing capabilities of on-board equipment continue to increase and corresponding applications become more diverse. As the applications need to run on on-board equipment, the requirements for the computing capabilities of on-board equipment become higher. Mobile edge computing is one of the effective methods to solve practical application problems in automated driving.

In this study, in accordance with practical requirements, this paper proposed an optimal resource management allocation method of autonomous-vehicle-infrastructure cooperation in a mobile edge computing environment and conducted an experiment in practical application.

The design of the road-side unit module and its corresponding real-time operating system task coordination in edge computing are proposed in the study, as well as the method for edge computing load integration and heterogeneous computing. Then, the real-time scheduling of highly concurrent computation tasks, adaptive computation task migration method and edge server collaborative resource allocation method is proposed. Test results indicate that the method proposed in this study can greatly reduce the task computing delay, and the power consumption generally increases with the increase of task size and task complexity.

The results showed that the proposed method can achieve lower power consumption and lower computational overhead while ensuring the quality of service for users, indicating a great application prospect of the method.

This study presents a systematic literature review (SLR) of the interdisciplinary literature on drones in last-mile delivery (LMD) to extrapolate pertinent insights from and into the logistics management field.

Rooting their analytical categories in the LMD literature, the authors performed a deductive, theory refinement SLR on 307 interdisciplinary journal articles published during 2015–2022 to integrate this emergent phenomenon into the field.

The authors derived the potentials, challenges and solutions of drone deliveries in relation to 12 LMD criteria dispersed across four stakeholder groups: senders, receivers, regulators and societies. Relationships between these criteria were also identified.

This review contributes to logistics management by offering a current, nuanced and multifaceted discussion of drones' potential to improve the LMD process together with the challenges and solutions involved.

The authors provide logistics managers with a holistic roadmap to help them make informed decisions about adopting drones in their delivery systems. Regulators and society members also gain insights into the prospects, requirements and repercussions of drone deliveries.

This is one of the first SLRs on drone applications in LMD from a logistics management perspective.

The purpose of this paper is to evaluate the usability of the National Library of Turkey website developed for all citizens in the country to retrieve information available in a wide range of areas.

The evaluation performed by 57 undergraduate university students involved the identification and analysis of usability problems in the selected website. The assessment process was mainly based on Nielsen’s Heuristics. The data obtained in the evaluation process were enriched using the System Usability Scale (SUS) and the Net Promoter Score (NPS) to conduct a more detailed analysis.

The participants identified many usability problems concerning the evaluated website and considered it as having low usability characteristics. The most violated heuristic item was found to be “consistency and standards” whereas the least violated heuristic item was “match between system and the real world.” The total number of the usability problems in heuristic evaluation correlated significantly and negatively with the SUS and the NPS results indicating that the more participants identified usability problems, the less they considered the website as usable and recommendable.

The participants were not usability experts, however they were selected from among the students who received the Human Computer Interaction course to ensure that they had sufficient information and experience concerning the evaluation of a website with heuristics. Besides, the study was limited to a small number of university students. The implication is that results of this study have potential to guide libraries, which plan to adapt themselves to the digital world by delivering web services, by addressing critical points influencing users’ points of views toward library websites and their usability evaluation result.

Depending on the changes in user habits regarding the retrieval of information, libraries have made considerable investments in web technologies to meet their users’ demands, and recently, digital libraries have begun to take over physical libraries. Users always need to perform tasks efficiently, effectively and satisfactorily when using websites. As one of the most crucial sources of digital materials, library websites are expected to have usable characteristics that satisfactorily meet user requirements. Therefore, the practical implication is that the findings of the study will guide designers, developers and practitioners in the development of library websites.

In the context of usability evaluation of digital libraries, this is the first study to analyze effects of usability problems identified by users during the heuristic inspection on their overall evaluation score and willingness to recommend the website to their friends or colleagues.

The purpose of this paper is to explore consumer thinking about nutrition decisions and how firms can use consumers’ awareness of the links between nutrients and health generated by public health messages to market products, including ones, which have little nutritional value. We approach this issue by tracking the development of public health messages based on scientific research, dissemination of those messages in the popular press, and use of nutrition claims in food advertisements to assess whether firms are timing the use of nutrition claims to take advantage of heuristic-based decision-making. Our findings suggest that the timing of the development of nutrition information, its dissemination in the press, and use in advertising accords well with a heuristic processing model in which firms take advantage of associations between nutrient information and health in their advertisements. However, the demonstrated relationships may not be causal. Further research will be needed to provide stronger and more comprehensive evidence regarding the proposed message hijacking process. If the message hijacking framework is borne out: (1) simple overall health rating scales could significantly improve consumer decision-making, (2) the impact of misleading advertisements could be mitigated by encouraging a multidimensional view of nutrition, and (3) more intensive regulation of product labeling could limit the impact of hijacked messages.

Overall, this paper considers a novel hypothesis about the impact of public health messages on nutrition and health.

“Concurrent sourcing” is a term used by Parmigiani to describe the phenomenon where a firm simultaneously buys and makes the same good or service. The purpose of this paper is to develop propositions that suggest how concurrent sourcing affects performance.

Based on transaction cost, agency, neoclassical economic, knowledge‐based, and resource‐based theory, it is proposed to show how concurrent sourcing affects performance.

The paper argues that concurrent sourcing improves performance when firms face a combination of volume uncertainty, technological uncertainty, performance uncertainty, non‐decomposability, transaction‐specific investments, and strong internal and external capabilities.

The paper maps the relationships between concurrent sourcing and performance and discusses how these relationships can be modelled. The propositions and discussion offer researchers a starting‐point for further research.

The propositions that are developed suggest that managers should consider using concurrent sourcing when they face problems caused by volume uncertainty, technological uncertainty, performance uncertainty, non‐decomposability, and asset specificity. Concurrent sourcing can also be a way to exploit both strong internal capabilities and external suppliers' strong capabilities.

The main contribution is a number of propositions, explanations, and discussions regarding how concurrent sourcing affects performance of the market and the hierarchy.

Gradual phasing out of manual methods through sequential substitution of machines may well represent the only viable manufacturing strategy option for many job shops particularly in developing countries. For such job shop projects with limited capital, investment in buildings and machines needs to be phased so as to benefit from added capital from reinvested earnings. Describes a dynamic integer model suitable for such investment scheduling. Suggests that the model was solved with a readily implementable heuristic which employs suitable decision rules for scheduling machinery purchases and factory space construction in modular units. The model will find ready application in emerging job shop projects of many developing countries.

The target of this research is to develop a mathematical model which combines the Resource-Constrained Multi-Project Scheduling Problem (RCMPSP) and the Multi-Skilled Resource-Constrained Project Scheduling Problem (MSRCPSP). Due to the importance of resource management, the proposed formulation comprises resource leveling considerations as well. The model aims to simultaneously optimize: (1) the total time to accomplish all projects and (2) the total deviation of resource consumptions from the uniform utilization levels.

The K-Means (KM) and Fuzzy C-Means (FCM) clustering methods have been separately applied to discover the clusters of activities which have the most similar resource demands. The discovered clusters are given to the scheduling process as priori knowledge. Consequently, the execution times of the activities with the most common resource requests will not overlap. The intricacy of the problem led us to incorporate the KM and FCM techniques into a meta-heuristic called the Bi-objective Symbiosis Organisms Search (BSOS) algorithm so that the real-life samples of this problem could be solved. Therefore, two clustering-based algorithms, namely, the BSOS-KM and BSOS-FCM have been developed.

Comparisons between the BSOS-KM, BSOS-FCM and the BSOS method without any clustering approach show that the clustering techniques could enhance the optimization process. Another hybrid clustering-based methodology called the NSGA-II-SPE has been added to the comparisons to evaluate the developed resource leveling framework.

The practical importance of the model and the clustering-based algorithms have been demonstrated in planning several construction projects, where multiple water supply systems are concurrently constructed.

Reviewing the literature revealed that there was a need for a hybrid formulation that embraces the characteristics of the RCMPSP and MSRCPSP with resource leveling considerations. Moreover, the application of clustering algorithms as resource leveling techniques was not studied sufficiently in the literature.

Puzzle-based storage is a novel approach enabling very dense storage. Previous analytical studies have focussed on retrieval time when one or more usable escort locations (empty slots) are located near the system input/output location, and on simulation results for more complex situations. The purpose of this paper is to extend analytical results to determine retrieval time performance when multiple escorts are randomly located within the system.

Closed-form expressions for retrieval time are developed and proven for cases in which the number of free, randomly placed escorts is equal to one or two. Heuristics with associated worst case bounds are proposed for larger numbers of free escorts.

Puzzle-based storage systems are practical and viable ways to achieve storage density, but retrieval time is heavily dependent upon suitable use of escort locations. Analytical and heuristic methods developed within the paper provide worst-case retrieval time performance in a variety of settings.

As the number of free, randomly located escorts increases, optimal analytical solutions are difficult to obtain. Heuristics provide viable retrieval strategies in these situations, and worst-case bounds are relatively easily developed.

The primarily contribution of this paper is to make theoretical extensions of optimal methods for puzzle-based storage systems. It motivates additional research in multiple-escort systems and provides insights that should prove useful for the development of 3-dimensional puzzle-based systems and for systems in which concurrent item movement is permitted.