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Article
Publication date: 20 April 2012

Hur‐Li Lee

This study aims to understand the epistemic foundation of the classification applied in the first Chinese library catalogue, the Seven Epitomes (Qilue).

Abstract

Purpose

This study aims to understand the epistemic foundation of the classification applied in the first Chinese library catalogue, the Seven Epitomes (Qilue).

Design/methodology/approach

Originating from a theoretical stance that situates knowledge organization in its social context, the study applies a multifaceted framework pertaining to five categories of textual data: the Seven Epitomes; biographical information about the classificationist Liu Xin; and the relevant intellectual, political, and technological history.

Findings

The study discovers seven principles contributing to the epistemic foundation of the catalogue's classification: the Han imperial library collection imposed as the literary warrant; government functions considered for structuring texts; classicist morality determining the main classificatory structure; knowledge perceived and organized as a unity; objects, rather than subjects, of concern affecting categories at the main class level; correlative thinking connecting all text categories to a supreme knowledge embodied by the Six Classics; and classicist moral values resulting in both vertical and horizontal hierarchies among categories as well as texts.

Research limitations/implications

A major limitation of the study is its focus on the main classes, with limited attention to subclasses. Future research can extend the analysis to examine subclasses of the same scheme. Findings from these studies may lead to a comparison between the epistemic approach in the target classification and the analytic one common in today's bibliographic classification.

Originality/value

The study is the first to examine in depth the epistemic foundation of traditional Chinese bibliographic classification, anchoring the classification in its appropriate social and historical context.

Details

Journal of Documentation, vol. 68 no. 3
Type: Research Article
ISSN: 0022-0418

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Article
Publication date: 9 July 2020

Xin Liu, Junhui Wu, Yiyun Man, Xibao Xu and Jifeng Guo

With the continuous development of aerospace technology, space exploration missions have been increasing year by year, and higher requirements have been placed on the…

Abstract

Purpose

With the continuous development of aerospace technology, space exploration missions have been increasing year by year, and higher requirements have been placed on the upper level rocket. The purpose of this paper is to improve the ability to identify and detect potential targets for upper level rocket.

Design/methodology/approach

Aiming at the upper-level recognition of space satellites and core components, this paper proposes a deep learning-based spatial multi-target recognition method, which can simultaneously recognize space satellites and core components. First, the implementation framework of spatial multi-target recognition is given. Second, by comparing and analyzing convolutional neural networks, a convolutional neural network model based on YOLOv3 is designed. Finally, seven satellite scale models are constructed based on systems tool kit (STK) and Solidworks. Multi targets, such as nozzle, star sensor, solar,etc., are selected as the recognition objects.

Findings

By labeling, training and testing the image data set, the accuracy of the proposed method for spatial multi-target recognition is 90.17%, which is improved compared with the recognition accuracy and rate based on the YOLOv1 model, thereby effectively verifying the correctness of the proposed method.

Research limitations/implications

This paper only recognizes space multi-targets under ideal simulation conditions, but has not fully considered the space multi-target recognition under the more complex space lighting environment, nutation, precession, roll and other motion laws. In the later period, training and detection can be performed by simulating more realistic space lighting environment images or multi-target images taken by upper-level rocket to further verify the feasibility of multi-target recognition algorithms in complex space environments.

Practical implications

The research in this paper validates that the deep learning-based algorithm to recognize multiple targets in the space environment is feasible in terms of accuracy and rate.

Originality/value

The paper helps to set up an image data set containing six satellite models in STK and one digital satellite model that simulates spatial illumination changes and spins in Solidworks, and use the characteristics of spatial targets (such as rectangles, circles and lines) to provide prior values to the network convolutional layer.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 8
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 26 July 2021

Hongxing Zheng, Xin Liu, Junhui Wu, Yiyun Man, Xibao Xu and Jifeng Guo

The purpose of this paper is to improve the efficiency of on-orbit operations through the top-level task design based on DoDAF. Based on the existing upper stage rocket…

Abstract

Purpose

The purpose of this paper is to improve the efficiency of on-orbit operations through the top-level task design based on DoDAF. Based on the existing upper stage rocket technology, orbit transfer vehicles (OTVs) have developed rapidly in recent years. However, the lack of decision guidance based on overall task analysis requires integrating top-level analysis and bottom-level execution to achieve the smooth development of full-process tasks.

Design/methodology/approach

Using the Department of Defense Architecture Framework (DoDAF) as a reference, this paper performs the top-level mission analysis modeling of the on-orbit rendezvous and capture of the OTV. Moreover, the typical operational view products are obtained, and the cooperative relations among the mission requirements, the system requirements, and the functional requirements are also analyzed.

Findings

The results show that the attitude of the OTV changes violently during the maneuver and rendezvous phases. In addition, the view products can be optimized based on the results.

Originality/value

The proposed DoDAF-based on-orbit task integration analysis method achieves the effective fusion of high-level analysis and bottom-level execution of OTV on-orbit rendezvous and capture task through the top-level task modeling, operation view generation and task relationship analysis. According to the requirements and constraints of the on-orbit rendezvous and capture task, the control instructions of the vehicle are efficiently generated under the DoDAF framework.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Open Access
Article
Publication date: 1 August 2018

Jiandong Chen, Yinyin Wu, Chong Xu, Malin Song and Xin Liu

Non-fossil fuels are receiving increasing attention within the context of addressing global climate challenges. Based on a review of non-fossil fuel consumption in major…

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Abstract

Purpose

Non-fossil fuels are receiving increasing attention within the context of addressing global climate challenges. Based on a review of non-fossil fuel consumption in major countries worldwide from 1985 to 2015, the purpose of this paper is to analyze trends for global non-fossil fuel consumption, share of fuel consumption and inequality.

Design/methodology/approach

The similarities were obtained between the logarithmic mean divisia index and the mean-rate-of-change index decomposition analysis methods, and a method was proposed for complete decomposition of the incremental Gini coefficient.

Findings

Empirical analysis showed that: global non-fossil fuel consumption accounts for a small share of the total energy consumption, but presents an increasing trend; the level of global non-fossil fuel consumption inequality is high but has gradually declined, which is mainly attributed to the concentration effect; inequality in global non-fossil fuel consumption is mainly due to the difference between nuclear power and hydropower consumption, but the contributions of nuclear power and hydropower to per capita non-fossil fuel consumption are declining; and population has the greatest influence on global non-fossil fuel consumption during the sampling period.

Originality/value

The main contribution of this study is its analysis of global non-fossil fuel consumption trends, disparities and driving factors. In addition, a general formula for complete index decomposition is proposed and the incremental Gini coefficient is wholly decomposed.

Details

Management Decision, vol. 57 no. 4
Type: Research Article
ISSN: 0025-1747

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Article
Publication date: 14 August 2017

Xin Liu, Jing Hu and Bing Xu

The purpose of this study is to find out how electronic word of mouth (eWOM) may affect evaluations of products with different brand images. In particular, the study…

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2086

Abstract

Purpose

The purpose of this study is to find out how electronic word of mouth (eWOM) may affect evaluations of products with different brand images. In particular, the study explores differential eWOM impacts across several brand types and extension categories.

Design/methodology/approach

An experiment with 2 (brand image: prestige/function) × 2 (category similarity: low/high) × 2 (eWOM message type: positive/negative) between-subjects design was used to examine the impacts of eWOM on different types of brand extensions. A total of 268 subjects from a public university in the Southwest participated in the study. Analysis of Variance (ANOVA) was used in analyzing the data.

Findings

The findings highlight the differential impact of eWOM on brand extension evaluations with different brand images. First, eWOM is more effective in influencing evaluations of functional brand extensions than prestige brand extensions. Second, whereas negative eWOM does equally bad on both high- and low-similarity brand extensions, positive eWOM is more effective in improving evaluations of high-similarity extensions than low-similarity extensions.

Originality/value

This study is the first to examine the impact of eWOM on products with different brand images. This is a critical issue for brand managers who allocate limited marketing resources to monitoring and managing vast amounts of eWOM activities. The findings provide important guidance for managing social media marketing communications.

Details

Journal of Research in Interactive Marketing, vol. 11 no. 3
Type: Research Article
ISSN: 2040-7122

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Article
Publication date: 12 June 2017

Liming Zhai, Yongyao Luo, Xin Liu, Funan Chen, Yexiang Xiao and Zhengwei Wang

The purpose of this paper is to analyze lubrication characteristics of a tilting pad thrust bearing considering the effect of the thermal elastic deformation of the pad and collar.

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372

Abstract

Purpose

The purpose of this paper is to analyze lubrication characteristics of a tilting pad thrust bearing considering the effect of the thermal elastic deformation of the pad and collar.

Design/methodology/approach

This study used the fluid–solid interaction (FSI) technique to investigate the lubrication characteristics of a tilting pad thrust bearing for several typical operating conditions. The influences of the rotational speed, the thrust load and the oil supply temperature on the lubrication characteristics were analyzed.

Findings

The three-dimensional (3D) film model clearly shows that there is no pressure gradient but large temperature gradients across the film thickness. The wall heat transfer coefficients on the pad surfaces distribute in a very complex way and change within a large range. The rotational speed, the thrust load and the oil supply temperature have great but different influences on the lubrication characteristics.

Originality/value

This paper has preliminarily revealed the lubrication mechanism of the tilting-pad thrust bearings. The 3D FSI method is suggested to evaluate the thermal-elastic-hydrodynamic deformations of thrust bearings instead of the conventional method which iteratively solves the Reynolds equation, the energy equation, the heat conduction equation and the elastic equilibrium equation. Using FSI method, the heat transfer coefficients on the pad surfaces can be evaluated better.

Details

Engineering Computations, vol. 34 no. 4
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 20 February 2019

Guisheng Gan, Da-quan Xia, Xin Liu, Cong Liu, Hanlin Cheng, Zhongzhen Ming, Haoyang Gao, Dong-hua Yang and Yi-ping Wu

With continuous concerning on the toxic of element Pb, Pb-free solder was gradually used to replace traditional Sn-Pb solder. However, during the transition period from…

Abstract

Purpose

With continuous concerning on the toxic of element Pb, Pb-free solder was gradually used to replace traditional Sn-Pb solder. However, during the transition period from Sn-Pb to Pb-free solder, mixing of Sn-Pb and Pb-free is inevitable occurred in certain products, and in China where Sn-Pb solder was still used extensively in certain areas especially. Correspondingly, understanding reliability of Sn-Pb solder joints was very important, and further studies were needed.

Design/methodology/approach

Thermal shock test between −55°C and 125 °C was conducted on Sn-37Pb solder bumps in the BGA package to investigate the microstructure evolution and the growth mechanism of interfacial intermetallic compound (IMC) layer. The effects of thermal shock on the mechanical property and fracture behavior of Sn-37Pb solder bumps were discussed.

Findings

Pb-rich phase was coarsened and voids were increased at first; Pb-rich phase was refined and voids were decreased secondly with the increase of thermal shock cycles; the shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67MPa at 2,000 cycles; interfacial IMCs of solder bumps was from typical scallop-type into smooth, the composition of IMCs was from Cu6Sn5 into Cu6Sn5 and Cu3Sn after thermal shock with 1,500 and 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure respectively.

Originality/value

Compared with the board level test method, the impact shear test for the single solder bump is more convenient and economical and is actively pursued by the industries. The shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67 MPa at 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure.

Details

Soldering & Surface Mount Technology, vol. 31 no. 2
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 9 May 2019

Jih-Yu Mao, Ye Zhang, Lifan Chen and Xin Liu

The purpose of this paper is to investigate the negative consequences of employee perceptions of supervisor self-interested behavior (SIB). Using social exchange theory…

Abstract

Purpose

The purpose of this paper is to investigate the negative consequences of employee perceptions of supervisor self-interested behavior (SIB). Using social exchange theory, the authors argue that perceived supervisor SIB reduces affective commitment to the supervisor (ACS), which in turn fosters employees’ negative reciprocal behavior in the form of counterproductive work behavior – interpersonal (CWBI) and counterproductive work behavior – organizational (CWBO). In addition, the authors identify employee power distance orientation (PDO) as an important contingent factor that influences the indirect effects.

Design/methodology/approach

Using a final sample of 441 employees from 146 workgroups across 6 firms in China, the hypotheses are tested using multilevel path analysis to account for the nesting effects.

Findings

Perceived supervisor SIB is negatively related to ACS, which in turn is related to employee CWBI and CWBO. Furthermore, employee PDO moderates the indirect effects of perceived supervisor SIB on employee CWBI and CWBO through decreased ACS. Specifically, when employee PDO is low, the indirect effects on employee CWBI and CWBO are stronger.

Originality/value

This is one of the first studies to investigate the influence of employee perceptions of supervisor SIB on negative employee behavior in the workplace. Furthermore, it furthers our understanding of how negative exchange can stimulate negative reciprocal behavior, which is a relatively underexplored area. Another strength of this paper is the multi-time survey design and the adoption of multilevel path analysis.

Details

Journal of Managerial Psychology, vol. 34 no. 3
Type: Research Article
ISSN: 0268-3946

Keywords

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Article
Publication date: 19 June 2019

Xin Liu, Hang Zhang, Pengbo Zhu, Xianqiang Yang and Zhiwei Du

This paper aims to investigate an identification strategy for the nonlinear state-space model (SSM) in the presence of an unknown output time-delay. The equations to…

Abstract

Purpose

This paper aims to investigate an identification strategy for the nonlinear state-space model (SSM) in the presence of an unknown output time-delay. The equations to estimate the unknown model parameters and output time-delay are derived simultaneously in the proposed strategy.

Design/methodology/approach

The unknown integer-valued time-delay is processed as a latent variable which is uniformly distributed in a priori known range. The estimations of the unknown time-delay and model parameters are both realized using the Expectation-Maximization (EM) algorithm, which has a good performance in dealing with latent variable issues. Moreover, the particle filter (PF) with an unknown time-delay is introduced to calculated the Q-function of the EM algorithm.

Findings

Although amounts of effective approaches for nonlinear SSM identification have been developed in the literature, the problem of time-delay is not considered in most of them. The time-delay is commonly existed in industrial scenario and it could cause extra difficulties for industrial process modeling. The problem of unknown output time-delay is considered in this paper, and the validity of the proposed approach is demonstrated through the numerical example and a two-link manipulator system.

Originality/value

The novel approach to identify the nonlinear SSM in the presence of an unknown output time-delay with EM algorithm is put forward in this work.

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Article
Publication date: 5 May 2015

Xian Xin, Tun Lin, Xiaoyun Liu, Guanghua Wan and Yongsheng Zhang

The impacts of climate change on agricultural production in the People’s Republic of China’s (PRC) are significant, and differ across regions and crops. The substantial…

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3258

Abstract

Purpose

The impacts of climate change on agricultural production in the People’s Republic of China’s (PRC) are significant, and differ across regions and crops. The substantial regional differences will induce changes in agricultural interregional trade pattern. The purpose of this paper is to investigate the climate change impacts on China’s agricultural interregional trade pattern.

Design/methodology/approach

The paper will use the computable general equilibrium (CGE) model to assess the impacts of climate change on the PRC’s agricultural interregional trade flows. The CGE model consists of seven Chinese regions and the rest of the world and six commodities.

Findings

The results indicate that northwest, south, central, and northeast PRC will see increases in the outflows of agricultural products in 2030 and 2050. Conversely, outflows from east, north, and southwest PRC will decrease. Agricultural products handling and transportation facilities need to be repositioned to address the changes in agricultural trade flows.

Originality/value

Studies on the impacts of climate change on the PRC’s agriculture have been increasing. To the best of our knowledge, however, no previous studies have assessed the impacts of climate change on the PRC’s agricultural interregional trade flows. This paper aims to fill this gap in the literature.

Details

China Agricultural Economic Review, vol. 7 no. 2
Type: Research Article
ISSN: 1756-137X

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