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The purpose of this paper is to develop an improved adhesion model to better reproduce the low adhesion condition of the anti-skid control for rail vehicles under braking condition.

In view of the low adhesion characteristics for rail vehicles under braking conditions, the Polach adhesion model was improved based on the sliding power and sliding energy. The wheel–rail low adhesion model suitable for braking condition was given. The analysis of braking anti-skid control under emergency braking condition was carried out through the co-simulation, and compared with the test data; the effectiveness and practicability of the improved low adhesion model were verified.

The results showed that the improved adhesion model is simple and efficient and the parameters involved are less, and it can be directly applied to the real-time simulation of anti-skid control in the process of train braking.

This paper can provide a theoretical reference for the reasons of change and improvement of adhesion between wheel and rail caused by the adjustment of braking force under anti-skid control, which can fulfill a need to the study of sliding energy on the contact surface, the removal effect of pollutants on the wheel–rail surface and the improvement and recovery of adhesion caused.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0244/

The performance of the classical car-following system is easily affected by external disturbances. To enhance the performance of the classical car-following model under sudden external disturbances, a novel car-following model is established to smooth traffic flow.

This paper proposed a Proportion Integration Differentiation (PID) control strategy based on classical control theory and developed a novel car-following model. The linear system theory and Laplace transform are used to derive a closed-loop transfer function. Then, the stability condition is obtained by using the Routh stability criterion and the small gain theorem. Finally, the validity and feasibility of the PID control strategy is proved by numerical simulations.

The analytic results and the numerical simulation results show that both the integration part and the differential part have the positive effect to suppress traffic oscillation efficiently; the collaboration of these two parts has more power to improve the stability of traffic flow. It means that the proposed model integrated with the PID control strategy has the ability of anti-interference and smooth traffic compared with the classical car-following model.

This paper introduces the PID control strategy into the classical car-following system, which enhances the stability of the system and also provides an efficient method for optimizing the traffic flow system.

Behavioral targeting has become a popular marketing strategy among brands as it enables advertisers to display ads to consumers based on their previous surfing behaviors. The purpose of this paper is to investigate the effectiveness of behaviorally targeted ads for luxury brands and to explore how and when behavioral targeting works.

A 2 (targeted vs non-targeted ads) ×2 (culture: China vs the Netherlands) between-subjects factorial design is conducted to test the hypothesis.

The result reveals that as for luxury brands, behavioral targeting can shorten the psychological distance and in turn lead to a more positive attitude toward the ad. However, the effect of behavioral targeting depends on the culture. In the Netherlands, behavioral targeting can enhance the attitude toward the ad by lowering the psychological distance. However, in China, these effects are mitigated.

This study contributes to the research of online luxury marketing. First, luxury brands should adapt their marketing strategy to different regional markets. In addition, luxury marketers should not worry about a shorter distance with consumers caused by the use of internet. A shorter distance does not mean to reduce an aura of mystery, but to build up a closer relationship with consumers. Luxury brands are not necessary to be aloof and supercilious like an indifferent robot. A closer relationship with consumers brings more positive effects.

The current research makes important contributions both to the scientific literature and to the luxury industry. First, this research reveals the effectiveness and underlying mechanisms of behavioral targeting for luxury brands and also compares the effectiveness of behavioral targeting in two cultures, which contributes to the current cross-cultural studies and international marketing research. Second, this study also helps luxury marketers to realize the importance of behavioral targeting and to know how and when they can use this new marketing strategy in a global environment.

This study integrates economic/ecology (eco)-attributes and performance to build a sustainable service supply chain management (SSCM) model.

This study proposes the use of the fuzzy Delphi method to screen for the less important attributes and applies a network data envelopment analysis to explore the hierarchical and eco-efficient network interrelationships. The causality and hierarchal eco-efficient model is acquired using a fuzzy decision-making trial and evaluation laboratory analysis

The findings are as follows: (1) the information and technology management process is derived by enhancing sustainable customer and supplier relationship management, and (2) the eco-efficient model is improved based on long-term relationships with suppliers – that is, synergistic suppliers improve the service chain quality and provide services in an appropriate and timely manner – and research and development coordination. The theoretical and managerial implications are discussed.

The eco-efficient model reveals that the sustainable customer relationship management process, sustainable supplier relationship management process and information and technology management process are the major causal attributes in the model.

The eco-efficient model must be based on (1) long-term relationships with suppliers, (2) synergistic suppliers to improve service chain quality, (3) the provision of services in a timely manner and (4) research and development coordination.

Prior studies neglect to build an ecological economy model using the efficiency causality model of hierarchical interrelationships. Traditional SSCM fails to involve the triple bottom line performance toward sustainability.

The rapid growth of m-commerce and mobile marketing has flooded the users with homogeneous contents that raise little user interest making the users' browsing pattern on these contents aimless free browsing. However, the interface that presents the mobile marketing contents triggers much user attention, especially the layout. Without significant usability defects, the layout poses influences on the user's aesthetic experience. Identifying the layout attributes that affect user aesthetic preference is critical to the design of mobile marketing interfaces since they influence users' interaction intention, cognitive process, and decision-making.

In this paper, 6 layout attributes that quantify the aesthetic design of the interface layout and 3 eye-movement indicators that connect to human aesthetic preference were identified through literature research. An eye-tracking experiment measuring the 3 eye-movement indicators on 6 pairs of interface layout materials corresponding to the 6 layout attributes was conducted. The experiment was designed to mimic the free browsing context in mobile marketing. The materials were divided into Liked/Disliked preference groups according to the response of the subjects. Analysis of indicators on materials between the L/D groups shows that the attributes of balance, centricity, density, simplicity, and symmetry affect user aesthetic preferences.

Analysis of the attribute value levels shows that balance, centricity, and density are responsible for addressing users' aesthetic preferences for a disliked interface layout. The study suggests an attribute set for quantitatively optimizing the aesthetic design of mobile marketing system interfaces and provides evidence for the visual attention and cognitive process under the free browsing context.

The study contributes to the field both theoretically and practically: (1) it provides support for optimizing the interface layout of mobile marketing systems quantitatively from the aesthetic perspective. (2) It promotes the cognitive attention theory by providing evidence for the cognitive process of interacting with mobile marketing interfaces from the perspective of visual attention and cognitive fluency. (3) It expands the objects of visual perception from traditional or symbolic artworks (such as logos) to the abstract visual stimuli of interface layout. (4) It suggests an optimization tool of five quantification layout attributes for mobile marketing businesses and platforms to aesthetically improve their marketing interfaces to improve user experiences.

Major changes of an aircraft configuration are conducted during the early design stage. It is important to include the airworthiness regulations at this stage while there is extensive freedom for designing. The purpose of this paper is to introduce an efficient design framework that integrates airworthiness guidelines and documentation at the early design stage.

A new design and optimization process is proposed that logically includes the airworthiness regulations as design parameters and constraints by constructing a certification database. The design framework comprises requirements analysis, preliminary sizing, conceptual design synthesis and loads analysis. A design certification relation table (DCRT) describes the legal regulations in terms of parameters and values suitable for use in design optimization.

The developed framework has been validated and demonstrated for the design of a Federal Aviation Regulations (FAR) 23 four-seater small aircraft. The validation results show an acceptable level of accuracy to be applied during the early design stage. The total mass minimization problem has been successfully solved while satisfying all the design requirements and certification constraints specified in the DCRT. Moreover, successful compliance with FAR 23 subpart C is demonstrated. The proposed method is a useful tool for design optimization and compliance verifications during the early stages of aircraft development.

The new certification database proposed in this research makes it simpler for engineers to access a large amount of legal documentation related to airworthiness regulations and provides a link between the regulation text and actual design parameters and their bounds.

The proposed design optimization framework integrates the certification database that is built of several types of legal documents such as regulations, advisory circulars and standards. The Engineering Requirements and Guide summarizes all the documents and design requirements into a single document. The DCRT is created as a summary table that indicates the design parameters affected by a given regulation(s), the design stage at which the parameter can be evaluated and its value bounds. The introduction of the certification database into the design optimization framework significantly reduces the engineer’s load related for airworthiness regulations.