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Article
Publication date: 6 November 2017

Jiajia Chen, Yuhan Ma and Shiyou Yang

The purpose of this paper is to provide an accurate model and method to simulate the transient performances of an insulated gate bipolar transistor (IGBT) in an arbitrary…

Abstract

Purpose

The purpose of this paper is to provide an accurate model and method to simulate the transient performances of an insulated gate bipolar transistor (IGBT) in an arbitrary free-carrier injection condition.

Design/methodology/approach

A numerical model and method for solving the physics-based model, an ambipolar diffusion equation-based model, of an IGBT is proposed.

Findings

The results of the proposed model are very close to the tested ones.

Originality/value

A mathematical model for an IGBT considering all free-carrier injection conditions is introduced, and a numerical solution methodology is proposed.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 19 June 2017

Jiajia Chen, Wuhua Jiang, Pan Zhao and Jinfang Hu

Navigating in off-road environments is a huge challenge for autonomous vehicles, due to the safety requirement, the effects of noises and non-holonomic constraints of…

Abstract

Purpose

Navigating in off-road environments is a huge challenge for autonomous vehicles, due to the safety requirement, the effects of noises and non-holonomic constraints of vehicle. This paper aims to describe a path planning method based on fuzzy support vector machine (FSVM) and general regression neural network (GRNN) that is able to provide a solution path for the autonomous vehicle navigating in the off-road environments.

Design/methodology/approach

The authors decompose the path planning problem into three steps. In the first step, A* algorithm is applied to obtain the positive and negative samples. In the second step, the authors use a learning approach based on radial basis function kernel FSVM to maximize the safety margin for driving, and the fuzzy membership is designed based on GRNN which can help to resolve the problem that the traditional path planning method is easily influenced by noises or outliers. In the third step, the Bezier interpolation algorithm is used to smooth the path. The simulations are designed to verify the parameters of the path planning algorithm.

Findings

The method is implemented on autonomous vehicle and verified against many outdoor scenes. Road test indicates that the proposed method can produce a flexible, smooth and safe path with good anti-jamming performance.

Originality/value

This paper applied a new path planning method based on GRNN-FSVM for autonomous vehicle navigating in off-road environments. GRNN-FSVM can reduce the effects of outliers and maximize the safety margin for driving, the generated path is smooth and safe, while satisfying the constraint of vehicle kinematic.

Details

Industrial Robot: An International Journal, vol. 44 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 August 2016

Jiajia Chen, Rong Zhang and Bin Liu

The purpose of this paper is to find the key influence factors of executive compensation within China ports and listed shipping companies and provide some reasonable…

Abstract

Purpose

The purpose of this paper is to find the key influence factors of executive compensation within China ports and listed shipping companies and provide some reasonable suggestions. Eventually, help to perfect the executive compensation evaluation mechanism against the background of new area.

Design/methodology/approach

Grey correlation analysis is an important part of grey system theory. Professor Liu Sifeng further studies the relationship between two sequences absolute increment on the basis of Deng’s degree and put forward the “Grey absolute correlation degree,” which is widely used in practice. In the study, on the basis of the area of the line between sequences size, it measures the correlation degrees of firm performance, executive stock holding, continuous growth capacity and other relevant factors of executive payment in China ports and listed shipping companies.

Findings

The paper concludes that the main factors influence CEO salary in China ports and listed shipping companies are return on equity and growth rate of fixed assets. However, the authors consider the frequent occurrence of executives’ corruption in China listed state-owned enterprise under the environment of financial and economic crisis, the authors argue that the significant influence of net assets attributed to shareholders cannot be ignored. In addition, cash flow in operating activities and executive stock holding both have relatively important effect on executive compensation.

Research limitations/implications

This paper still has some limitations. First, it merely takes into account the financial indicators and ignores the influence of non-financial indicators to the performance evaluation of listed companies, such as: innovation ability, human capital and goodwill. Second, it has not considered the power consumption and other types of “invisible income” in the executive compensation structure, neither the influence of investing and financing activities on corporate performance. Consequently, these are likely to cause a certain deviation to the results of the study.

Practical implications

The outcome obtained in this paper can be provided for China ports and listed shipping companies to establish a reasonable executive compensation evaluation and incentive mechanism under the background of depressed shipping market.

Social implications

This paper intends to use correlation analysis between firm performance, executive stock holding, sustainability and executive compensation in the new area of time, tries to make a greater contribution to the major component of salary policy and then make some suggestions on incentive supervising and restraining mechanisms for the ports and listed shipping firms in China.

Originality/value

Although scholars have done many studies about the association analysis of executive compensation and firm performance, they neglect the economic environment of industry. Meanwhile, considering the non-financial indicators and incomplete information, this paper studies the grey correlation analysis of executive compensation and influence factors in China ports and listed shipping firms under the background of the Chinese flagging shipping industry.

Book part
Publication date: 17 June 2020

Vilma Seeberg

The human development and capability approach (HDCA) and its associated participatory method is receiving growing attention as a useful conceptual development for…

Abstract

The human development and capability approach (HDCA) and its associated participatory method is receiving growing attention as a useful conceptual development for comparative international education. HDCA challenges the economism so prevalent in world development thinking and, instead, looks at development as a process of enhancing persons’ incrementally achieved substantive freedoms from deprivations. The centrality of the person replaces the centrality of income growth.

The application of HDCA to the study of the role of education that promotes social justice change is illustrated by using an empowerment-capability framework to the long-term study of the benefits of village schooling for rural girls in western China.

Using HDCA to identify influences on social change, we derive a much more nuanced and valuable multi-dimensional view of human development, which enables us to draw broad implications for more effective policy. National policies should use a multi-dimensional informational base including equality, sustainability, and non-market dimensions of well-being as well as market production.

Article
Publication date: 14 July 2022

Lixuan Jiang, Hua Zhong, Jianghong Chen, Jiajia Cheng, Shilong Chen, Zili Gong, Zhihui Lun, Jinhua Zhang and Zhenmin Su

The construction industry is facing challenges not only for workers' mobility in the pandemic situation but also for Lean Construction (LC) practise in responding to the…

Abstract

Purpose

The construction industry is facing challenges not only for workers' mobility in the pandemic situation but also for Lean Construction (LC) practise in responding to the high-quality development during the post-pandemic. As such, this paper presents a construction workforce management framework based on LC to manage both the emergency goal in migrant worker management and the long-term goal in labour productivity improvement in China.

Design/methodology/approach

The framework is created based on the integrated culture and technology strategies of LC. A combination of qualitative and quantitative methods is taken to explore factors influencing the mobility of construction workers and to measure labour productivity improvement. The case study approach is adopted to demonstrate the framework application.

Findings

For method application, a time-and-motion study and Percent Plan Complete indicator are proposed to offer labour productivity measurements of “resources efficiency” and “flow efficiency”. Moreover, the case study provides an industry level solution for construction workforce management and Lean Construction culture shaping, as well as witnesses the LC culture and technology strategies alignment contributing to LC practise innovation.

Originality/value

Compared with previous studies which emphasised solely LC techniques rather than socio-technical system thinking, the proposed integration framework as well as implementation of “Worker's Home” and “Lean Work Package” management models in the COVID-19 pandemic contribute to new extensions of both the fundamental of knowledge and practise in LC.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 14 July 2020

Hongjuan Yang, Jiwen Chen, Chen Wang, Jiajia Cui and Wensheng Wei

The implied assembly constraints of a computer-aided design (CAD) model (e.g. hierarchical constraints, geometric constraints and topological constraints) represent an…

Abstract

Purpose

The implied assembly constraints of a computer-aided design (CAD) model (e.g. hierarchical constraints, geometric constraints and topological constraints) represent an important basis for product assembly sequence intelligent planning. Assembly prior knowledge contains factual assembly knowledge and experience assembly knowledge, which are important factors for assembly sequence intelligent planning. This paper aims to improve monotonous assembly sequence planning for a rigid product, intelligent planning of product assembly sequences based on spatio-temporal semantic knowledge is proposed.

Design/methodology/approach

A spatio-temporal semantic assembly information model is established. The internal data of the CAD model are accessed to extract spatio-temporal semantic assembly information. The knowledge system for assembly sequence intelligent planning is built using an ontology model. The assembly sequence for the sub-assembly and assembly is generated via attribute retrieval and rule reasoning of spatio-temporal semantic knowledge. The optimal assembly sequence is achieved via a fuzzy comprehensive evaluation.

Findings

The proposed spatio-temporal semantic information model and knowledge system can simultaneously express CAD model knowledge and prior knowledge for intelligent planning of product assembly sequences. Attribute retrieval and rule reasoning of spatio-temporal semantic knowledge can be used to generate product assembly sequences.

Practical implications

The assembly sequence intelligent planning example of linear motor highlights the validity of intelligent planning of product assembly sequences based on spatio-temporal semantic knowledge.

Originality/value

The spatio-temporal semantic information model and knowledge system are built to simultaneously express CAD model knowledge and assembly prior knowledge. The generation algorithm via attribute retrieval and rule reasoning of spatio-temporal semantic knowledge is given for intelligent planning of product assembly sequences in this paper. The proposed method is efficient because of the small search space.

Details

Assembly Automation, vol. 40 no. 5
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 7 August 2021

Bochun Xu, Nan Zou, Yunhao Jia, Chao Feng, Jiajia Bu, Yu Yan and Zhipeng Xing

The purpose of this paper is to study the effect of micro-nano surface texture on the corrosion resistance of a titanium alloy and investigate the correlation between…

Abstract

Purpose

The purpose of this paper is to study the effect of micro-nano surface texture on the corrosion resistance of a titanium alloy and investigate the correlation between corrosion resistance and hydrophobicity.

Design/methodology/approach

The surface of the Ti6Al4V alloy was modified by laser processing and anodizing to fabricate micro-pits, nanotubes and micro-nano surface textures. Afterward, the surface morphology, hydrophobicity and polarization curve of the samples were analyzed by cold field scanning electron microscopy, contact angle measurement instruments and a multi-channel electrochemical workstation.

Findings

The micro-nano surface texture can enhance the hydrophobicity of the Ti6Al4V surface, which may lead to better drag reduction to ease the friction of implants in vivo. Nevertheless, no correlation existed between surface hydrophobicity and corrosion resistance; the corrosion resistance of samples with nanotubes and high-density samples with micro-nano surface texture was extremely enhanced, indicating the similar corrosion resistance of the two.

Research limitations/implications

The mechanism of micro-dimples on the corrosion resistance of the micro-nano surface texture was not studied.

Practical implications

The density of micro-pits needs to be optimized to guarantee excellent corrosion resistance in the design of the micro-nano surface texture; otherwise, it will not fulfill the requirement of surface modification.

Originality/value

The influence of the micro-nano surface texture on the corrosion resistance, as well as the relationship between hydrophobicity and corrosion resistance of the titanium alloy surface, were systematically investigated for the first time. These conclusions offer new knowledge.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 23 August 2019

Yiqun Kuang, Hong Cheng, Yali Zheng, Fang Cui and Rui Huang

This paper aims to present a one-shot gesture recognition approach which can be a high-efficient communication channel in human–robot collaboration systems.

Abstract

Purpose

This paper aims to present a one-shot gesture recognition approach which can be a high-efficient communication channel in human–robot collaboration systems.

Design/methodology/approach

This paper applies dynamic time warping (DTW) to align two gesture sequences in temporal domain with a novel frame-wise distance measure which matches local features in spatial domain. Furthermore, a novel and robust bidirectional attention region extraction method is proposed to retain information in both movement and hold phase of a gesture.

Findings

The proposed approach is capable of providing efficient one-shot gesture recognition without elaborately designed features. The experiments on a social robot (JiaJia) demonstrate that the proposed approach can be used in a human–robot collaboration system flexibly.

Originality/value

According to previous literature, there are no similar solutions that can achieve an efficient gesture recognition with simple local feature descriptor and combine the advantages of local features with DTW.

Details

Assembly Automation, vol. 40 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 20 May 2020

Shihao Li, Hongxia Zhang, Xuefang Wang and Guoqun Fu

This article investigated the relationship between loneliness and anthropomorphic products.

Abstract

Purpose

This article investigated the relationship between loneliness and anthropomorphic products.

Design/methodology/approach

The authors conducted three studies to examine their hypotheses.

Findings

The authors confirmed that highly lonely people would like to seek for social relationship. What's more, they may try to compensate by creating a sense of connection with nonhuman products so they will prefer anthropomorphic products. Further, the authors demonstrated that information framework can moderate this effect. Highly lonely consumers would increase their preference to anthropomorphic product under promotion-focus information, whereas they would decrease their preference to anthropomorphic product under prevention-focus information. These effects do not exist in lowly lonely consumers. At the same time, the authors demonstrate that the effect is mediated by perceived social connection.

Originality/value

This article contributes to loneliness literature in the consumer behavior field and proves the moderation effect of the information framework, which can deepen our understanding of the relationship between loneliness and anthropomorphic products.

Details

Journal of Contemporary Marketing Science, vol. 3 no. 1
Type: Research Article
ISSN: 2516-7480

Keywords

Article
Publication date: 12 April 2022

Hamidreza Vosoughifar, S. Farzadi and SZ. Hosseininejad

Lean management has been used in various constructions around the world for more than a quarter of a century, and it is an important factor in the construction of new…

Abstract

Purpose

Lean management has been used in various constructions around the world for more than a quarter of a century, and it is an important factor in the construction of new projects. In relation to demolition management, only standards and codes and general principles of demolition of specific buildings were evaluated. The purpose of this study is providing relation between lean management on demolition processes of municipality buildings evaluated.

Design/methodology/approach

This study investigates the lean demolition of demolished and renovated buildings in a metropolitan area that can be extended to all cities. In the first stage, the effective factors in the demolition of the building based on lean management were identified through a valid questionnaire based on the valid Delphi approach. Social, economic and environmental considerations were considered in designing the appropriate questionnaire.

Findings

The modified approach between the fuzzy method and partial least squares was used to evaluate important variables. All of the modified processes were developed in MATLAB by the authors of this paper. The results show that customer-focused degradation parameter has the weakest effect and waste removal variable has the most effect on lean management.

Originality/value

Statistical results show that there is no significant difference between the effect of lean management on variables such as demolition time, quality and type of construction (p < 0.05).

Details

Journal of Facilities Management , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1472-5967

Keywords

1 – 10 of 12