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The purpose of this paper is to answer the question that what the best shape of fuzzy sets is in fuzzy systems for function approximation which is essential in many applications of fuzzy systems.

The uniform approximation rates indicate the approximating capabilities of fuzzy systems for function approximation. By Fourier analysis, the uniform approximation rates are estimated for the fuzzy systems with various shapes of if‐part fuzzy sets in the case of single‐input and single‐output. Based on the approximation rates, the relationships between the approximating capabilities and the shapes of fuzzy sets are developed and compared.

The since functions as the input membership functions in fuzzy systems are proved to have the almost best approximation property in a particular class of membership functions.

From the viewpoint of function approximation, the input membership functions are not necessarily positive in fuzzy systems.

For engineers, the sinc‐shaped membership function is a good choice to improve their fuzzy systems in real applications.

The uniform approximation rates of fuzzy systems for function approximation are estimated. Mathematically, the relationships between the approximating capabilities and the shapes of fuzzy sets are analyzed for fuzzy systems.

The purpose of this paper is to research integrating web text resources and mine its emergence.

With the understanding of characteristics of internet resources, this paper will focus on solving the problem of text resource aggregation in open environment and its emergence showed during aggregation over time. The authors process these text resources, both in space and time dimension, through viewing them as an event stream evolving over time, and attempt to discover the evolutionary event patterns and furthermore, to mine the emergence of text content.

The proposed methods are generally applicable to text stream data and have many potential applications in text resource aggregation in open environment.

The main limitation is availability of data.

The paper presents a very useful method for text resource aggregation in an open environment.

The paper presents a new method to integrate web text resources and mine its emergence.

The purpose of this study is to provide an alternative approach to teacher learning on top of the usual practices of listening to experts' lectures and conducting school-based activities among peers in China. A boundary-crossing lesson study (BCLS) through school-university partnership served as an example to illustrate how a class teacher's mindset changed towards her students in equal interactions with university scholars.

With the lenses of action science theory and boundary-crossing learning theory, the study used qualitative research approach to collect and analyze data. One Chinese primary school class teacher from a workshop on narrative action research was selected as the case for this study. Interviewing, observation and document analysis were used to collect data. Data analysis methods included categorization and contextualization of the teacher's mindset change towards her student.

The case teacher, Mrs. Li, collaborated closely in paired teaching with her university partner AP Yu in all the four phases of their BCLS. Each phase was marked with an interactive event such as dialogic illumination, reflexive theorization, embodied conversation, and fusion of teacher and trainer roles. With inspirational trust as a major interactive mechanism, Mrs. Li jumped out of her single-loop learning (changing strategies according to results) to double-loop learning (changing both strategies and values/values). As a result, her mindset changed from attribution to appreciation towards her low-achieving student.

This study made contributions in two ways. First, it examined a class teacher's mindset change towards her student, rather than that of subject matter teachers towards their teaching materials and methods. Second, it revealed how reflective interactions in a special kind of BCLS by school teachers and university scholars may promote the teacher's mindset change. The findings further confirm that having differences as boundaries is not enough for teacher learning. For deep learning like Mrs. Li's mindset change, it requires a respectful and inspirational relationship between school teachers and university scholars in the BCLS.

The purpose of this paper is to investigate the interfacial conductivity and corrosion resistance of the Ni–P/Ti₄O₇ composite coating that is deposited on a carbon steel substrate as bipolar plates for proton exchange membrane fuel cells.

The Ni–P/Ti₄O₇ coating was prepared by electroless plating. Scanning electron microscopy, white light interference, energy dispersive spectrometry and X-ray diffraction were used, respectively, to study the surface morphology, chemical composition and phase composition of coated samples. Electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization were used to test the electrochemical performance and corrosion behavior. The interfacial contact resistance (ICR) was measured via the standard method.

The surface of the Ni–P/Ti₄O₇ coating is complete and dense and without obvious defects. The electrochemical test results show that the Ni–P/Ti₄O₇ coating provides better corrosion resistance than the Ni–P coating and substrate. Compared with the Ni–P coating, the ICR of the Ni–P/Ti₄O₇ coating is lower by about 82.7%. This is because the coating has more conductive contact points. The more exciting thing is that the ICR of the Ni–P/Ti₄O₇ coating only increases to 12.38 mΩ·cm² after 5 h of polarization.

This paper provides a method for achieving surface modification of metal bipolar plates. Introducing Ti₄O₇ particles in the Ni–P layer reduces the contact resistance before and after polarization while ensuring good corrosion resistance.

The purpose of this paper is to develop a potential nanoparticles lubricant additive for solving the problem of the insolubility and stable dispersity; the complex nanoparticles with core-shell structures are less studied in the field. Therefore, this paper determines novel complex nanoparticles and their tribological properties.

According to the conventional preparation method, the complex nanoparticle styrene/calcium borate (PS/O-CaB) was synthesized. The microstructures of the as-obtained samples were characterized by X-ray diffraction infrared spectroscopy and thermogravimetric analysis. Tribological properties of PS/O-CaB used as lubricating oil additive were evaluated on four-ball tribometer. The worn surface of the steel ball was investigated by a three-dimensional non-contact surface profilometer and X-ray photoelectron spectroscopy (XPS).

The results of the structure characteristic indicate two different crystalline forms, namely, Ca₂B₆O₁₁ and Ca₂B₂O₅, and the average size of calcium borate nanoparticles in PS/O-CaB is about 20-40 nm. Moreover, the good tribological properties are due to a wear resistance film containing both depositions and the tribochemical reaction products which comprise B2O3, FeB and Fe2O3.

Novel complex nanoparticles with core-shell structure (PS/O-CaB) were successfully prepared. Moreover, the PS/O-CaB shows excellent tribological capacity such as load-carrying, friction-reducing and antiwear property.