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Through application of multi-level structural equation modeling as the data analysis technique, the purpose of this paper is to analyze the group-level impacts on a couple’s food choices during travel at a coastal destination.

Researchers obtained 380 individual questionnaires from 190 mixed gender couples (who eat oysters) in Charleston and Beaufort County, South Carolina, USA. Data were collected from both members of the couple during their vacation. Due to missing data and normality issues 5 couples and 30 individuals were eliminated. The remaining data were analyzed with SPSS 21 and EQS 6.2 with advanced confirmatory factor analysis and multi-level (ML) regression techniques.

The study results indicated that while women have a more negative attitude than men toward oysters, their intention to eat oysters during vacation is not different from their partner. By detecting the interdependency of responses of individuals within a couple, this study revealed that a ML approach is a more powerful way to understand the decision-making process of couples. Additionally the difference in the results of single- and ML models showed that the latter approach lowers the chance of Type 2 error and provides more accurate results.

In tourism decision-making literature, the focus has been mostly on the individual despite the collectivistic nature of tourism activity. The current study is the first to analyze a couple’s decision-making process at the group level. Furthermore by collecting data from both members of the group during their vacation, this study has distinguished itself from previous studies.

The purpose of this paper is to investigate magneto-mechanical coupling occurring in magnetic resonance imaging (MRI) systems. The authors study influence of the strength of the background field on the coupling of mechanically isolated, conductive cylindrical structures and the so-called shields. This coupling has a strong impact on frequency-dependent thermal losses occurring in the shield structures which are of high importance in MRI systems.

In the investigations, numerical methods are applied. First, finite element methods taking into account the full magneto-mechanical coupling are used to investigate the coupled physical phenomena. As these calculations may be time-consuming, several approximate predictive methods are derived. Modal expansion factors and participation factors are based on combinations of structural eigenmode calculations and eddy current calculations using Biot–Savart representations of the dynamic gradient field. In addition, a parallelism factor expressed in terms of the shield vibrations is defined to measure the coupling between the distinct cylinders.

It is found that the strength of the background field strongly influences the coupling of the distinct shields, which strongly increases the parallelism of the shield vibrations. Furthermore, modal expansion and participation factors are significantly influenced, caused by frequency shifts due to magnetic stiffening and increased magnetic coupling.

The current work is limited to the modal expansions of a single shield. This needs to be extended in the future as comparison of modal expansion factors and finite element simulation indicate.

The defined factors estimating parallelism and modal participation in magneto-mechanical coupling are original work and studied for the first time.

The purpose of this study is to calculate the normal force of a two degree of freedom direct drive induction motor considering coupling effects based on an analytical model. Compared with the traditional single degree of freedom motor, normal force characteristics of two-degree-of-freedom direct drive induction motor (2DOFDDIM) is affected by coupling effect when the machine is in a helical motion. To theoretically explain the influence mechanism of coupling effect, this paper conducts a quantitative analysis of the influence of coupling effect on normal force based on the established analytical model of normal force considering coupling effect.

Firstly, the normal forces generated by 2DOFDDIM in linear motion, rotary motion and helical motion are investigated and compared to prove the effect of the coupling effect on the normal force. During this study, several coupling factors are established to modify the calculation equations of the normal force. Then, based on the multilayer theoretical method and Maxwell stress method, a novel normal force calculation model of 2DOFDDIM is established taking the coupling effect into account, which can easily calculate the normal force of 2DOFDDIM under different motions conditions. Finally, the calculation results are verified by the results of 3D finite element model, which proves the correctness of the established calculating model.

The coupling effect produced by the helical motion of 2DOFDDIM affects the normal force.

In this paper, the analytical model of the normal force of 2DOFDDIM considering the coupling effect is established, which provides a fast calculation for the design of the motor.

The purpose of this paper is to examine the relationship between the use of open innovation (OI) practices and firm performance, and the role of organizational mechanisms (OMs) (formalization and decentralization) as moderator variables.

The authors build a theoretical framework to define a set of hypotheses that are then verified in an empirical study. These theoretical propositions are tested by using the data gathered from a survey addressed to 244 firms in Spanish low- and medium-technology industries.

With regard to inbound practices, the practices oriented to cooperate with partners in a R&D context have a positive influence. The results show that outbound practices, either by direct generation of revenues from licensing payments or, more indirectly, through the indirect marketing and technical benefits that can stem from revealing have a positive effect on firm performance. Coupled practices, which are related to participation in clusters and innovation networks, have the highest impact on firm performance. In the industrial context examined, decentralization exerts a positive effect which enhances the effect of outbound practices meanwhile formalization reduces their positive effect.

This study helps practitioners in low- and medium-technology firms to determine which OI practices are most beneficial to firm performance and how formalization and decentralization can influence the relationship between OI and firm performance.

This study helps determine the influence of OI practices in terms of inbound, outbound and coupled types through an analysis of low- and medium-technology firms. The OI literature is enriched by the types herein of the role of OMs, which includes an analysis of how formalization and decentralization moderate the influence of OI practices on firm performance.

Entrepreneurial orientation (EO) is highly emerging in the management literature. However, recent studies highlight the necessity to associate with reflections on this theme, usually approached from an economic perspective, propositions also derived from relational approaches. This paper aims to investigate associations between EO and social networks, specifically about the still little explored relational coupling/decoupling theme.

This paper provides an empirical and qualitative study of religious entrepreneurs. A total of 18 pastors responsible for creating and leading independent neo-Pentecostal churches located in Belo Horizonte/Brazil, selected using the snowball technique, participated in this qualitative, case-study research. Two analysis categories guided data collection: pastors’ EO (behaviors suggestive of their innovativeness, proactivity, competitive aggressiveness, risk-taking and autonomy) and churches’ social framework (the resources and attributes that pastors obtain from their institutional structure).

The study concludes that pastors combine attributes representing their EO and their social structure in developing their religious endeavors.

Among the limitations are the restricted use of semi-structured interviews as a data collection source and the absence of data proving the churches’ performance.

The paper contributes by showing that entrepreneurs can influence the structure of their networks by using EO; proving that networks influence pastors’ EO; revealing recursivity between EO and networks; emphasizing a relational dimension of the EO construct and presenting new theoretical propositions that can be explored and tested in future investigations.

The purpose of this paper is to investigate the non-linear characteristics and stability of the rolling bearing–axle coupling system under the excitation of the axle/wheel speed of railway freight cars, so as to put forward a rationale for judging the vibration law and running stability of railway freight wagon.

Considering the effects of eccentric force of the railway wagon axle, the non-linear resistance of the wagon and non-linear support forces of axle box rolling bearings, a centralized mass model of rolling bearing-axle coupling system of railway freight wagon is presented on the basis of the theory of rotor dynamics and non-linear dynamics. Then the Runge-Kutta method is adopted to solve the non-linear response of the proposed system, and numerical simulation including bifurcation diagrams, axis trajectory curves, phase plane plots, Poincaré sections and amplitude spectras are analysed when the axle rotating speed is changed. Meantime, the relation curve between Floquet multiplier and axle rotating speed, which affects the stability of coupling system, is plotted by numerical method based on the Floquet theory and method.

The simulation results of the dynamic model reveal the abundant dynamic behaviour of the coupling system when the axle rotating speed changes, including single period, quasi period, multi-period and chaotic motion, as well as the evolution law from multi-period motion to chaotic motion. And especially, the bearing–axle coupling system is in stable state with a single period motion when the axle rotating speed changes from 410 rpm to 510 rpm, in which the running speed of railway freight wagon is changed from 62 km/h to 80 km/h, the vibration displacement of the coupling system in X direction is between 1.2 mm and 1.8 mm, and the vibration displacement of the coupling system in Y direction is between 1.0 mm and 1.45 mm. Meanwhile, the influence law of axle rotating speed on the stability is obtained by comparing the bifurcation diagram and Floquet multiplier graph of the coupling system.

The numerical simulation data obtained in this study can provide a theoretical evidence for designing the running speed of railway freight wagon, utilizing or controlling the non-linear dynamic behaviours of the proposed coupling system, and ensuring the stability of railway freight wagons.

Family holiday decision-making (FHDM) is a process composed of several stages. This paper aims to describe two objectives: to identify at each stage the roles in couples, the main decision-maker in the case of family holidays; and to determine the most influential variables.

To identify the roles played by the partners, a frequency analysis has been conducted, which provides a graphic representation of the so-called feasibility triangles. The technique selected to identify the variables that explained the decision structure was binary logistic regression. In total, 375 useful dyads of questionnaires were received.

Holidays follow a joint decision-making process in the initiation phase and in the final decision, while the search for information is carried out equally by either partner. The woman’s work situation, the type of destination travelled to and the difference in education levels between them are the variables that best explain how couples decide on their family holidays.

A better understanding of the FHDM process will help tourism companies to improve their marketing campaigns.

The characteristics of the sample composed of 375 couples whose members completed a questionnaire separately have allowed not have to rely on one response per household, which adds reliability to the results. This sample is higher than the one of many reference publications on the subject. Furthermore, this paper revealed differences between male and female perception.

According to the Stokes microcontinuum theorem and Christensen's stochastic model, the main objective of this paper is to theoretically predict the combined influences of couple stresses and surface roughness on the lubrication performance of journal‐bearing systems. To take account of the presence of both the surface roughness of bearings and the couple stress effect due to the lubricant containing the polar suspensions, the generalized stochastic non‐Newtonian Reynolds‐type equation is derived. Compared to the Newtonian‐lubricant smooth‐bearing case, the couple stress effects and the longitudinal roughness improve the load carrying capacity, and thus decrease the attitude angle and friction parameter, while the effect of transverse roughness is opposite to that of the longitudinal one in the journal‐bearing system.

Traditional continuum theory is usually applied in analysis of a gravity dam and its foundation; as we all know, both analytic and numerical solution of traditional theory imply that stress concentration around the dam heel and toe is very severe. However, stress condition of the dam and its foundation seems better for it can work normally for decades. Since concrete masses have macroscopic inhomogeneity, a new model has been built in order to simulate the mechanics behaviour of dam and its foundation rationally as the influence of inhomogeneity of the material has been taken into consideration. The purpose of this paper is to describe the application of the Cosserat granular model to analyze the stress condition of a mass concrete structure.

Granular model of Cosserat theory has been built and adopted to model the gravity, considering the influence of the couple‐stresses, due to the inhomogeneity of the material.

The Cosserat results have been compared with the traditional numerical solution, and the outcome indicates that the distributions of the stresses and displacements are rational, and the stress concentration around dam hell and toe is less severe and closer to the reality when Cosserat theory adopted.

The granular model based on Cosserat theory has been used in modelling a dam body for the first time; because the model can reflect the influence of the inhomogeneity, it is more suitable than traditional continuum model under this condition.

To control one of the joints during the actual movement of the hydraulically driven quadruped robot, all the other joints in the leg need to be locked. Once the joints are unlocked, there is a coupling effect among the joints. Therefore, during the normal exercise of the robot, the movement of each joint is affected by the coupling of other joints. This brings great difficulties to the coordinated motion control of the multi-joints of the robot. Therefore, it is necessary to reduce the influence of the coupling of the hydraulically driven quadruped robot.

To solve the coupling problem with the joints of the hydraulic quadruped robot, based on the principle of mechanism dynamics and hydraulic control, the dynamic mathematical model of the single leg mechanism of the hydraulic quadruped robot is established. On this basis, the coupling dynamics model of the two joints of the thigh and the calf is derived. On the basis of the multivariable decoupling theory, a neural network (NN) model reference decoupling controller is designed.

The simulation and prototype experiment are carried out between the thigh joint and the calf joint of the hydraulic quadruped robot, and the results show that the proposed NN model reference decoupling control method is effective, and this method can reduce the cross-coupling between the thigh and the calf and improve the dynamic characteristics of the single joint of the leg.

The proposed method provides technical support for the mechanical–hydraulic cross-coupling among the joints of the hydraulic quadruped robot, achieving coordinated movement of multiple joints of the robot and promoting the performance and automation level of the hydraulic quadruped robot.

On the basis of the theory of multivariable decoupling, a new decoupling control method is proposed, in which the mechanical–hydraulic coupling is taken as the coupling behavior of the hydraulic foot robot. The method reduces the influence of coupling of system, improves the control precision, realizes the coordinated movement among multiple joints and promotes the popularization and use of the hydraulically driven quadruped robot.