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The purpose of this paper is to relate to the real-time navigation and tracking of pedestrians in a closed environment. To restrain accumulated error of low-cost microelectromechanical system inertial navigation system and adapt to the real-time navigation of pedestrians at different speeds, the authors proposed an improved inertial navigation system (INS)/pedestrian dead reckoning (PDR)/ultra wideband (UWB) integrated positioning method for indoor foot-mounted pedestrians.

This paper proposes a self-adaptive integrated positioning algorithm that can recognize multi-gait and realize a high accurate pedestrian multi-gait indoor positioning. First, the corresponding gait method is used to detect different gaits of pedestrians at different velocities; second, the INS/PDR/UWB integrated system is used to get the positioning information. Thus, the INS/UWB integrated system is used when the pedestrian moves at normal speed; the PDR/UWB integrated system is used when the pedestrian moves at rapid speed. Finally, the adaptive Kalman filter correction method is adopted to modify system errors and improve the positioning performance of integrated system.

The algorithm presented in this paper improves performance of indoor pedestrian integrated positioning system from three aspects: in the view of different pedestrian gaits at different speeds, the zero velocity detection and stride frequency detection are adopted on the integrated positioning system. Further, the accuracy of inertial positioning systems can be improved; the attitude fusion filter is used to obtain the optimal quaternion and improve the accuracy of INS positioning system and PDR positioning system; because of the errors of adaptive integrated positioning system, the adaptive filter is proposed to correct errors and improve integrated positioning accuracy and stability. The adaptive filtering algorithm can effectively restrain the divergence problem caused by outliers. Compared to the KF algorithm, AKF algorithm can better improve the fault tolerance and precision of integrated positioning system.

The INS/PDR/UWB integrated system is built to track pedestrian position and attitude. Finally, an adaptive Kalman filter is used to improve the accuracy and stability of integrated positioning system.

This paper aims to present performance comparison of fiber sheet-strengthened reinforced concrete (RC) beams bonded with geopolymer and epoxy resin under ambient and fire conditions.

This study presents experimental results of bending tests at ambient temperature and fire resistance tests on two control beams and eight fiber sheet-strengthened RC beams. The test variables include fiber sheet type (carbon fiber [CF] and basalt fiber [BF] sheet), number of layers of fiber sheet (one and two layers) and adhesive agent type (geopolymers and epoxy resin). Data generated from these tests were used to evaluate and compare the strengthening effectiveness of CF-reinforced polymer (CFRP) and CF-reinforced geopolymer (CFRG) at ambient temperature and under fire exposure conditions.

Test results clearly show that the CFRG system can provide good strengthening effectiveness on RC beams at ambient temperature, as the CFRP system, owing to excellent bond properties of geopolymers. Although geopolymers possess better bonding properties at high temperature than organic matrix, the strengthened beams bonded with geopolymer do not exhibit better fire resistance than that those bonded with epoxy resin, owing to early falling-off of fire insulation. Thus, in CFRG-strengthened beams, relevant measures are to be taken to minimize falling-off of fire insulation to achieve good fire resistance.

The presented results are from unique fire tests and provide valuable insight (and information) on the performance of fiber sheet-strengthened RC beams bonded with geopolymer and epoxy resin under ambient and fire conditions.

The paper aims to introduce the fabrication of a medium steel aircraft part by hybrid deposition and micro-rolling technology (HDMR) and illustrate its advantages, microstructure features and mechanical properties of the part.

The HDMR technology contains two procedures happening almost at the same time: the welding deposition procedure and then the micro-rolling procedure. It takes the gas metal arc welding as the heat source to melt a metal wire and deposit metal in the welding deposition procedure. The metal just deposited is rolled synchronously by a micro roller following the welding torch in micro-rolling procedure almost at the same time layer by layer. The paper presents a contrast of the grain morphology of metal parts produced respectively by HDMR and freedom arc deposition (FAD) and the mechanical properties of metal parts of the same metal from HDMR casting, forging and FAD methods.

HDMR breaks the dendrite grain of welding beads into the fine crisscross grains. The mechanical properties of metal parts are improved distinctly by the micro-rolling procedure compared to casting, forging and FAD.

In addition, the application of HDMR technology has succeeded in the fabrication of an eligible aircraft metal part, which is quite difficult to achieve using other additive manufacturing (AM) or casting technologies.

HDMR has the advantage of equiponderance manufacturing by micro-rolling compared to other AM technologies. The metal part fabricated by HDMR technology obtains the fine crisscross grains and brings hope for AM metal components with excellent mechanical properties for aircraft applications.

The purpose of this paper is to explore the differences between Hong Kong Special Administrative Region (SAR) and Mainland in terms of education and also the influence of it on doing comparative educational research. Hong Kong SAR is ruled by the Chinese Government under the framework of “One country, two systems.” It makes Hong Kong SAR different from other Mainland cities based on different aspects including, education. The finding of this paper provides a systematic review about the differences between these two Chinese societies in terms of education and also implication for conducting comparative educational research in these two societies and also generating some implications for cross-national and cross-cultural study in education.

This paper made references from the framework proposed by Bray and Thomas (1995) in relation to comparative educational research to make comparison between Hong Kong SAR and Mainland China. Multi-level comparison is conducted between two societies in terms of education, especially aspects relating to conducting educational research sat social, school and individual levels.

This paper identified the influence of “One county, two systems” on education at different levels such as ideology, school management system and use of languages in teaching. Such differences affect the choice of topics, sampling strategy, research design, data analysis and interpretation and also ethical considerations when conducting comparative research between Hong Kong SAR and Mainland China.

This paper is an integrated analysis of conducting educational research in two Chinese societies and provides insights for further discussions and possible research about this topic.

The form error of shaft and hole parts is inevitable because of the machining error caused by rotation error of tool axis in machine tools where the elliptical form error is the most common in shaft and bearing bush. The purpose of this paper is to present the relationship between the elliptical form error and rotation accuracy for hydrostatic journal bearing in precision spindle and rotation table.

An error averaging effect model of hydrostatic journal bearing is established by using Reynolds equation, pressure boundary conditions, flux continuity equation of the land and kinetic equation of shaft in hydrostatic journal bearing. The effects of shaft and bearing bush on rotation accuracy were analyzed quantitatively.

The results reveal that the effect of shaft elliptical form error on rotation accuracy was six times larger than bearing bush. Therefore, to improve the rotation accuracy of hydrostatic journal bearing in spindle or rotation table, the machining error of shaft should be controlled carefully.

An error averaging model is proposed to evaluate the effect of an elliptical form error on rotation accuracy of hydrostatic journal bearings, which solves the Reynolds equation, the flux continuity equation and the kinetic equation. The determination of form error parameters of shaft and bearing bush can be yielded from finding results of this study for precision design of hydrostatic journal bearings.

This paper aims to investigate the effect of CaF₂ (calcium fluoride) addition as a solid lubricant on the friction and wear behaviour of sintered Fe-Cu-C materials under different loads.

In this study, the effects of CaF₂ added in varying weight percentages on the friction-wear properties of Fe-2Cu-0.8C alloys are investigated. Five Fe-2Cu-0.8C-based compositions comprising CaF₂ in 0, 3, 6, 9 and 12 Wt.% were prepared using the single-stage compaction and sintering technique. Friction coefficient, wear loss, hardness and compressive strength of the specimens were measured. The worn-out surfaces were analysed using a scanning electron microscope. Friction and wear tests were carried out on pin-on-disc machine under dry sliding conditions at room temperature.

The alloy with 3 Wt.% CaF₂ was found to be useful in improving wear and friction properties, whereas higher contents of CaF₂ resulted in increased wear and friction. Apart from enhanced tribological properties, a slight decrease in the compressive strength was also observed in the 3-Wt.%-CaF₂-added sample. Adhesion and abrasion were the prominent wear types observed during this study.

A new self-lubricating composite is developed where CaF₂ is used as a solid lubricant in a Fe-Cu-C-based matrix. CaF₂, being a high-temperature lubricant, is tried and tested for friction and wear at room temperature, and the results show that the addition of CaF₂ in Fe-Cu-C improved its friction and wear properties. Thus, the developed material can be used for antifriction applications.

The purpose of this study is to conceptualize the business model from a value network perspective and to investigate how top managers' individual characteristics contribute to business model innovation.

On the basis of upper echelons theory and contingency theory, this study empirically examines the micro‐macro link between top managers' human and social capital and firm business model innovation.

Using survey data collected from 146 Chinese firms, the findings indicate that both top managers' managerial and entrepreneurial skills and managerial ties significantly lead to business model innovation. Furthermore, the interaction between entrepreneurial skills and managerial ties enhances, yet the interaction between managerial skills and managerial ties inhibits business model innovation.

By proposing a value network‐based definition for the business model, this study provides additional insights into the current debate on the definition and architecture of business model. Further, the current study contributes to an emerging body of business model research by demonstrating, for the first time, that a manager's individual characteristics can both directly and interactively drive business model innovation in the context of emerging economies.