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The study aims to pioneer an innovative approach for the evaluation of government portal websites (GPWs) by introducing an eye-tracking-based method. The research meticulously pinpoints and analyses the distinct usability issues and challenges that users encounter while navigating and interacting with GPWs.

This study devises an eye-tracking-based GPW usability evaluation approach, which focuses on the major functions (i.e. government information disclosure, government services and interactive responses) of GPWs. An Entropy Weighted Technique for Order Preference by Similarity to an Ideal Solution (EW-TOPSIS) method is employed to process eye-tracking indicator results for deriving GPW usability results.

The proposed approach is demonstrated to assess the usability of 12 GPWs in pilot smart cities in China, and it is found that most GPWs have lower-than-average usability. GPWs with low usability require more cognitive load that exhibit increased fixation and saccade. The comparisons among the GPW usability results from (1) the eye-tracking experiment, (2) questionnaire surveys and (3) the ready-made performance evaluation report validate the effectiveness of eye-tracking-based GPW usability evaluation.

The work contributes to shifting the GPW usability evaluation approach from a subjective judgment paradigm to an objective paradigm, as well as provides implications for enhancing GPW usability, including improving search function, reducing website complexity and prioritizing user needs.

To propose a new investment-income valuation model by real options approach (ROA) for old community renewal (OCR) projects, which could help the government attract private capital's participation.

The new model is proposed by identifying the types of options private capital has in the OCR project, selecting the option model most suitable for private capital investment decisions, improving the valuation model through the triangular fuzzy numbers to take into account the uncertainty and flexibility, and demonstrating the feasibility of the calculation model through an actual OCR project case.

The new model can valuate OCR projects more accurately based on considering uncertainty and flexibility, compared with conventional methods that often underestimate the value of OCR projects.

The investment-income of OCR projects shall be re-valuated from the lens of real options, which could help reveal more real benefits beyond the capital growth of OCR projects, enable the government to attract private capital's investment in OCR, and alleviate government fiscal pressure.

The proposed OCR-oriented investment-income valuation model systematically analyzes the applicability of real option value (ROV) to OCR projects, innovatively integrates the ROV and the net present value (NPV) as expanded net present value (ENPV), and accurately evaluate real benefits in comparison with existing models. Furthermore, the newly proposed model holds the potential to be transferred to various social welfare projects as a tool to attract private capital's participation.

To study the influence of storage time and environment on the solderability of electroless nickel plated samples with Sn‐3.8Ag‐0.7Cu and Sn‐3.5Ag lead‐free solders and to provide criteria for the use of an electroless nickel (Ni‐P) under bump metallization (UBM) without immersion gold protection.

Electroless nickel coatings were deposited onto pure aluminium foil through a procedure developed for the UBM of wafers prior to flip chip bumping. Their solderability with lead‐free solders was studied using the wetting balance technique. Samples stored in different environments for different periods of time were tested to study the dependence of the solderability of Ni‐P coatings on the storage time and temperature. The degree of oxidation of the Ni‐P coatings was examined by means of X‐ray photoelectron spectroscopy and the surface microstructure and roughness of the coatings were analyzed by scanning electron microscopy and atomic force microscopy.

It was found that the Ni‐P coatings were unacceptable for direct soldering without the assistance of a flux, due to poor wettability, even when using a freshly prepared Ni‐P coating. Therefore, a suitable flux with nitrogen inerting had to be applied to assist the soldering process. The results also show that the solderability of Ni‐P coatings was affected by the phosphorus content, and the Ni‐P coating with high phosphorus content had a good solderability. The storage time and temperature did not influence the wettability significantly with the assistance of strong flux.

The stability of the plating solution and the consistence of the phosphorus content in the coating are not easily controlled. This has resulted in implications for surface analysis and wetting testing. Ni‐P coatings with different levels of phosphorus content are being investigated in detail.

The value of the paper lies in its study on the solderability of lead‐free solders to Ni‐P coating after storage in different environments and for different periods, which can provide some criteria for the use of Ni‐P UBM without immersion gold protection.

The study aims to find potential method to enhance the stability and antioxidant activity of vitamins.

Vitamin E (VE) and β-cyclodextrin (CD) were used to prepare the VE-β-CD inclusion complex via a solution method. The yielded VE-β-CD obtained from optimal experimental conditions was characterized. The mechanism of complex formation and the properties of the complex was investigated by steady-state and time-resolved fluorescence techniques. The antioxidant activity of VE-β-CD was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and compared with pure VE.

Three experimental factors – reaction temperature (T), molar ratio of VE to β-CD (rm) and inclusion time (t) – were studied for the preparation of VE-β-CD. At experimental conditions of T = 60°C, rm = 1:3 and t = 3 h, a maximum inclusion rate of VE (78.62%) was obtained. The Fourier-transform infrared spectroscopy (FTIR) shows that VE molecule was physically encapsulated by β-CD in the yielded product. Subsequentially, the steady-state fluorescence intensity of VE was found to increase upon encapsulation by β-CD due to the hindrance of fluorescence quenching of VE molecules inside the hydrophobic cavity of β-CD, and an inclusion constant K was determined to equal 3.58 × 103 L/mol from the fluorescence results. The fluorescent observation was confirmed by time-resolved fluorescence experiment as the lifetime of VE increased with an increase in β-CD concentration.

The ability of removing radicals by VE was significantly enhanced after the formation of inclusion complex with β-CD.

This study aims to evaluate the rheological properties of aviation lubricating oil under conditions of heavy load, high speed and high temperature and the applicability of the classical rheological model under severe conditions.

A Chinese aviation lubricating oil was used and its traction curves were obtained using a new two-disk tribotester. Its rheological parameters were calculated based on empirical formulae. Moreover, the traction force was calculated based on the classical Eyring rheological model.

The traction curves are obtained with respect to contact pressure, temperature and rolling speed. The rheological parameters are significantly influenced by environmental factors, especially viscosity. The traction force calculated using the Eyring model is consistent with the experimental results.

A novel two-disk tribotester was designed using a gas bearing and speed–force closed-loop control to ensure measurement accuracy. The mechanism of rheological properties was analyzed and the applicability of the classical rheological model under severe conditions was verified. It provided an experimental and theoretical basis for expanding the application of classical rheological models under extreme conditions.

This paper aims to analyze the bearing characteristics of the high speed train window glass under aerodynamic load effects.

In order to obtain the dynamic strain response of passenger compartment window glass during high-speed train crossing the tunnel, taking the passenger compartment window glass of the CRH3 high speed train on Wuhan–Guangzhou High Speed Railway as the research object, this study tests the strain dynamic response and maximum principal stress of the high speed train passing through the tunnel entrance and exit, the tunnel and tunnel groups as well as trains meeting in the tunnel at an average speed of 300 km·h-1.

The results show that while crossing the tunnel, the passenger compartment window glass of high speed train is subjected to the alternating action of positive and negative air pressures, which shows the typical mechanic characteristics of the alternating fatigue stress of positive-negative transient strain. The maximum principal stress of passenger compartment window glass for high speed train caused by tunnel aerodynamic effects does not exceed 5 MPa, and the maximum value occurs at the corresponding time of crossing the tunnel groups. The high speed train window glass bears medium and low strain rates under the action of tunnel aerodynamic effects, while the maximum strain rate occurs at the meeting moment when the window glass meets the train head approaching from the opposite side in the tunnel. The shear modulus of laminated glass PVB film that makes up high speed train window glass is sensitive to the temperature and action time. The dynamically equivalent thickness and stiffness of the laminated glass and the dynamic bearing capacity of the window glass decrease with the increase of the action time under tunnel aerodynamic pressure. Thus, the influence of the loading action time and fatigue under tunnel aerodynamic effects on the glass strength should be considered in the design for the bearing performance of high speed train window glass.

The research results provide data support for the analysis of mechanical characteristics, damage mechanism, strength design and structural optimization of high speed train glass.

Although there have been many discussions on the status and development of original equipment manufacturers (OEMs), theory on how they survive is minimal. Little is known about how OEMs survive and upgrade to other business models, such as original design manufacturers (ODMs) and original brand manufacturers (OBMs), in emerging economies. The purpose of this paper is to extend the theory on the survival path of OEMs from the perspective of emerging countries by examining how OEMs survive cost pressures and upgrade to ODMs or OBMs.

Using a multi-case study method, this study analyzes the survival path employed by OEMs by examining eight firms in the Chinese toy industry.

This study shows that OEMs remain weak in the global toy industry chain due to labor costs. While some OEMs move to low-cost regions, others turn to OBM management, after transitioning through an ODM model, by investing in research and development and marketing.

This study explores the survival paths of OEM enterprises, showing that OEMs can first upgrade to ODMs and then to OBMs, or they can directly upgrade to OBMs. Shifting from OEM to ODM is an important step in the transition process, although the contract that OEMs have with their foreign partners does not change significantly.

The purpose of this paper is to solve the reactive power adjustment and the overvoltage suppression problems in the extra high voltage (EHV) long distance grid, which often appears transient overvoltage, light load loss and other issues.

One 800 kV EHV magnetically saturation controllable reactor (MSCR) used self-power supply control system is designed. The structure and the working mechanism of the novel MSCR are analyzed in detail. Then the control and capacity step adjustment characteristics are obtained by experiments. The harmonic characteristic is studied by theoretical analysis and low voltage test.

To solve the problem of harmonics in the working current of nets windings, the fifth and the seventh filers are equipped between the compensation windings and the control system. The effectiveness of the harmonic suppression method is proved by simulation and experiments.

It proves that the 800 kV EHV MSCR design in this paper can achieve the purpose of the reactive power continuous linear adjustment, and the capacity adjustment is sensitive. After filtering, the harmonics level of the working current meets the standard of the EHV grid.

This paper aims to prepare a composite film on LY12 aluminum (Al) alloy by immersing in dodecyl phosphate and cerium nitrate solution by self-assembling methods. The effect of dipping sequence in dodecyl phosphate and cerium nitrate solution on the corrosion resistance of the composite film is studied.

The corrosion resistance of the dodecyl phosphate/cerium composite film is investigated by electrochemical measurement and film composition analysis.

The dipping sequence in dodecyl phosphate and cerium nitrate solutions has a significant impact on the corrosion resistance of the composite film. It shows best corrosion resistance by first dipping in dodecyl phosphate and then dipping in cerium nitrate solution.

The research shown in this work lays a scientific basis of the film preparation for industrial applications in the future.

The purpose of this work is to design the wire beam electrode (WBE) of P110 steel and study its corrosion behavior and mechanism under high temperature and pressure.

Packaging materials of the new type P110 steel WBE and high pressure stable WBE structure were designed. A metallurgical microscope (XJP-3C) and scanning electron microscopy (EV0 MA15 Zeiss) with an energy dispersive spectrometer were used to analyze the microstructure and composition of the P110 steel. The electrochemical workstation (CS310, CorrTest Instrument Co., Ltd) with a WBE potential and current scanner was used to analyze the corrosion mechanism of P110 steel.

According to the analysis of Nyquist plots at different temperatures, the corrosion resistance of P110 steel decreases with the increase of temperature under atmospheric pressure. In addition, R_p of P110 steel under high pressure is maintained in the range of 200 ∼ 375 Ωcm², while that under atmospheric pressure is maintained in the range of 20 ∼ 160 Ωcm², indicating that the corrosion products on P110 steel under high pressure is denser, which improves the corrosion resistance of P110 steel to a certain extent.

The WBE applied in high temperature and pressure environment is in blank. This work designed and prepared a WBE of P110 steel for high temperature and pressure environment, and the corrosion mechanism of P110 steel was revealed by using the designed WBE.