Aiming at the problems of geometric precision misalignment and unconsidered physical constraints between large components during the measurement-assisted assembly, a self-adaptive…
Abstract
Purpose
Aiming at the problems of geometric precision misalignment and unconsidered physical constraints between large components during the measurement-assisted assembly, a self-adaptive alignment strategy based on the dynamic compliance center (DCC) is proposed in this paper, using force information to guide alignment compliantly.
Design/methodology/approach
First, the self-adaptive alignment process of large components is described, and its geometrical and mechanical characteristics are analyzed based on six-dimensional force/torque (F/T). The setting method of DCC is studied and the areas of DCC are given. Second, the self-adaptive alignment platform of large components driven by the measured six-dimensional F/T is constructed. Based on this platform, the key supporting technologies, including principle of self-adaptive alignment, coordinate transfer, calculation of six-dimensional F/T and alignment process control, are illustrated.
Findings
Using the presented strategy, the position and orientation of large component is adjusted adaptively responding to measured six-dimensional F/T and the changes of contact states are consistent with the strategy. Through the setting of DCC, alignment process runs smoothly without jamming.
Practical implications
This strategy is applied to the alignment experiment of large components muff coupling. The experimental results show that the proposed alignment strategy is correct and effective and meets the real-time requirement.
Originality/value
This paper proposed a novel way to apply force information in large component self-adaptive alignment, and the setting method of DCC was presented to make the alignment process more feasible.
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In the assembly process of the satellite, there will be multiple installation and disassembly operations for the solar wing and the main satellite body (or simulator). However…
Abstract
Purpose
In the assembly process of the satellite, there will be multiple installation and disassembly operations for the solar wing and the main satellite body (or simulator). However, the traditional method of orientation adjustment by theodolite and two-axis turntable is difficult to coordinate three rotation angles of yaw, pitch and roll, which leads to the complexity of actual operation and dependency on manual experience. Therefore, this paper aims to propose a new method to achieve rapid and precise orientation adjustment.
Design/methodology/approach
The similarity relation of the orientation variation matrix in a different coordinate system is studied, and a mapping model of the similarity relation is established. By using multiple element matrices to construct the original rotation matrix, the mapping is solved in quaternion form. Taking the theodolite as a measuring instrument and the Stewart platform as a control equipment, an experiment on installing the solar wing is performed to validate the effectiveness of the algorithm.
Findings
Based on the solving algorithm, the orientation adjustment process is simplified to a three-step fixed mode, which is three adjustments to get the parameter of the mapping model, one to adjust the component in place and another to further fine tuning. The final orientation deviation is less than 0.003° and close to the level of using a laser tracker, achieving the required accuracy of 0.0115°.
Originality/value
This paper reveals the similarity relation of the variation matrix in the process of orientation adjustment and presents a new method to achieve rapid and precise orientation adjustment for the large-scale component.
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Taru Saigal, Arun Kr. Vaish and N.V. Muralidhar Rao
Using survey data of a developing country city, this study aims to examine the impact of different socio-demographic factors on the choice of less-polluting modes of transport for…
Abstract
Purpose
Using survey data of a developing country city, this study aims to examine the impact of different socio-demographic factors on the choice of less-polluting modes of transport for purposes other than work.
Design/methodology/approach
Stratified random sampling technique is employed and data on socio-demographic characteristics and mode of transport used is collected. Descriptive statistics complemented with a logit model of choice probabilities is implemented on the data obtained.
Findings
Majority of the population in the city uses motorized means of transportation irrespective of the socio-demographic changes existing among them. Women, the individuals belonging to the youngest age group, the least economically well-off group of people, the least educated and the non-working are the individuals more likely to use more of less-polluting modes and less of more-polluting modes for non-work purposes as compared to their counterparts.
Research limitations/implications
The study also calls for the development of an efficient and secured system of public transportation and non-motorized transportation in the city in such a way so as to neither hamper the goal of sustainability nor the goal of empowerment.
Originality/value
To the best of the authors’ knowledge, this is the first time a comprehensive analysis of the influence of socio-demographic factors on choice of type of mode of transport is carried out in this region of the developing world. This analysis will facilitate the policy makers in catering to the transportation needs of different segments of the society.
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Hong Liu, Wenping Wang and Qishan Zhang
The purpose of this paper is to realize a multi‐objective location‐routing network optimization in reverse logistics using particle swarm optimization based on grey relational…
Abstract
Purpose
The purpose of this paper is to realize a multi‐objective location‐routing network optimization in reverse logistics using particle swarm optimization based on grey relational analysis with entropy weight.
Design/methodology/approach
Real world network design problems are often characterized by multi‐objective in reverse logistics. This has recently been considered as an additional objective for facility location problem or vehicle routing problem in reverse logistics network design. Both of them are shown to be NP‐hard. Hence, location‐routing problem (LRP) with multi‐objective is more complicated integrated problem, and it is NP‐hard too. Due to the fact that NP‐hard model cannot be solved directly, grey relational analysis and entropy weight were added to particle swarm optimization to decision among the objectives. Then, a mathematics model about multi‐objective LRP of reverse logistics has been constructed, and a proposed hybrid particle swarm optimization with grey relational analysis and entropy weight has been developed to resolve it. An example is also computed in the last part of the paper.
Findings
The results are convincing: not only that particle swarm optimization and grey relational analysis can be used to resolve multi‐objective location‐routing model, but also that entropy and grey relational analysis can be combined to decide weights of objectives.
Practical implications
The method exposed in the paper can be used to deal with multi‐objective LRP in reverse logistics, and multi‐objective network optimization result could be helpful for logistics efficiency and practicability.
Originality/value
The paper succeeds in realising both a constructed multi‐objective model about location‐routing of reverse logistics and a multi‐objective solution algorithm about particle swarm optimization and future stage by using one of the newest developed theories: grey relational analysis.
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This paper aims to collect and compile the historical data of Guanfu Salt Farm, officially built by the Song Dynasty (960–1279) within modern Hong Kong territories, to reconstruct…
Abstract
Purpose
This paper aims to collect and compile the historical data of Guanfu Salt Farm, officially built by the Song Dynasty (960–1279) within modern Hong Kong territories, to reconstruct its history for the reflection of Hong Kong society of the time.
Design/methodology/approach
This paper is largely based on identification and analysis of historical documents, including keyword search on electronic databases and verification with the original sources, with reference to archaeological findings when necessary.
Findings
This paper reconstructs the history of Guanfu Salt Farm based on documentary sources with reference to archaeological findings. English translation of Chinese sources is also provided when necessary.
Originality/value
There has been an absence of systematic compilation of historical data of Hong Kong during the Song Dynasty, which are limited in quantity and scattered across different sources. This paper seeks to fill the vacuum of knowledge about pre-colonial Hong Kong, with a more comprehensive reconstruction of the history of Guanfu Salt Farm.
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Ruipu Tan, Lehua Yang, Shengqun Chen and Wende Zhang
The Chinese believe that “man will conquer the sky” and “fighting with the sky brings endless joy”. Considering that disaster assessment can be regarded as a two-person, zero-sum…
Abstract
Purpose
The Chinese believe that “man will conquer the sky” and “fighting with the sky brings endless joy”. Considering that disaster assessment can be regarded as a two-person, zero-sum game problem between nature and human beings, this paper proposes a multi-attribute decision-making method based on game theory and grey theory in a single-value neutrosophic set environment. Due to the complexity and uncertainty of the decision-making environment, the method builds a decision matrix based on single-valued neutrosophic numbers.
Design/methodology/approach
First, the authors use the single-value neutrosophic information entropy to calculate the attribute weights and the weighted decision matrix. Second, the optimal mixed strategy method based on linear programming solves the optimal mixed strategy for both sides of the game so that the expected payoff matrix can be obtained. Finally, grey correlation analysis is used to obtain the closeness coefficient of each alternative based on the expectation payoff matrix to identify the ranking result of the alternative.
Findings
An example is used to verify the effectiveness of the proposed method, and its rationality is verified through a comprehensive comparison and analysis of the various aspects.
Practical implications
The proposed decision-making method can be applied to typhoon disaster assessment. Such assessment results can provide intelligent decision support to the relevant disaster management departments, thereby reducing the negative impact of typhoon disasters on society, stabilizing society and improving people's happiness. Further, the method can be used for decision-making, recommendation and evaluation in other fields.
Originality/value
The proposed method uses single-value neutrosophic numbers to solve the information representation problem of decision-making in a complex environment. Under a new perspective, game theory is used to handle the decision matrix, while grey relational analysis converts inexact numbers to exact numbers for comparison and sorting. Thus, the proposed method can be used to make reasonable decisions while preserving information to the extent possible.
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Yujing Liu and Meifang Li
This study explores how the high-end equipment manufacturing industry (HEMI) achieves intelligent development through the digital innovation ecosystem. While this industry…
Abstract
Purpose
This study explores how the high-end equipment manufacturing industry (HEMI) achieves intelligent development through the digital innovation ecosystem. While this industry urgently needs to achieve intelligent development through innovation breakthroughs, existing research lacks a deep analysis in conjunction with the digital innovation ecosystem. Considering the sophisticated nature of HEMI and the unique characteristics of the digital innovation ecosystem, this paper aims to uncover the innovation potential and synergetic development opportunities that arise from their integration.
Design/methodology/approach
This study uses Dynamic Qualitative Comparative Analysis (QCA) to explore the evolving relationship between the digital innovation ecosystem and intelligent development in HEMI enterprises. Data from 60 HEMI enterprises were collected from 2015 to 2022, and the study window was divided into two-year intervals for analysis. Compared to traditional QCA methods, this approach overcomes the limitations of cross-sectional analysis, fully accounting for time’s influence on causal relationships for more accurate results.
Findings
The study reveals that the digital innovation ecosystem of HEMI drives intelligent development through the coordinated interactions of its elements within each time window. Configuration paths and key driving factors evolve dynamically, reflecting the complexity of the ecosystem’s role in driving intelligent development. The study suggests that enterprises dynamically adjust their strategies to different stages, enhancing the effectiveness of intelligent transformation.
Originality/value
The paper proposes and validates a digital innovation ecosystem framework for HEMI, systematically exploring its role in driving intelligent development. The study fills a research gap and extends innovation ecosystem theory by identifying core driving factors and their evolutionary trends through Dynamic QCA. It offers a new perspective on the dynamic role of digital innovation ecosystems in intelligent transformation.
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Björn Albin, Jiang Qin and Zhang Hong
An increasing number of people are migrating within the borders of China. Some migrants have to leave their children behind, and 58,000,000 children are estimated to be living as…
Abstract
Purpose
An increasing number of people are migrating within the borders of China. Some migrants have to leave their children behind, and 58,000,000 children are estimated to be living as left‐behind children. Earlier studies have found severe mental problems in left‐behind children, but different factors could influence their mental health. The purpose of this paper is to investigate the mental health of these left‐behind children and to determine possible influencing factors.
Design/methodology/approach
Data for this study were collected in one province of the People's Republic of China with a validated instrument, the Strengths and Difficulties Questionnaire (SDQ), to investigate behavior in 13‐to‐15‐year old children.
Findings
No significant difference was found in total difficulty score and in any subscale score of SDQ when left‐behind children were compared with children who were not left behind. A significant difference in emotional difficulty subscale score was found between girls who were left behind and girls who were not. Some socio‐economic factors such as poor family economy and living with relatives, friends or grandparents, were identified as risk factors.
Originality/value
When strategies for support of the mental health in left‐behind children are developed, they will need to be individualized according to the gender, social and economic situation and focused on emotional and conduct problems.
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This study explores the characteristics of high-speed rail (HSR) and air transportation networks in China based on the weighted complex network approach. Previous related studies…
Abstract
This study explores the characteristics of high-speed rail (HSR) and air transportation networks in China based on the weighted complex network approach. Previous related studies have largely implemented unweighted (binary) network analysis, or have constructed a weighted network, limited by unweighted centrality measures. This study applies weighted centrality measures (mean association [MA], triangle betweenness centrality [TBC], and weighted harmonic centrality [WHC]) to represent traffic dynamics in HSR and air transportation weighted networks, where nodes represent cities and links represent passenger traffic. The spatial distribution of centrality results is visualized by using ArcGIS 10.2. Moreover, we analyze the network robustness of HSR, air transportation, and multimodal networks by measuring weighted efficiency (WE) subjected to the highest weighted centrality node attacks. In the HSR network, centrality results show that cities with a higher MA are concentrated in the Yangtze River Delta and the Pearl River Delta; cities with a higher TBC are mostly provincial capitals or regional centers; and cities with a higher WHC are grouped in eastern and central regions. Furthermore, spatial differentiation of centrality results is found between HSR and air transportation networks. There is a little bit of difference in eastern cities; cities in the central region have complementary roles in HSR and air transportation networks, but air transport is still dominant in western cities. The robustness analysis results show that the multimodal network, which includes both airports and high-speed rail stations, has the best connectivity and shows robustness.
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Yu-Ling Hsiao and Lucy E. Bailey
This chapter draws from a three-year ethnographic study focused on the educational and community interactions among working- and middle-class ethnic Chinese immigrants in a…
Abstract
This chapter draws from a three-year ethnographic study focused on the educational and community interactions among working- and middle-class ethnic Chinese immigrants in a mid-western town in the United States. Aihwa Ong (1999) argues that “Chineseness” is a fluid, cultural practice manifested within the Chinese diaspora in particular ways that relate to globalization in late modernity, immigrants’ cultural background, their place in the social structure in their home society, and their new social class status in the context they enter. The study extends research focused on the complexities of social reproduction within larger global flows of Chinese immigrants. First, we describe how Chinese immigrants’ social status in their countries of origin in part shapes middle and working-class group’s access to cultural capital and positions in the social structure of their post-migration context. Second, we trace groups’ negotiation of their relational race and class positioning in the new context (Ong, 1999) that is often invisible in the processes of social reproduction. Third, we describe how both groups must negotiate national, community, and schooling conceptions of the model minority concept (Lee, 1996) that shapes Asian-American’s lived realities in the United States; yet the continuing salience of their immigrant experience, home culture, and access to cultural capital (Bourdieu, 2007) means that they enact the “model minority” concept differently. The findings suggest the complexity of Chinese immigrants’ accommodation of and resistance to normative ideologies and local structures that cumulatively contribute to social reproduction on the basis of class.