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A typical photovoltaic grid-connection power system usually consists of multi-stage converters to perform multiple functions simultaneously. To simplify system configuration, reduce cost and improve conversion efficiency, this paper aims to develop a buck–boost-type inverter. The proposed inverter has both step-up and step-down functions, so that it is suitable for applications with wide voltage variation. As only one power switch operates with high frequency at one time, switching losses can significantly be reduced.

A step-up/down inverter is developed by adopting a buck-interleaved buck–boost (BuIBB) DC-DC converter and connecting with an H-bridge unfolding circuit with line-commutated operation.

The proposed circuit can work functionally as either a buck-type or boost-type inverter, so that partial energy can be directly delivered to output to improve efficiency. The input current is shared by two inductors, leading to the reduction of current stresses.

To apply the proposed inverter to micro-inverter applications in the future, developing a step-up/down inverter with a higher conversion ratio will be considered.

A laboratory prototype is built accordingly to verify the feasibility of the proposed inverter. The experimental results are presented to show the effectiveness.

This paper proposes a step-up/down inverter by using the BuIBB converter, which is innovatively studied.

This study aims to gain insight on evaluation of cause-related marketing (CrM) campaigns by the millennial with focus on skepticism, brand identity and patronage intention.

To attain the above objective a conceptual model was developed and tested using structural equation modeling and confirmatory factor analysis.

The finding suggests that sub-segments exist among millennial segments. They can be classified into hedonic, utilitarian, individualistic and collectivists. Compared to utilitarian and individualistic customers hedonic and collectivists were found to evaluate CrM campaign more favorably. Utilitarian and individualistic depict skepticism toward CrM campaign.

The in-depth knowledge gained about millennials is expected to benefit academicians and marketers alike. Academicians will be enriched by the knowledge of the micro-segments that exists among the millennial and how that had differential impact on their skepticism while evaluating CrM campaign. The marketers involved in the designing and implementation of the CrM campaign will be benefited from the in-depth knowledge of segments with lower and higher levels of skepticism. Such knowledge gained will help them develop more effective CrM campaign.

One of the contributions of the present study is that it extends the existing knowledge about millennials, particularly in the context of CrM campaign evaluation integrating it with other important variables such as skepticism, brand identity and patronage intention.

In recent years, the application of robots in different industrial sectors such as nuclear power generation, construction, automobile, firefighting and medicine, etc. is increasing day by day. In large industrial plants generally humans and robots work together to accomplish several tasks and lead to the problem of safety and reliability because any malfunction event of robots may cause human injury or even death. To access the reliability of a robot, sufficient amount of failure data is required which is sometimes very difficult to collect due to rare events of any robot failures. Also, different types of their failure pattern increase the difficulty which finally leads to the problem of uncertainty. To overcome these difficulties, this paper presents a case study by assessing fuzzy fault tree analysis (FFTA) to control robot-related accidents to provide safe working environment to human beings in any industrial plant.

Presented FFTA method uses different fuzzy membership functions to quantify different uncertainty factors and applies alpha-cut coupled weakest t-norm (Tω) based approximate fuzzy arithmetic operations to obtain fuzzy failure probability of robot-human interaction fault event which is the main contribution of the paper.

The result obtained from presented FFTA method is compared with other listing approaches. Critical basic events are also ranked using V-index for making suitable action plan to control robot-related accidents. Study indicates that the presented FFTA is a good alternative method to analyze fault in robot-human interaction for providing safe working environment in an industrial plant.

Existing fuzzy reliability assessment techniques designed for robots mainly use triangular fuzzy numbers (TFNs), triangle vague sets (TVS) or triangle intuitionistic fuzzy sets (IFS) to quantify data uncertainty. Present study overcomes this shortcoming and generalizes the idea of fuzzy reliability assessment for robots by adopting different IFS to control robot-related accidents to provide safe working environment to human. This is the main contribution of the paper.

The purpose of this paper is to show how continual enhancement of knowledge management systems (KMSs) enhances knowledge sharing intention.

This study integrates information system (IS) success with social cognitive theory (SCT) to explain knowledge sharing intention. Based on a survey of 276 KMS users in Taiwan’s information technology industry, the structural equation model has been applied to examine the influence process from a user satisfactory context to personal cognitive beliefs, and thus knowledge sharing intention.

The results indicate that the user satisfactory context stimulated by continual KMS enhancement increases knowledge sharing intention through the mediation of personal cognition of self-efficacy and outcome expectancy.

The results have empirical implications for learning how to motivate developers’ patience and passion for follow-up improvements to meet user expectations empathically, which has been emphasized for service provision.

The originality of this research is its explanation of system adoption behavior, which combines the core of IS success with SCT, links user satisfaction to intention to use, and concerns behavior within a specific context.

Laser powder bed fusion (LPBF) provides the means to produce unique components with almost no restriction on geometry in an extremely short time. However, the high-temperature gradient and high cooling rate produced during the fabrication process result in residual stress, which may prompt part warpage, cracks or even baseplate separation. Accordingly, an appropriate selection of the LPBF processing parameters is essential to ensure the quality of the built part. This study, thus, aims to develop an integrated simulation framework consisting of a single-track heat transfer model and a modified inherent shrinkage method model for predicting the curvature of an Inconel 718 cantilever beam produced using the LPBF process.

The simulation results for the curvature of the cantilever beam are calibrated via a comparison with the experimental observations. It is shown that the calibration factor required to drive the simulation results toward the experimental measurements has the same value for all settings of the laser power and scanning speed. Representative combinations of the laser power and scanning speed are, thus, chosen using the circle packing design method and supplied as inputs to the validated simulation framework to predict the corresponding cantilever beam curvature and density. The simulation results are then used to train artificial neural network models to predict the curvature and solid cooling rate of the cantilever beam for any combination of the laser power and scanning speed within the input design space. The resulting processing maps are screened in accordance with three quality criteria, namely, the part density, the radius of curvature and the solid cooling rate, to determine the optimal processing parameters for the LPBF process.

It is shown that the parameters lying within the optimal region of the processing map reduce the curvature of the cantilever beam by 17.9% and improve the density by as much as 99.97%.

The present study proposes a computational framework, which could find the parameters that not only yield the lowest distortion but also produce fully dense components in the LPBF process.

Polyetheretherketone (PEEK) is used to manufacture biomedical implants because it has a high strength-to-weight ratio and high strength and is biocompatible. However, the use of fused deposition modeling to print a PEEK results in low strength and crystallinity. This study aims to use the Taguchi method to optimize the printing factors to obtain the highest tensile strength of the printed PEEK object. The annealing effect on printed PEEK object and crystallinity are also investigated.

This study determines the printing factors including the printing speed, layer thickness, printing temperature and extrusion width. Taguchi experimental design with a L9 orthogonal array is used to print the tensile specimen and carried out the tensile test to compare the tensile strength and porosity. Analysis of variance (ANOVA) is used to determine the experimental error and to determine the optimization printing parameters to obtain the highest tensile strength. A multivariate linear regression analysis is used to obtain the linear regression equation for predicting the theoretical tensile strength. An X-ray analysis is achieved to evaluate the crystalline of printed object. The effect of annealing is investigated to improve the tensile strength of printed part. An intervertebral lumber device is printed to demonstrate the feasibility of the obtained optimization parameters for practical application.

Taguchi experiment designs nine sets of parameters to print the PEEK tensile specimen. The experimental results and the ANOVA present that the order in which the factors affect the tensile strength for printed PEEK parts is the layer thickness, the extrusion width, the printing speed and the printing temperature. The optimized printing parameters are a printing speed of 5 mm/s, a layer thickness of 0.1 mm, a printing temperature of 395 °C and an extrusion strand width of 0.44 mm. The average tensile strength of printed specimen with the optimized printing parameters is 91.48 MPa, which is slightly less than the theoretical predicted value of 94.34 MPa. After annealing, the tensile strength increases to 98.85 MPa, which is comparable to that for molded PEEK and the porosity decreases to 0.3 from 3.9%. X-ray diffraction results show that all printed and annealed specimens have a high degree of crystallinity. The printed intervertebral lumber device has ultimate compressive load of 13.42 kN.

The optimized printing parameters is suitable for low-price fused deposition modeling machine because it does not involve a table at high temperature and can print the PEEK object with high tensile strength and good crystalline. Annealing parameters offer a good solution for tensile strength improvement.

This study aims to analyze the herding behavior in Southeast Asian stock markets. A cross-sectional absolute deviation of the returns approach is used to identify the presence of herding. Individual stocks and market returns were employed on each stock market on a daily basis during the period of January 2008 to December 2014 from five countries selected to obtain the necessary data. The samples observed consisted of stocks having higher liquidity and larger market capitalization for each stock market. The results suggest that there is significant evidence of herding behavior found in Kuala Lumpur and Philippines Stock Exchanges. In addition, there is no evidence of herding behavior in Indonesia, Singapore, and Thailand Stock Exchanges.

This study investigates to what extent the values perceived by tourists throughout cultural tours impact their overall satisfaction levels and behavioral intentions related to the destination. This study further examines the moderating role of tour guide competency in the relationship patterns concerned.

Empirical data were collected via a survey from 420 foreign tourists who visited Cappadocia and participated in guided cultural tours. Partial least squares-structural equation modeling was used for data analysis.

Study results reveal that the effects of quality, emotional, monetary and social value perceptions of tourists gained through cultural tour experiences on their overall satisfaction levels and the effects of overall satisfaction on recommendation and revisit intention are positive and significant. Furthermore, the moderating role of tour guide competency is significant and positive in the relationships between quality value and satisfaction and between satisfaction and revisit intention.

This study offers a critical analysis of discoveries concerning the pivotal role of tour guide competency within the cultural tour experience.

The purpose of this study aims to understand if there are any differences in the influence of aesthetic experience and creative self-efficacy on innovative behaviors of Thai students and Chinese international students and whether creative self-efficacy has a mediating effect between aesthetic experience and innovative behavior.

Three Thai universities with Chinese international students were selected through purposive sampling. There were 329 valid responses, consisting of responses from 170 Thai students and 159 Chinese students. The data were analyzed by employing multigroup structural equation modeling.

The analysis of the differences between the students of the two countries shows that the influence of aesthetic experience on creative self-efficacy, as well as the creative self-efficacy on innovative behavior of Chinese international students, is greater than that of Thai students, while the influence of aesthetic experience on innovative behavior of Thai students is greater than that of Chinese international students.

There are some differences between Thai and Chinese students, which could be attributed to their differing environments, cultures and prior learning experiences.

The purpose of this paper is to review “institutional experimentation” for protecting workers in response to the contraction of the standard employment relationship and the corresponding rise of “non-standard” forms of paid work.

The paper draws on the existing research and knowledge base of the authors as well as a thorough review of the extant literature relating to: non-standard employment contracts; sources of labour supply engaging in non-standard work; exogenous pressures on the employment relationship; intermediaries that separate the management from the control of labour; and entities that subvert the employment relationship.

Post-war industrial relations scholars characterised the traditional regulatory model of collective bargaining and the standard employment contract as a “web of rules”. As work relations have become more market mediated, new institutional arrangements have developed to govern these relations and regulate the terms of engagement. The paper argues that these are indicative of an emergent “patchwork of rules” which are instructive for scholars, policymakers, workers’ representatives and employers seeking solutions to the contraction of the traditional regulatory model.

While the review of the institutional experimentation is potentially instructive for developing solutions to gaps in labour regulation, a drawback of this approach is that there are limits to the realisation of policy transfer. Some of the initiatives discussed in the paper may be more effective than others for protecting workers on non-standard contracts, but further research is necessary to test their effectiveness including in different contexts.

The findings indicate that a task ahead for the representatives of government, labour and business is to determine how to adapt the emergent patchwork of rules to protect workers from the new vulnerabilities created by, for example, employer extraction and exploitation of their individual bio data, social media data and, not far off, their personal genome sequence.

The paper addresses calls to examine the “institutional intersections” that have informed the changing ways that work is conducted and regulated. These intersections transcend international, national, sectoral and local units of analysis, as well as supply chains, fissured organisational dynamics, intermediaries and online platforms. The analysis also encompasses the broad range of stakeholders including businesses, labour and community groups, nongovernmental organisations and online communities that have influenced changing institutional approaches to employment protection.