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The purpose of this study is to investigate the enhancement and suppression of heat transfer for hybrid nanofluids (Cu–Al2O3/water) in a square enclosure containing a thermal-conductive cylinder when the Lorentz force is applied to the hybrid nanofluids.

Since the inner conductive cylinder in present research has a complex geometry, an in-house meshless method, namely, the local radial basis function (LRBF) method, is applied to solve the 2 dimensional (2D) incompressible Navier–Stokes equation in the fluid domain and Fourier heat conduction equation in solid domain. The solid–fluid interface remains the physical continuity of temperature and heat flux. Only the Lorentz force is considered for the presence of the magnetic field. The conjugate natural convection is assumed to be steady, thus only fully developed heat exchange from the nanofluids to solid or vice versa is comprehensively investigated.

It can be concluded that Lorentz force plays a more significant role than hybrid nanofluids in enhancing/suppressing heat transfer when the orientation of magnetic field is the same to the x direction. The thermal conductivity ratio can dramatically change the isotherms and streamlines as well as the mean value of the Nusselt number, resulting in totally different heat transfer phenomena. The included angle of magnetic field also has a significant effect on the heat transfer rate when it changes from horizontal to vertical.

The constant thermo-physical properties of incompressible fluid and the 2D steady flow are considered in this study.

The conjugate MHD natural convection of hybrid nanofluids is numerically investigated by an in-house meshless LRBF method. The enhancement and suppression of heat transfer under the combined influence of the volume fraction of nanoparticles, Hartmann number and the thermal conductivity ratio are comprehensively investigated.

The purpose of this paper is to investigate whether the change of margin in Chinese futures markets has policy spillover effects.

The paper constructs a model based on Harzmark and on Chng, taking Chinese futures markets status quo as a single species and restrictions on foreign investment into consideration, introduces the assumptions of spillover effect of speculators, then obtains investor's demand function. Subsequently, the effects of Shanghai Futures Exchange's 11 instances of margin changing are analyzed.

The paper finds that in the Chinese futures market, margin changing has impact on the open interest (OI) and the speculator spillover effect is validated.

The irrational behavior of investors in markets is not taken into account in the model and data about spillover speculators were not directly available.

The paper usefully analyzes the effects of the Shanghai Futures Exchange's 11 instances of margin changing from 2000 to 2007 and examines the actual effects of margin‐changing policy, in the views of OI, trading volume and the externality, the results showing that margin changing has impact on investor structure and validates the existence of the assumed speculator spillover effect.

An interferogram is produced by modulating the difference between the extraordinary refractive index and the ordinary refractive index for photoelastic crystals in photoelastic-modulated Fourier transform spectrometers (PEM-FTs). Due to the influence of the refractive index dispersion characteristics on the maximum optical path difference of the interferogram, it is necessary to study wavelength calibration methods.

A wavelength calibration method for PEM-FTs was proposed based on the modulation principle of the photoelastic-modulated interferometer and the relationship between the maximum optical path difference and the refractive index difference. A 632.8 nm narrow-pulse laser was used as a reference source to measure the maximum optical path difference () of the interferogram, and the parameter was used to calculate the discrete frequency points in the frequency domain. To account for the influence of refractive index dispersion on the maximum optical path difference, the refractive index curve for the photoelastic crystal was used to adjust the discrete frequency coordinates.

The error in the reconstructed spectral frequency coordinates clearly decreased. The maximum relative error was 2.5%. A good solar absorption spectrum was obtained with a PEM-FT experimental platform and the wavelength calibration method.

The interferogram is produced by adjusting the difference between extraordinary refractive index and ordinary refractive index for the photoelastic crystal in the PEM-FTs. Given the wavelength dependence on the refractive indices, in view of the modulation principle of the photoelastic modulated interferometer, the relationship between the maximum optical path difference and the refractive index difference, the variation law of the refractive index of the photoelastic crystal and the process of spectral reconstruction is presented in this paper.

The size and complexity of China make the undertaking of research on the marketability of eco‐products in general a difficult task. However, it is assumed that cultural values significantly influence attitudes and behaviors. Therefore, this paper which uses a structural equation model, considers the extent to which Chinese people living in affluent cities in Southern China are found to have a low level of eco‐knowledge. It has identified that once the Chinese learn the hazards of eco‐unfriendly products to users and their family, they demonstrate a willingness to use greener products. The green consumption preferences also vary from product to product in China. Choosing the right eco‐product is the key to success. A case study related to the use of eco‐friendly insecticide has been used to demonstrate the marketability of eco‐products in China's affluent cities and is presented in this paper. The result may show a new horizon to green marketers.

The purpose of this paper is to accurately obtain the deformation of a hybrid robot and rapidly enable real-time compensation in friction stir welding (FSW). In this paper, a prediction algorithm based on the back-propagation neural network (BPNN) optimized by the adaptive genetic algorithm (GA) is presented.

Via the algorithm, the deformations of a five-degree-of-freedom (5-DOF) hybrid robot TriMule800 at a limited number of positions are taken as the training set. The current position of the robot and the axial force it is subjected to are used as the input; the deformation of the robot is taken as the output to construct a BPNN; and an adaptive GA is adopted to optimize the weights and thresholds of the BPNN.

This algorithm can quickly predict the deformation of a robot at any point in the workspace. In this study, a force-deformation experiment bench is built, and the experiment proves that the correspondence between the simulated and actual deformations is as high as 98%; therefore, the simulation data can be used as the actual deformation. Finally, 40 sets of data are taken as examples for the prediction, the errors of predicted and simulated deformations are calculated and the accuracy of the prediction algorithm is verified.

The entire algorithm is verified by the laboratory-developed 5-DOF hybrid robot, and it can be applied to other hybrid robots as well.

Robots have been widely used in FSW. Traditional series robots cannot bear the large axial force during welding, and the deformation of the robot will affect the machining quality. In some research studies, hybrid robots have been used in FSW. However, the deformation of a hybrid robot in thick-plate welding applications cannot be ignored. Presently, there is no research on the deformation of hybrid robots in FSW, let alone the analysis and prediction of their deformation. This research provides a feasible methodology for analysing the deformation and compensation of hybrid robots in FSW. This makes it possible to calculate the deformation of the hybrid robot in FSW without external sensors.

The purpose of this paper is to demonstrate how food waste management can affect both retail and distribution operators’ efficiency performance and their ability to create value. In particular, the paper shows how optimizing food waste management characterizes best practices and favors the development of sustainability.

Based on a survey of 196 outdoor market operators (including farmers and street food traders) from 27 outdoor markets, the authors analyzed unsold food/food wastage processes vis-à-vis the operators’ behavior and attitude. To provide accurate definitions of the satisfaction levels, a consumer perception survey was carried out, with a usable sample of 2,107 questionnaires. The efficiency performance was evaluated according to data envelopment analysis.

The results showed that farmers operate more efficiently than street food traders and that the traditional management of unsold food/food waste is an important competitive element in this sector.

The sample represents the Greater Turin Area in Italy, i.e., thus, limiting generalizability of the results. In addition, the variables analyzed were limited to certain aspects of selling processes and food waste management.

The results provide some indicators on how a more rational style of unsold food management can improve an operators’ performance and help make a social impact.

To the best of the authors’ knowledge, this is the first study that analyses outdoor market operators’ efficiency, based on the use of food waste as a variable affecting their performance.

Organisations often collaboratively seek ways such as partnerships, alliances and joint venture (JVs), to bridge gaps in their knowledge and capacity to provide goods or services. Infrastructure projects in Hong Kong often require clusters of resources, knowledge, skills and capabilities that are difficult to obtain in a single provider – it is often problematic for any single organisation to successfully complete these projects using only in‐house resources and knowledge. Thus, providers frequently form JVs and similar forms of relationships to undertake large‐scale infrastructure projects. While one motivation has been to spread financial and other risks, a strong motivation is to better capture learning, so that this hidden and intangible asset may be later applied to improve JV partners’ competitive advantage. Presents results from a pilot study that investigates the nature of the JV relationship, focusing upon the dimension of organisational learning intentions of JV representatives interviewed.

New business models, such as life‐cycle contracting, challenge the narrow and static understanding of contracts with hard and precise terms. The aim of this paper is to examine how flexibility could be incorporated into contracting processes.

The data of the paper have been gathered applying the triangular method; first, by interviewing key personnel participating in contracting at eight Finnish firms; second, examining contract and other documents of those companies; and third, studying earlier research on contracting practices. Theoretically, the paper is based on relational contract and proactive approaches to law on the one hand and on organizational studies based on new institutional economics on the other.

Flexibility is often introduced to contracts with relational methods, relying on good personal relationships between business partners or negotiation power and negotiation skills. Contract documents often do not contain mechanisms for dealing with contingencies, or “soft” contract terms. The paper finds the following reasons that may explain this. First, firms heavily rely on model contracts to develop their own templates and the lack of contract models in new business areas hinders firms to develop their templates. Second, unfamiliarity with using soft elements makes it difficult to use them. Additionally, in some cases firms may prefer using relational capability.

The findings need verification from further multidisciplinary empirical research.

The findings support firms in developing their contracting capabilities to meet the requirements of the changing business environment and gain competitive advantage from well‐organized contracting.

This paper is one of the first empirical studies comprising also the legal approach.

Based on the resource bricolage theory, we investigate the impact of proactive market orientation and responsive market orientation on firms’ disruptive green innovation. We also examine the impact of resource bricolage on disruptive green innovation and the mediating role of resource bricolage.

Quantitative data were collected from 232 firms in China. Structural equation modelling was used to test hypotheses.

The result show that proactive market orientation had positive effect on firm’s disruptive green innovation, whereas responsive market orientation had negative effect on firm’s disruptive green innovation. In addition, resource bricolage positively promotes firm’s disruptive green innovation. Resource bricolage played a mediating role between proactive market orientation and disruptive green innovation. Resource bricolage had a suppressing effect between responsive market orientation and disruptive green innovation.

This study makes up for the deficiency of the existing research on the relationship between market orientation and enterprise disruptive green innovation, improves the guidance mechanism of disruptive green innovation.

The purpose of this paper is to empirically analyze the role of differentiated margin system in leading investors' investing behavior and then optimize investor structure in futures markets.

Using economic experimental research method, this paper designs and conducts a futures market experiment according to experimental research's basic norms, thus acquiring needed and credible empirical data.

By analyzing the experimental data, it is found that compared with situations in futures markets that implement uniform margin system, investors' (especially speculators') futures open position and the ratio of their open position and futures turnover are both significantly higher, in futures markets that implement differentiated margin system. On the other hand, differentiated margin system has no effects on hedgers' futures turnover, but significantly reduces speculators' futures turnover.

The findings suggest that compared with uniform margin system, differentiated margin system is beneficial to effectively restrict both speculators' and hedgers' speculating behavior and lead hedgers' market participation.

In order to resolve the problem of unreasonable investor structure in China's futures market, i.e. lack of hedgers and over‐speculating, China's futures market's regulators should reform the margin system and adopt differentiated margin system to lead investors' rational behavior and optimize investor structure.

This paper empirically analyzes and verifies, for the first time, the roles of differentiated margin system in affecting investors' investing behavior. The futures market experiment designed and used in this study is a pioneering and exploratory experiment.