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Aircraft assembly demands high position accuracy of drilled fastener holes. Automated drilling is a key technology to fulfill the requirement. The purpose of the paper is to conduct positioning variation analysis and control for an automated drilling to achieve a high positioning accuracy.

The nominal and varied connective models of automated drilling are constructed for positioning variation analysis regarding automated drilling. The principle of a strategy for reducing positioning variation in drilling, which shortens the positioning variation chain with the aid of an industrial camera-based vision system, is explored. Moreover, other strategies for positioning variation control are developed based on mathematical analysis to further reduce the position errors of the drilled fastener holes.

The propagation and accumulation of an automated drilling system’s positioning variation are explored. The principle of reducing positioning variation in an automated drilling using a monocular vision system is discussed from the view of variation chain.

The strategies for reducing positioning variation, rooted in the constructed positioning variation models, have been applied to a machine-tool based automated drilling system. The system is developed for a wing assembly of an aircraft in the Aviation Industry Corporation of China.

Propagation, accumulation and control of positioning variation in an automated drilling are comprehensively explored. Based on this, the positioning accuracy in an automated drilling is controlled below 0.13 mm, which can meet the requirement for the assembly of the aircraft.

Assembly variation analysis generally demands probability distributions of variation sources. However, due to small production volume in aircraft manufacturing, especially prototype manufacturing, the probability distributions are hard to obtain, and only the small-sample data of variation sources can be consulted. Thus, this paper aims to propose a variation analysis method driven by small-sample data for compliant aero-structure assembly.

First, a hybrid assembly variation model, integrating rigid effects with flexibility, is constructed based on the homogeneous transformation and elasticity mechanics. Then, the bootstrap approach is introduced to estimate a variation source based on small-sample data. The influences of bootstrap parameters on the estimation accuracy are analyzed to select suitable parameters for acceptable estimation performance. Finally, the process of assembly variation analysis driven by small-sample data is demonstrated.

A variation analysis method driven by small-sample data, considering both rigid effects and flexibility, is proposed for aero-structure assembly. The method provides a good complement to traditional variation analysis methods based on probability distributions of variation sources.

With the proposed method, even if probability distribution information of variation sources cannot be obtained, accurate estimation of the assembly variation could be achieved. The method is well suited for aircraft assembly, especially in the stage of prototype manufacturing.

A variation analysis method driven by small-sample data is proposed for aero-structure assembly, which can be extended to deal with other similar applications.

This paper aims to propose a roadmap to control the robot–subassembly (R–S) coordination errors in movable robotic drilling. Fastener hole drilling for multi-station aircraft assembly demands a robotic drilling system with expanded working volume and high positioning accuracy. However, coordination errors often exist between the robot and the subassembly to be drilled because of disturbances.

Mechanical pre-locating and vision-based robot base frame calibration are consecutively implemented to achieve in-process robot relocation after station transfer. Thus, coordination errors induced by robotic platform movements, inconsistent thermal effects, etc. are eliminated. The two-dimensional (2D) vision system is applied to measure the remainder of the R–S coordination errors, which is used to enhance the positioning accuracy of the robot. Accurate estimation of measured positioning errors is of great significance for evaluating the positioning accuracy. For well estimation of the positioning errors with small samples, a bootstrap approach is put forward.

A roadmap for R–S coordination error control using a 2D vision system, composed of in-process relocation, coordination error measurement and drilled position correction, is developed for the movable robotic drilling.

The proposed roadmap has been integrated into a drilling system for the assembly of flight control surfaces of a transport aircraft in Aviation Industry Corporation of China. The position accuracy of the drilled fastener holes is well ensured.

A complete roadmap for controlling coordination errors and improving positioning accuracy is proposed, which makes the high accuracy and efficiency available in movable robotic drilling for aircraft manufacturing.

A large number of fastener holes have to be drilled with high quality in the circumferential splice region during the assembly of aircraft fuselage. The purpose of this paper is to design an automatic stepping mechanism for a circumferential splice drilling machine, to meet the requirements of large workspace and high accuracy in drilling at the same time.

A docking position detection method based on magnetic proximity sensors is proposed for the positioning of the arc-shaped rail with respect to the circumferential rails, which significantly improves the accuracy and reliability of automatic stepping. The slipping phenomenon of the end-effector is analyzed, and the optimized counter weights are used to eliminate the slipping and improve the working stability of the stepping mechanism.

An automatic stepping mechanism is developed for the circumferential splice drilling machine, which comprises the docking position detection method and the elimination/suppression method of the end-effector’s slipping.

The proposed automatic stepping mechanism has been integrated into the circumferential splice drilling machine for the fuselage assembly in an aircraft company in China.

An automatic stepping scheme for the circumferential splice drilling machine is proposed, which enhances the efficiency in circumferential splice drilling in aircraft fuselage assembly.

This research outlines the Hong Kong film industry with examination of key actors, directors, films, and production companies within the martial arts genre of Hong Kong Action Cinema. Hong Kong Film Award winners and nominees, core films within genres, and core reference works both general and theoretical from experts in the field of Hong Kong martial arts film research have been highlighted. Web sites are suggested that provide reviews of Hong Kong martial arts films, biographical information on a variety of actors and actresses as well as comprehensive bibliographic information on select films. Also included are commercial Web sites that provide Hong Kong martial arts films.

This paper seeks to discuss the genealogical sources for Chinese immigrants as well as the settlement of Chinese in the USA and the historical evolution of Chinese names, their origins, arrangement and development. It aims to cover the origins of various classes of Chinese surnames, followed by the content description of a traditional genealogical book for jiapu.

The paper researches the various ways that a Chinese person can find out about their ancestry.

The paper reveals the roles of libraries, including serving the needs of patrons interested in genealogical research, preserving and interpreting information through oral and family history projects and collaborating with other libraries through interlibrary loan, document delivery, library consortia, collection management and international resource‐sharing.

The study provides information on where and how to locate the genealogical resources for researching the genealogy of a Chinese family.

The paper analyzes the value of genealogical research as a documentary source for population history, life expectancy in a clan, marriages and family connections, as well as lineage organizations and inter‐lineage relations.

This paper aims to chart the breadth and acceleration of organic markets domestic and international and discuss the obstacles and possible ways that confront enterprises who engage in organic exports from and imports to China.

There is much extant research that investigates the organic certification and its market development in the developed world. However, little emphasis is given to China, the highest growing organic market. This research aims to narrow this gap in the literature by reviewing organic certification and the market in China.

China's organic products are mainly exported to developed countries, but the growing affluence of Chinese consumers and expanding foreign expatriate community in China is developing a domestic market for organic food. Organic products are increasingly being imported. Organic standards and certification system in China have been established and under the implementation, with all stages of the organic marketing chain regulated by law and guaranteed. The lack of an equivalent or compliant system forces Chinese organic exports to enter the international market through multi‐certification, and foreign organic imports to the China market possibly through certification by a CNAS‐ACB.

This paper provides a unique insight into a wide range of China organic certification systems and the mechanism for organic exports from and imports to China.

This paper aims to explore the mediating role of organizational entrepreneurial capability in the link between entrepreneurs’ effectuation and new venture performance, and whether entrepreneurs’ passion positively moderates this relationship in the Chinese emerging economy.

This study collected survey data from 140 Chinese new ventures. Following an empirical design, hierarchical regression analysis and bootstrapping analysis were applied to examine six hypotheses.

Results reveal that organizational entrepreneurial capability plays a positively mediating role in the association between entrepreneurs’ effectuation and new venture performance. Moreover, the whole mediation model is positively moderated by entrepreneurs’ passion, not only the association but also between entrepreneurs’ effectuation and organizational entrepreneurial capability.

The study is limited to the static relationships between key variables using the data obtained at one point in an emerging economy, which cannot investigate the dynamic evolution between variables. More longitudinal designs or cases to track the dynamic association should be considered.

The findings provide useful suggestions for entrepreneurs to enhance their effectual logic and entrepreneurs’ passion to better perceive and exploit opportunities and further improve new venture performance. The results also provide guidance for other groups, such as angel investors and policymakers, regarding how to use effectuation logic as an evaluation criterion to judge whether a new venture or program has investment potential.

These findings enrich the effectuation theory by providing the empirical evidence of the effect of entrepreneurs’ effectuation on new venture performance in an emerging economy. They also provide deeper insights into opportunity research by uncovering the mediating role of organizational entrepreneurial capability in the relationship between entrepreneurs’ effectuation and new venture performance.

The purpose of this paper is to develop a means of the kinematic calibration of a parallel manipulator with full-circle rotation.

An error-mapping model based on the space vector chain is formulated and parameter identification is proposed based on double ball-bar (DBB) measurements. The measurement trajectory is determined by the motion characteristics of this mechanism and whether the error sources can be identified. Error compensation is proposed by modifying the inputs, and a two-step kinematic calibration method is implemented.

The simulation and experiment results show that this kinematic calibration method is effective. The DBB length errors and the position errors in the end-effector of the parallel manipulator with full-circle rotation are greatly reduced after error compensation.

By establishing the mapping relationship between measured error data and geometric error sources, the error parameters of this mechanism are identified; thus, the pose errors are unnecessary to be measured directly. The effectiveness of the kinematic calibration method is verified by computer simulation and experiment. This proposed calibration method can help the novel parallel manipulator with full-circle rotation and other similar parallel mechanisms to improve their accuracy.

Vegetable e-commerce is of great significance for improving the efficiency of vegetable circulation, and for solving the problems of high circulation cost and poor connection between production and marketing. The purpose of this study is to explore the key factors that influence consumers’ vegetable e-commerce adoption willingness, behavior, and willingness-behavior consistency.

A total of 427 valid questionnaires were collected from 16 districts of Beijing in 2019 via the internet, yielding a response rate of 94.9%. Bivariate probit and binary logistic regression were used for analysis.

The results show that 62.84% of vegetable e-commerce consumers have the same willingness and behavior, and 37.16% of consumers have a deviation of willingness and behavior; the key factors influencing the willingness, behavior, and willingness-behavior consistency of vegetable e-commerce consumers are different. The three variables of usefulness perception, logistics service quality perception, and nearest vegetable market distance have significant effects on and are positively correlated with the adoption willingness, behavior, and willingness-behavior consistency of vegetable e-commerce consumers.

Consumers in Beijing, a first-tier city, were taken as the research object in this study. Second-tier and even third-tier cities can be investigated as comparative studies in a follow-up study. In addition, the key factors that affect the differences in the willingness and behavior of vegetable e-commerce adoption can be studied.

The results obtained in the present study and their implications could aid in vegetable e-commerce optimization, and contribute to the understanding of how to improve consumers’ awareness and participation in vegetable e-commerce. The suggestions of this study could also be used for the improvement of vegetable e-commerce in other cities facing similar issues.