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The objective of this paper is to develop a fast modelling technique for predicting magneto-rheological fluid damper behaviour under impact loading applications.

The adaptive neuro-fuzzy inference system (ANFIS) technique was adopted to predict the behaviour of a magneto-rheological fluid (MRF) damper through experimental characterisation data. In this study, an MRF damper manufactured by Lord Corporation was used for characterisation using an impact pendulum test rig. The experimental characterisation was carried out with various impact energies and constant input currents applied to the MRF damper.

This research provided a fast modelling technique with relatively less error in predicting MRF damper behaviour for the development of control strategies. Accordingly, the ANFIS model was able to predict MRF damper behaviour under impact loading and showed better performance than the modified Bouc–Wen model.

This study only focused on modelling technique for a single type of MRF damper used for impact loading applications. It is possible for other applications, such as cyclic loading, random loadings and system identification, to be studied in future experiments.

Future researchers could apply the ANFIS model as an actuator model for the development of control strategies and analyse the control performance. The model also can be replicated in other industries with minor modifications to suit different needs.

This paper aims to better understand a firm’s market research function’s (MRF) roles and influences on the different uses of market research information (MRI) (instrumental, conceptual and symbolic) in the firm.

This study uses a mixed-methods design: In a qualitative study among marketing managers (n = 9) and market researchers (n = 10); different roles of a firm’s MRF are scrutinized. The quantitative study among corporate users of MRI (n = 235) tests a conceptual model on the MRF-related determinants of MRI uses, using structural equation modeling.

When the MRF exhibits methodological, market and business expertise and interacts with market research users, these features indirectly influence instrumental, conceptual, and symbolic uses, through MRI quality perceived by the users. The users’ knowledge of market research methods, the function’s integrity, top management support, and decentralized decision-making have various beneficial influences on the three uses of MRI.

Broadly speaking, this research expands the theoretical understanding of marketing-related organizational learning processes. It considers message, source, recipient, and context variables to explain changes in attitude and behavior, related to MRI uses.

Overall, corporations should use MRI more thoroughly. Treating the MRF as a strategic asset rather than just another internal service provider increases its value to the firm. Firms should thus bolster the MRF’s different roles, namely, internal colleague, service provider, customer representative, quality assurance, and knowledge broker.

This paper is the first to comprehensively analyze the MRF’s role in MRI generation and various uses. It identifies three expertise dimensions of the MRF to fully leverage the MRF’s value to the organization and empirically underscores theoretical writings on the MRF’s roles in the firm.

The purpose of this paper is to investigate the relationship between voluntary disclosure of a statement of management's responsibility for the financial reports (MRF) and earnings management, both accrual and real earnings management, in firms listed on the Stock Exchange of Thailand (SET).

The samples in this study are selected from listed companies on the SET in the year 2009. The multiple regression are used to test hypotheses.

The results show that the inclusion of a MRF has no association with both discretionary accrual and real earnings management activities (i.e. sales manipulation, a decrease in discretionary expenditures, and overproduction). The findings from the study reveal that firms with or without the MRF manipulate their earnings in a similar manner.

The sample for the study includes Thai listed firms in the year 2009 only. The small sample size may limit the validity of generalizations from these conclusions.

Based on the results, the regulators will know that the voluntary disclosure of management responsibilities on the financial reports is an ineffective tool to control earnings management.

Like Sarbanes-Oxley Act 2002, a disclosure of management responsibilities on the financial reports should be required by the Securities and Exchange Commission of Thailand.

Investors will know that firms with or without the MRF manipulate their earnings in a similar manner. The voluntary disclosure of an MRF in Thailand does not guarantee earnings quality.

In the magnetorheological fluid (MRF) sealing, a large amount of friction heat is generated in the fluid film with micron thickness due to the viscosity dissipation, which leads to seal failure and MRF deterioration. The purpose of this study is to investigate the mechanism of temperature rise of MRF film under the action of the three-field coupling of the flow field, temperature field and magnetic field.

The fluid film was simplified as a Couette flow in this work to simulate the temperature change in the sealing fluid film under different working conditions. The corresponding experiment for test the temperature rise was also carried out, and the temperature of the characteristic point of the stationary ring was measured to validate the model.

The results show that the temperature rise is mainly affected by the rotational speed, magnetic field strength and fluid film thickness. The magnetic field enhances the convective heat transfer in the MRF film. The thinner the fluid film, the more frictional heat generated. The MRF film reaches its maximum temperature at the contact with the end face of rotating ring due to frictional heat.

A method for temperature rise analysis of MRF fluid sealing films based on Couette flow is established. It is helpful for the study of liquid film frictional heat in MRF seals.

The purpose of this paper is to discuss the lean six sigma implementation process and its quantified benefits for the recycling industry. Specifically, the goals of the project were to improve the processes and increase capacity for a government operated material recovery facility (MRF) in Toledo, Ohio, USA.

The six sigma DMAIC methodology was utilized for this study. This included aligning and optimizing processes and the removal of process‐generated defects and errors.

After comparison of the current and future states of the MRF, it is found that by reducing non‐value added activities, productivity was increased by 7.3 percent for paper bales, 12.8 percent for commingled bales and 1.6 percent for old corrugated container (OCC) bales. The project generated over $65,000 in annual savings for the facility.

The findings are limited due to the focused nature of the case study and further cost‐benefit analysis can be carried out.

This paper may be useful to researchers and practitioners for understanding lean six sigma implementations and its derived benefits for the recycling industry and government operated processing facilities.

The paper is a real case study showing lean six sigma implementation and its benefits for the recycling industry; a field that has not been explored to a high degree.

The purpose of this paper is to carry out research on friction and wear behavior of pin-bushing with magnetorheological fluids (MRFs).

The oscillation friction characteristics of MRFs with a magnetic field are evaluated by a pin-bushing friction wear tester. The housing is adjusted to apply the magnetic field to MRFs. Experiments are carried out with and without a magnetic field, and the coefficient of friction and temperature on the contact interface are measured. The surfaces of the pin and bushing are also examined by a surface profilometer and an optical microscope before and after tests. The experiment results show a lower coefficient of friction is observed when a magnetic field is applied.

The temperature is lowest when grease is used. The case when a magnetic field is present shows the higher temperature. The coefficient of friction is higher than grease lubrication when an MRF is applied. The coefficient of friction of the pin-bushing is lowest with grease and highest when a magnetic field is present. The friction coefficient of grease and MRFs decreases as the load increases and remains stable after 3 kN is added. The roughness, surface profile and morphology of the pin show the best results when grease is used as compared with MRFs.

The tribology characteristic of pin-bushing with MRFs shows more deficiency than that with grease. Nevertheless, it is necessary to carry out the research on the friction and wear characteristics of a pin-bushing with MRFs, as it is expected to increase the load-carrying capacity when an MRF is applied to the pin-bush system. Better friction and wear characteristics could be achieved by enhancing the property of MRFs.

The purpose of this paper is to elaborate upon the mathematical model of coupled electromagnetic, fluid dynamic and motion phenomena that will allow for investigation of the magnetic hysteresis influence on the axial symmetry magnetorheological fluid (MRF) clutch operation.

To solve the partial differential equations describing magnetic vector and fluid velocity potential distributions in axial symmetry MRF electromechanical transducers the finite‐element methods have been applied. To solve model equations in the time domain, the time stepping method have been adopted. To introduce magnetic hysteresis phenomenon to presented approach the Jiles‐Atherton model have been applied. The physical properties of MRFs have been modeled by means of the Bingham model. Owing to high nonlinearity of the considered problem to solve obtained matrix equations systems the iterative Newton‐Raphson combined with the block over relaxation method have been applied.

The proposed model of coupled phenomena and the elaborated algorithm for solving the nonlinear model equations can be successfully applied in the analysis of transients in the MRF transducers taking fluid dynamics and magnetic hysteresis into account. Comparison of the measured and calculated clutch characteristics proves the model accuracy. Moreover, it has been shown that the residual magnetic flux density of the ferromagnetic core has significant impact on both to yield stresses forming in MRFs as well as the torque in disengagement clutch operation.

Development of the method for analysis of transients electromagnetic and fluid flow phenomena in MRF transducers taking magnetic hysteresis, electric circuits and motion into account. The presented approach is universal and can be successfully applied in other types of MRF electromechanical transducers such as clutch, brakes, rotary and linear dampers.

Commercial natural dyes are quite costly as manufacturers are to follow multi-step extraction and purification procedures for standardisation purposes. Upon cost comparison, they lose in the market to synthetic dyes. However, in the handicraft sector, reproducibility may be of lesser importance against cost. In the present study, a domestic method of dyeing silk with the aqueous extract of raw plant/tree components (flower, leave, bark and root) by using a natural mordant and alum will be described. Good dyebath exhaustion and washing and light fastness are observed for some of the natural colouring matters.

Financial statement fraud (FSF) committed by companies implies the current status of the companies may not be healthy. As such, it is important to detect FSF, since such companies tend to conceal bad information, which causes a great loss to various stakeholders. Thus, the objective of the paper is to propose a novel approach to building a classification model to identify FSF, which shows high classification performance and from which human-readable rules are extracted to explain why a company is likely to commit FSF.

Having prepared multiple sub-datasets to cope with class imbalance problem, we build a set of decision trees for each sub-dataset; select a subset of the set as a model for the sub-dataset by removing the tree, each of whose performance is less than the average accuracy of all trees in the set; and then select one such model which shows the best accuracy among the models. We call the resulting model MRF (Modified Random Forest). Given a new instance, we extract rules from the MRF model to explain whether the company corresponding to the new instance is likely to commit FSF or not.

Experimental results show that MRF classifier outperformed the benchmark models. The results also revealed that all the variables related to profit belong to the set of the most important indicators to FSF and that two new variables related to gross profit which were unapprised in previous studies on FSF were identified.

This study proposed a method of building a classification model which shows the outstanding performance and provides decision rules that can be used to explain the classification results. In addition, a new way to resolve the class imbalance problem was suggested in this paper.

Segmentation is an important topic in computer vision and image processing. In this paper, we sketch a scheme for a multiscale segmentation algorithm and prove its validity on some real images. We propose an approach to the model based on MRF (Markov Random Field) as a systematic way for integrating constraints for robust image segmentation. To do that, robust features and their integration in the energy function, which directs the process, have been defined. In this approach, the image is first transformed to different scales to determine which one fits better to our purposes. Then, it is segmented into a set of disjoint regions, the adjacent graph (AG) is determined and a MRF model is defined on the corresponding AG. Robust features are incorporated to the energy function by means of clique functions and optimal segmentation is then achieved by finding a labeling configuration that minimizes the energy function using Simulated Annealing.