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Article
Publication date: 23 May 2018

Wei Zhang, Xianghong Hua, Kegen Yu, Weining Qiu, Shoujian Zhang and Xiaoxing He

This paper aims to introduce the weighted squared Euclidean distance between points in signal space, to improve the performance of the Wi-Fi indoor positioning. Nowadays, the…

342

Abstract

Purpose

This paper aims to introduce the weighted squared Euclidean distance between points in signal space, to improve the performance of the Wi-Fi indoor positioning. Nowadays, the received signal strength-based Wi-Fi indoor positioning, a low-cost indoor positioning approach, has attracted a significant attention from both academia and industry.

Design/methodology/approach

The local principal gradient direction is introduced and used to define the weighting function and an average algorithm based on k-means algorithm is used to estimate the local principal gradient direction of each access point. Then, correlation distance is used in the new method to find the k nearest calibration points. The weighted squared Euclidean distance between the nearest calibration point and target point is calculated and used to estimate the position of target point.

Findings

Experiments are conducted and the results indicate that the proposed Wi-Fi indoor positioning approach considerably outperforms the weighted k nearest neighbor method. The new method also outperforms support vector regression and extreme learning machine algorithms in the absence of sufficient fingerprints.

Research limitations/implications

Weighted k nearest neighbor approach, support vector regression algorithm and extreme learning machine algorithm are the three classic strategies for location determination using Wi-Fi fingerprinting. However, weighted k nearest neighbor suffers from dramatic performance degradation in the presence of multipath signal attenuation and environmental changes. More fingerprints are required for support vector regression algorithm to ensure the desirable performance; and labeling Wi-Fi fingerprints is labor-intensive. The performance of extreme learning machine algorithm may not be stable.

Practical implications

The new weighted squared Euclidean distance-based Wi-Fi indoor positioning strategy can improve the performance of Wi-Fi indoor positioning system.

Social implications

The received signal strength-based effective Wi-Fi indoor positioning system can substitute for global positioning system that does not work indoors. This effective and low-cost positioning approach would be promising for many indoor-based location services.

Originality/value

A novel Wi-Fi indoor positioning strategy based on the weighted squared Euclidean distance is proposed in this paper to improve the performance of the Wi-Fi indoor positioning, and the local principal gradient direction is introduced and used to define the weighting function.

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Article
Publication date: 5 October 2015

Zheng Jiang, Haobo Qiu, Ming Zhao, Shizhan Zhang and Liang Gao

In multidisciplinary design optimization (MDO), if the relationships between design variables and some output parameters, which are important performance constraints, are complex…

350

Abstract

Purpose

In multidisciplinary design optimization (MDO), if the relationships between design variables and some output parameters, which are important performance constraints, are complex implicit problems, plenty of time should be spent on computationally expensive simulations to identify whether the implicit constraints are satisfied with the given design variables during the optimization iteration process. The purpose of this paper is to propose an ensemble of surrogates-based analytical target cascading (ESATC) method to tackle such MDO engineering design problems with reduced computational cost and high optimization accuracy.

Design/methodology/approach

Different surrogate models are constructed based on the sample point sets obtained by Latin hypercube sampling (LHS) method. Then, according to the error metric of each surrogate model, the repeated ensemble of surrogates is constructed to approximate the implicit objective functions and constraints. Under the framework of analytical target cascading (ATC), the MDO problem is decomposed into several optimization subproblems and the function of analysis module of each subproblem is simulated by repeated ensemble of surrogates, working together to find the optimum solution.

Findings

The proposed method shows better modeling accuracy and robustness than other individual surrogate model-based ATC method. A numerical benchmark problem and an industrial case study of the structural design of a super heavy vertical lathe machine tool are utilized to demonstrate the accuracy and efficiency of the proposed method.

Originality/value

This paper integrates a repeated ensemble method with ATC strategy to construct the ESATC framework which is an effective method to solve MDO problems with implicit constraints and black-box objectives.

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Article
Publication date: 14 May 2024

Xuemei Tang, Jun Wang and Qi Su

Recent trends have shown the integration of Chinese word segmentation (CWS) and part-of-speech (POS) tagging to enhance syntactic and semantic parsing. However, the potential…

92

Abstract

Purpose

Recent trends have shown the integration of Chinese word segmentation (CWS) and part-of-speech (POS) tagging to enhance syntactic and semantic parsing. However, the potential utility of hierarchical and structural information in these tasks remains underexplored. This study aims to leverage multiple external knowledge sources (e.g. syntactic and semantic features, lexicons) through various modules for the joint task.

Design/methodology/approach

We introduce a novel learning framework for the joint CWS and POS tagging task, utilizing graph convolutional networks (GCNs) to encode syntactic structure and semantic features. The framework also incorporates a pre-defined lexicon through a lexicon attention module. We evaluate our model on a range of public corpora, including CTB5, PKU and UD, the novel ZX dataset and the comprehensive CTB9 dataset.

Findings

Experimental results on these benchmark corpora demonstrate the effectiveness of our model in improving the performance of the joint task. Notably, we find that syntax information significantly enhances performance, while lexicon information helps mitigate the issue of out-of-vocabulary (OOV) words.

Originality/value

This study introduces a comprehensive approach to the joint CWS and POS tagging task by combining multiple features. Moreover, the proposed framework offers potential adaptability to other sequence labeling tasks, such as named entity recognition (NER).

Details

Aslib Journal of Information Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2050-3806

Keywords

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Book part
Publication date: 17 October 2022

Stefania Boglietti, Martina Carra, Massimiliano Sotgiu, Benedetto Barabino, Michela Bonera and Giulio Maternini

Nowadays, the increase in the capacity of batteries has laid the foundations for a broader diffusion of electric mobility. However, electric mobility is causing a growing

Abstract

Nowadays, the increase in the capacity of batteries has laid the foundations for a broader diffusion of electric mobility. However, electric mobility is causing a growing electricity demand as well as the need to increase the diffusion of suitable charging stations. Within these last challenges, drawing on the recent literature, this chapter provides a critical and wide-ranging review of papers dealing with the formulation of the problem of the localisation of electric vehicle (EV) charging points. This problem is approached considering the electric charging infrastructure technologies, localisation criteria and related methodologies. This review shows how the ‘electric mobility revolution’ applies the technological innovations provided by the energy supply systems, and the location of these systems within the urban contexts. Since the technological innovations have different options, achieving an international standard of charging systems is still far away. Moreover, as there are several criteria, parameters and methodologies, and some analytical approaches for the localisation of electric vehicle charging points, the formulation of the ‘localisation’ problem should require the application of multi-criteria analysis to be addressed. Finally, the results show that there is no consensus on technologies, criteria, and methodologies to be adopted. Therefore, this wide-ranging analysis of the literature would be useful to support possible benchmarking and systematisation accordingly.

Details

Electrifying Mobility: Realising a Sustainable Future for the Car
Type: Book
ISBN: 978-1-83982-634-4

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Article
Publication date: 8 February 2016

Xinhua Ni, Yunwei Fu, Xiequan Liu and Long Zhang

This paper aims to promote a strength model for TiC-TiB2 composite ceramic with non-ellipsoidal particles bridging. Based on the microstructure of TiC-TiB2 composite ceramic…

69

Abstract

Purpose

This paper aims to promote a strength model for TiC-TiB2 composite ceramic with non-ellipsoidal particles bridging. Based on the microstructure of TiC-TiB2 composite ceramic, equivalent average residual stress under particles interaction is calculated with the interact direct derivative estimate. Supposing the crack opening displacement keeps ellipsoidal under the TiB2 particles bridging, crack growth resistance curve is obtained.

Design/methodology/approach

Composite strength under R-cure with crack unstable propagation is calculated. Based on this model, influences of particles volume fraction, shape, size and other parameters on strength are analyzed.

Findings

Results indicated that calculated values are consistent to the tested data. Crack growth resistance increases with crack propagation and TiB2 volume fraction. The TiB2 particle does not pull-out entirely even ceramic fracture. Ceramic strength increases with the TiB2 particle volume fraction, the ratio of platelet diameter and thickness, and it reduces with particle thickness.

Originality/value

Supposing the crack open displacement keeps ellipsoidal under the TiB2 particles bridging, crack growth resistance curve is obtained.

Details

World Journal of Engineering, vol. 13 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

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Article
Publication date: 15 June 2011

R. Liu, S. Guo, X. Qiu and J. Wang

Nanostructured reactive foils have attracted a great deal of interest recently due to their unique mechanical and thermal properties. Reactive thin foil can be used as a…

74

Abstract

Nanostructured reactive foils have attracted a great deal of interest recently due to their unique mechanical and thermal properties. Reactive thin foil can be used as a controllable, localized heating source for joining applications, which enable soldering and brazing of materials at room temperature. In this paper, multiphysics-based numerical simulations were performed to simulate reactive thin foils. The conductive heat transfer equation and mass diffusion equations were solved for 1D, 2D, and 3D cases. 1D simulation examined the effect of the chemical reaction rate on the flame speed; 2D simulation gave the detailed temperature and composition distribution in the bi-layers; and 3D simulation demonstrated the localized heating effect of reactive thin foils on a silicon wafer substrate.

Details

World Journal of Engineering, vol. 8 no. 2
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 22 August 2024

Jiawei Liu, Zi Xiong, Yi Jiang, Yongqiang Ma, Wei Lu, Yong Huang and Qikai Cheng

Fine-tuning pre-trained language models (PLMs), e.g. SciBERT, generally require large numbers of annotated data to achieve state-of-the-art performance on a range of NLP tasks in…

77

Abstract

Purpose

Fine-tuning pre-trained language models (PLMs), e.g. SciBERT, generally require large numbers of annotated data to achieve state-of-the-art performance on a range of NLP tasks in the scientific domain. However, obtaining fine-tuning data for scientific NLP tasks is still challenging and expensive. In this paper, the authors propose the mix prompt tuning (MPT), which is a semi-supervised method aiming to alleviate the dependence on annotated data and improve the performance of multi-granularity academic function recognition tasks.

Design/methodology/approach

Specifically, the proposed method provides multi-perspective representations by combining manually designed prompt templates with automatically learned continuous prompt templates to help the given academic function recognition task take full advantage of knowledge in PLMs. Based on these prompt templates and the fine-tuned PLM, a large number of pseudo labels are assigned to the unlabelled examples. Finally, the authors further fine-tune the PLM using the pseudo training set. The authors evaluate the method on three academic function recognition tasks of different granularity including the citation function, the abstract sentence function and the keyword function, with data sets from the computer science domain and the biomedical domain.

Findings

Extensive experiments demonstrate the effectiveness of the method and statistically significant improvements against strong baselines. In particular, it achieves an average increase of 5% in Macro-F1 score compared with fine-tuning, and 6% in Macro-F1 score compared with other semi-supervised methods under low-resource settings.

Originality/value

In addition, MPT is a general method that can be easily applied to other low-resource scientific classification tasks.

Details

The Electronic Library , vol. 42 no. 6
Type: Research Article
ISSN: 0264-0473

Keywords

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Book part
Publication date: 4 November 2021

Rajesh Singh and Kyle N. Brinster

While LIS scholarship emphasizes the need to be multi-literate by equipping people with critical information literacy, digital literacy, and media literacy skills to combat the…

Abstract

While LIS scholarship emphasizes the need to be multi-literate by equipping people with critical information literacy, digital literacy, and media literacy skills to combat the phenomenon of fake news in the contemporary information society, the concept of political information literacy is still in its infancy. This chapter addresses this gap by developing an understanding of political information literacy and challenges the premise that information professionals and information organizations should remain neutral in the face of phenomena like censorship through noise and disinformation. In this endeavor, it reviews contemporary information environments vis-à-vis the growth of fake news and misinformation, and current information literacy approaches utilized by information organizations. Thereafter, it explores several cognitive barriers, such as the role of confirmation bias, information avoidance, information groupishness, and information overload, which affects people’s ability to process information. Finally, it encourages information professionals to hold regular information sessions on politically charged topics, tackle the cognitive factors increasing misinformation, and cultivate multidisciplinary approaches to confront fake news.

Details

Libraries and the Global Retreat of Democracy: Confronting Polarization, Misinformation, and Suppression
Type: Book
ISBN: 978-1-83982-597-2

Keywords

Available. Open Access. Open Access
Article
Publication date: 29 February 2024

Guanchen Liu, Dongdong Xu, Zifu Shen, Hongjie Xu and Liang Ding

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous…

848

Abstract

Purpose

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Design/methodology/approach

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

Findings

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

Originality/value

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. 5 no. 1
Type: Research Article
ISSN: 2633-6596

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Article
Publication date: 16 May 2023

Sadia Aziz and Muhammad Abdullah Khan Niazi

Tourists’ irresponsible behaviours (e.g. damaging flowers, writing and painting on the walls and throwing waste material in the water and around the sea site) damage the coastal…

743

Abstract

Purpose

Tourists’ irresponsible behaviours (e.g. damaging flowers, writing and painting on the walls and throwing waste material in the water and around the sea site) damage the coastal environment. The irresponsible behaviour of tourists has raised concerns about the sustainability of the coastal tourism environment. The purpose of this study is to identify and explain the behavioural patterns of tourists that can influence the environmentally responsible behaviours (ERBs) of tourists, particularly in the context of coastal tourism. The study aims to provide a theoretical and practical explanation of destination image and perceived destination value (PDV) in shaping ERB with the mediating role of destination social responsibility (DSR) among tourists at the coastal touring destination.

Design/methodology/approach

The study used a quantitative research design and data were gathered from the five beaches in Karachi. Structured equation model was used to analyse the direct and mediating effect while stepwise regression was used to analyse the moderating effect of DSR. The results of the direct effect showed that cognitive image has a significant effect on the affective image, while the insignificant effect on conative image and ERB. While the affective image has a significant effect on conative and ERB, and finally, results showed a significant effect of conative image on ERB. Results of the study revealed that PDV significantly mediated the relationship between cognitive, affective and conative destination image and ERB. Finally, the study’s results revealed that DSR has significantly moderated the relationship between affective, conative destination image, PDV and ERB.

Findings

The results are divided into three categories, direct effect, mediating effect and moderating effect. The results of the direct effect showed that cognitive image has a significant effect on the affective image, while the insignificant effect on conative image and ERB. While affective image has a significant effect on conative and ERB, and finally, results showed a significant effect of conative image on ERB. It is found in the results that PDV significantly mediated the relationship between cognitive, affective and conative destination image and ERB. Finally, the study’s results revealed that DSR has significantly moderated the relationship between affective, conative destination image, PDV and ERB.

Research limitations/implications

First, data has been collected from a single geographic area of Pakistan. Therefore, cross-country data are required to compare the ERB of tourists. Second, only local respondents are considered in the study; future studies may include foreign tourists as well. Finally, data has been collected during one month in summer, which may have measured the experience of only summer. The respondent may have different perceived values and destination images during winter. The future study may split data collection into summer and winter to cover diverse perceptions of tourists.

Social implications

It is almost impossible for coastal destinations to achieve a competitive advantage without attaining sustainable coastal environments. Clean and green beaches and responsible behaviour towards marine mammals can only be achieved through tourists’ ERB. This study has major contributions towards society by reserving the natural environment of coastal areas.

Originality/value

This research will significantly contribute to the existing literature by extending the ERB knowledge through the theoretical lens of cognitive-affective-conative models and social expectancy theory. Moreover, PDV as a mediator and DSR as a moderator will enhance the understanding of ERB and extend the existing literature. Further research has provided a strong understanding of how cognitive, effective and conative image helps in influencing the ERB of tourists. Moreover, research will benefit destination managers and policymakers to enhance the image and perceived value of touring destinations. Finally, this study is a unique attempt to present a comprehensive model which could be applicable to diverse situations and areas.

Details

Social Responsibility Journal, vol. 19 no. 10
Type: Research Article
ISSN: 1747-1117

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