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The purpose of this study is to investigate the characteristic and function of oxide film formed on grinding wheel in electrolytic in-process dressing (ELID) precision grinding and improve the quality of ELID grinding.

Dynamic film forming experiments were carried out with a simulation device close to the actual processing conditions. Then, the ELID grinding experiments of bearing rings were performed using grinding wheels with good film forming effect. The experiment was designed by quadratic regression general rotation combination method. The influence of grinding depth, electrolytic voltage, duty cycle and grinding wheel linear speed on grinding effect is analyzed.

A mathematical model for the formation rate of oxide film was established. The experiments show that the composition of grinding wheel and grinding fluid, as well as the electrical parameters, influence the film forming effect. Thus, the oxide film plays an important role in ELID grinding.

This study provides a reference for the design and selection of grinding wheel and grinding fluid and the setting of process parameters in ELID grinding.

The number of farms engaged in grain production in China has been declining in recent years. Limited efforts have been devoted to examine why producers quit from grain production and how such exits affect China's grain output. Such information, however, is invaluable in understanding whether the exit from grain production should be encouraged and if so, how. The purpose of this paper is to identify the factors that influence farmers' decision to quit from grain production, with a view to drawing implications for devising policies to deal with such exits.

Both descriptive statistics and econometric techniques are used to analyse a set of unique and comprehensive farm‐level survey data to identify key factors that affect farmers' decision to quit from grain production.

Key factors that influence a farm to quit from, or stay in, grain production include: family size, the share of farming labour out of total family labour, per capita arable land, the proportion of land used for grain production, the share of family income from grains. It was also found that the level of grain prices and the sunk cost in farming, chiefly in grain production, also affect the likelihood that a household will stay or exit from grain production. Further, farmers in more economically developed regions are more likely to quit from grain production.

The paper's findings clearly indicate that farms with a larger scale of grain production and earning higher income from grain are the major contributors to China's grain production. Potential exists for China to raise its total grain output if the land from those exiting farmers is readily made available to larger producers, enabling them to further benefit from the economies of scale.

Examining the influence of ethnic food tourists' perception of hygiene on their attitudinal loyalty formation is the purpose of this study. Specifically, How to demonstrate touristsʼ perception of ethnic food hygiene is the key question, and moreover, the study also investigates whether and how the stages of attitudinal loyalty in this study, which are perceived authenticity, positive emotion, and perceived value, are illustrated in this mechanism and are affected by tourist perceptions of hygiene?

By engaging in the critical debate around the topic of hygiene perception, this study explores the influence of this factor on tourist's attitudinal loyalty, including the cognitive, affective and conative aspects, to ethnic food through the adoption of perceived authenticity, positive emotion and perceived value. A survey was conducted at the Xijiang Miao Village, a very popular ethnic tourism destination in China.

This study reveals that ethnic food tourists' perceptions of hygiene have five dimensions. One of these plays a direct predictor role in developing effective conative loyalty (perceived value). Tourists' perceptions of authenticity and positive emotion representing cognitive and affective loyalty are confirmed in their direct effect on conative loyalty as well. The five dimensions of perceptions of hygiene identified have varying degrees of influence on the three stages of attitudinal loyalty.

The unique contribution of this study lies in two points: (1) it has discovered the way that tourists' perceptions of the hygienic preparation of ethnic food in the ethnic destination is constructed, and (2) it investigated the relationship between tourists' perceptions of hygiene and the three stages of attitudinal loyalty.

Traditional nondestructive failure localization techniques are increasingly difficult to meet the requirements of high density and integration of system in package (SIP) devices in terms of resolution and accuracy. Time domain reflection (TDR) is recognized as a novel positioning analysis technology gradually being used in the electronics industry because of the good compatibility, high accuracy and high efficiency. However, there are limited reports focus on the application of TDR technology to SiP devices.

In this study, the authors used the TDR technique to locate the failure of SiP devices, and the results showed that the TDR technique can accurately locate the cracking of internal solder joints of SiP devices.

The measured transmission rate of electromagnetic wave signal was 9.56 × 107 m/s in the experimental SiP devices. In addition, the TDR technique successfully located the failure point, which was mainly caused by the cracking of the solder joint at the edge of the SiP device after 1,500 thermal cycles.

TDR technology is creatively applied to SiP device failure location, and quantitative analysis is realized.

Night lighting reflects the prosperous development of economic and the increasingly rich and colorful cultural life. Currently, various technical standards, protocols and management specifications have been developed to build a safe, comfortable and economical lighting environment. However, prevailing evaluation systems focus on objective indexes of illumination and have ignored environmental characteristics and subjective feelings and lacked consideration of regional culture, economic benefit, management and maintenance. In this context, a lighting evaluation system combining subjective and objective is proposed for the first time in this study to explore approaches to guide the development of a healthy and comfortable urban night-time environment.

Existing research and relevant lighting standards are analyzed and an evaluation model with a logical hierarchy is constructed by combining with the evaluation theory that is set based on people and the environment. The index weights were scientifically determined on the basis of the analytic hierarchy process (AHP) and fuzzy comprehensive evaluation method. The rationality and validity of the proposed evaluation system is verified in accordance with field projects and case studies.

Taking into account traditional and cultural factors, the evaluation model established has an acceptable accuracy. Evaluation based on subjective-objective combination can provide a scientific basis for the management and optimization of night lighting.

The proposed evaluation system can serve as a guiding reference for other areas of cultural identity and esthetic perspective.

The purpose of this paper is to introduce a co‐simulation method to study the ground maneuvers of aircraft anti‐skid braking and steering.

A virtual prototype of aircraft is established in the multibody system dynamics software MSC.ADAMS/Aircraft. The anti‐skid braking control model, which adopts the multi‐threshold PID control method with a slip‐velocity‐controlled, pressure‐bias‐modulated (PBM) system, is established in MATLAB/Simulink. EASY5 is used to establish the hydraulic system of nose wheel steering. The ADAMS model is connected to block diagrams of the anti‐skid braking control model in MATLAB/Simulink, and is also connected to the block diagrams of nose wheel steering system model in EASY5, so that the ground maneuvers of aircraft anti‐skid braking and steering are simulated separately.

Results are presented to investigate the performance of anti‐skid braking system in aircraft anti‐skid simulation. In aircraft steering simulation, the influence of two important parameters on the forces acting on the tires is discussed in detail, and the safe area to prevent aircraft sideslip is obtained.

This paper presents an advanced method to study the ground maneuvers of aircraft anti‐skid braking and steering, and establishes an integrated aircraft model of airframe, landing gear, steering system, and anti‐skid braking system to investigate the interaction of each subsystem via simulation.

Nowadays, proactive P2P worm (PRWORM) poses a latent threat to internet infrastructure and common users for the fatal vulnerabilities in homogeneous P2P software. It is more difficult to contain PRWORM because of its fast spread speed. Current techniques are not adequate to quarantine PRWORM, mainly because of their inaccuracy and slow response to attacks. The purpose of this paper is to propose an accurate and real‐time approach for PRWORM containment.

First, the authors present a new methodology to contain PRWORM via proper authentication of initiators of P2P communications. Second, three simple network protocols are proposed to fulfill automatic authentication.

Both simulations and strictly mathematical proof by Strand Space Model represent that the authors' work is able to accurately quarantine PRWORM in real time. Furthermore, proof shows the three network protocols are resistant to popular attacks such as man‐in‐the‐middle attack and replay attack.

First, the authors propose an authentication based method to contain proactive P2P worm and second, use strand space model to proof the effectiveness and security of the method.

The purpose of this paper is to explore the relationship among the air quality index (AQI) of Beijing-Tianjin-Shijiazhuang region and find countermeasures to control the pollution situation.

This study used the grey convex relation model to calculate the grey correlation degree through the AQI of Beijing-Tianjin-Shijiazhuang region.

By analyzing the calculation results among the three cities, it was concluded that the air quality of the three cities is closely related. Therefore, the Beijing-Tianjin-Shijiazhuang region should collaboratively improve the air quality for common development.

More approaches may be adopted to calculate the grey correlation degree in the further research studies.

There exist some practical difficulties in implementing these governance measures.

The paper gives the countermeasures to control the pollution situation in Beijing-Tianjin-Shijiazhuang region.

The purpose of this paper is to predict the main economic indices of online shopping in China.

A fractional order weakening buffer operator (WBO) for the GM(1,1) model is put forward in order to solve the problem of limited nonlinear data. The order number of WBO can adjust in line with the scenario.

The experimental results indicate that the proposed method can consider the scenario and obtain more accurate forecasting results.

This study found that the slowdown of growth trend after the previous high speed expansion period will continue, and the online shopping sellers should make more efforts to develop potential consumers to increase its turnover.