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Article
Publication date: 28 May 2020

Menglong Ding, Chuan Zeng and Wieslaw K. Binienda

Wingtip loss is an existing type of transport aircraft hazard which is a real threat to flight safety caused by a missile strike, underwing engine explosion or impact with…

175

Abstract

Purpose

Wingtip loss is an existing type of transport aircraft hazard which is a real threat to flight safety caused by a missile strike, underwing engine explosion or impact with obstructions when performing near-ground operations. The primary effect of the wingtip loss is an asymmetric rolling moment, which may result in the fatal loss of control for the aircraft. This study aims to assess whether aerodynamic degradation will cause a wing-damaged transport aircraft to lose its balance under a certain level of wing damage and if a pilot can compensate for the loss of aerodynamic force and regain the balance of the aircraft.

Design/methodology/approach

In this paper, experimental and numerical studies were conducted to investigate the aerodynamic characteristics of a wingtip-lost transport aircraft in landing configuration. Various levels of wing damages including wingtip, slat and flap loss were considered. The numerical simulations were performed with ANSYS Fluent. The computational fluid dynamics calculation was validated by wind tunnel tests.

Findings

The aerodynamic performance of the aircraft with wing-damaged condition was presented. It was revealed that the wingtip loss leads to an asymmetric rolling moment and a reduction of the lift force, which affects the balance of the transport aircraft. The methods to compensate for the lift force and the asymmetric rolling moment were investigated for a safe landing. The lateral balance cannot be maintained in cases with serious damage on the wing (larger than 53% of the semi-span) or moderate damage on the wing with loss of slats and flaps.

Originality/value

The nonlinear results indicate the importance of aerodynamic assessment for the sake of training pilots to properly handle the hazard situation and explore the critical facts leading to the air crash.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 7
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 20 June 2019

Wenqing Wu, Xin Ma, Yong Wang, Yuanyuan Zhang and Bo Zeng

The purpose of this paper is to develop a novel multivariate fractional grey model termed GM(a, n) based on the classical GM(1, n) model. The new model can provide accurate…

376

Abstract

Purpose

The purpose of this paper is to develop a novel multivariate fractional grey model termed GM(a, n) based on the classical GM(1, n) model. The new model can provide accurate prediction with more freedom, and enrich the content of grey theory.

Design/methodology/approach

The GM(α, n) model is systematically studied by using the grey modelling technique and the forward difference method. The optimal fractional order a is computed by the genetic algorithm. Meanwhile, a stochastic testing scheme is presented to verify the accuracy of the new GM(a, n) model.

Findings

The recursive expressions of the time response function and the restored values of the presented model are deduced. The GM(1, n), GM(a, 1) and GM(1, 1) models are special cases of the model. Computational results illustrate that the GM(a, n) model provides accurate prediction.

Research limitations/implications

The GM(a, n) model is used to predict China’s total energy consumption with the raw data from 2006 to 2016. The superiority of the GM(a, n) model is more freedom and better modelling by fractional derivative, which implies its high potential to be used in energy field.

Originality/value

It is the first time to investigate the multivariate fractional grey GM(α, n) model, apply it to study the effects of China’s economic growth and urbanization on energy consumption.

Details

Grey Systems: Theory and Application, vol. 9 no. 3
Type: Research Article
ISSN: 2043-9377

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Article
Publication date: 15 May 2019

Wenqing Wu, Xin Ma, Yuanyuan Zhang, Yong Wang and Xinxing Wu

The purpose of this paper is to study a fractional grey model FAGM(1,1,tα) based on the GM(1,1,tα) model and the fractional accumulated generating operation, and then predict the…

202

Abstract

Purpose

The purpose of this paper is to study a fractional grey model FAGM(1,1,tα) based on the GM(1,1,tα) model and the fractional accumulated generating operation, and then predict the national health expenditure, the government health expenditure and the out-of-pocket health expenditure of China.

Design/methodology/approach

The presented univariate grey model is systematically studied by using the grey modelling technique, the fractional accumulated generating operation and the trapezoid approximation formula of definite integral. The optimal system parameters r and α are evaluated by the particle swarm optimisation algorithm.

Findings

The expressions of the time response function and the restored values of this model are derived. The GM(1,1), NGM(1,1,k,c) and GM(1,1,tα) models are particular cases of the FAGM(1,1,tα) model with deterministic r and α. Compared with other forecasting models, the results of the FAGM(1,1,tα) model have higher precision.

Practical implications

The superiority of the new model has high potential to be used in the medicine and health fields and others. Results can provide a guideline for government decision making.

Originality/value

The univariate fractional grey model FAGM (1,1,tα) successfully studies the China’s health expenditure.

Details

Grey Systems: Theory and Application, vol. 9 no. 2
Type: Research Article
ISSN: 2043-9377

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Article
Publication date: 1 April 1997

Tser‐yieth Chen

Employs data envelopment analysis (DEA) to evaluate the relative performance of 23 university libraries in Taipei City and County. The estimated results show that 11 university…

21055

Abstract

Employs data envelopment analysis (DEA) to evaluate the relative performance of 23 university libraries in Taipei City and County. The estimated results show that 11 university libraries are relatively efficient. The results also show that nine out of these 11 have a relatively good academic research function. Only Ming‐chuan Management College and Shih‐chien Design College are attributed lower research capabilities. Marine and Oceanic University, Yang‐ming University and Ming‐chuan Management College are rated the top three libraries and enjoy the highest levels of efficiency in the sample. Shows that the resource utilization of these university libraries functions well. Finds that the inefficient libraries manage their acquisition expenditures and book circulation poorly.

Details

Asian Libraries, vol. 6 no. 1/2
Type: Research Article
ISSN: 1017-6748

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Article
Publication date: 1 August 2016

Xiao-feng Zhang, Xiao-juan Zhang, Lei Li, Gui-quan Li and You-min Xi

This study aims to focus on the authority formation process of Chinese enterprise leaders, with the purpose of finding out how an ordinary newly established firm leader develops…

348

Abstract

Purpose

This study aims to focus on the authority formation process of Chinese enterprise leaders, with the purpose of finding out how an ordinary newly established firm leader develops into a real top leader and achieves the status of legitimacy in a well-known enterprise.

Design/methodology/approach

Based on constructivist grounded theory, this paper investigates the formation mechanism of entrepreneurial authority in China by using the rich data of Liu Chuan-zhi’s leader activities.

Findings

In the “evolution” path of authority formation, leaders continually consolidate and improve their authority through two classes of exceptional management activities: “emergency rescue” and “promotion activities”. The successful realization of exceptional management activities benefits from a leader’s management experience accumulation and relationship maintenance with the government. In the “design” path of authority formation, leaders consolidate and improve their authority by exercising their position of power. Leaders’ legitimacy is reflected by making strategic decision and demonstrating discretion of position power. Additionally, passing on an inspiring leader’s thoughts and ideas to an organization’s members is accomplished through the construction of organization culture, institutionalization and convention.

Research limitations/implications

First, the findings are based on only Liu Chuan-zhi’s case. The authors still need more cases to compare and develop the findings and seek theoretical saturation in a broader sense. Second, the qualitative analysis is based on secondary data and future research could consider the introduction of interviews, video and other types of research data.

Originality/value

Under the parallel paths which are “evolution” and “design”, the dynamic leader authority formation model in China is founded.

Details

Nankai Business Review International, vol. 7 no. 3
Type: Research Article
ISSN: 2040-8749

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Book part
Publication date: 30 September 2020

Anam and M. Israrul Haque

The rapid increase in analytics is playing an essential role in enlarging various practices related to the health sector. Big Data Analytics (BDA) provides multiple tools to…

Abstract

The rapid increase in analytics is playing an essential role in enlarging various practices related to the health sector. Big Data Analytics (BDA) provides multiple tools to store, maintain, and analyze large sets of data provided by different systems of health. It is essential to manage and analyze these data to get meaningful information. Pharmaceutical companies are accumulating their data in the medical databases, whereas the payers are digitalizing the records of patients. Biomedical research generates a significant amount of data. There has been a continuous improvement in the health sector for past decades. They have become more advanced by recording the patient’s data on the Internet of Things devices, Electronic Health Records efficiently. BD is undoubtedly going to enhance the productivity and performance of organizations in various fields. Still, there are several challenges associated with BD, such as storing, capturing, and analyzing data, and their subsequent application to a practical health sector.

Details

Big Data Analytics and Intelligence: A Perspective for Health Care
Type: Book
ISBN: 978-1-83909-099-8

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Article
Publication date: 1 April 2005

Guoquan Chen

This paper aims to establish an organizational learning system model based on both western and Chinese management thoughts.

4343

Abstract

Purpose

This paper aims to establish an organizational learning system model based on both western and Chinese management thoughts.

Design/methodology/approach

The approach is a conceptual model which is based on research within the field.

Findings

The model consists of nine interrelated organizational learning sub‐systems including “discovering”, “innovating”, “selecting”, “executing”, “transferring”, “reflecting”, “acquiring knowledge from environment”, “contributing knowledge to environment”, and “building organizational memory” ones. The evidences in some famous Chinese traditional cultural classics (including Great Learning, Doctrine of the Mean, The Analects of Confucius, Book of Change, Tao‐Te‐Ching, The Art of War and Chuan‐Xi‐Lu) that support the rationale of the model are described and analyzed.

Originality/value

Several propositions are developed and it is hoped that the model is applicable in both eastern and western business environments.

Details

Management Decision, vol. 43 no. 4
Type: Research Article
ISSN: 0025-1747

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Article
Publication date: 3 October 2016

Hui-Wen Vivian Tang and Tzu-chin Rojoice Chou

The purpose of this paper is to evaluate the forecasting performance of grey prediction models on educational attainment vis-à-vis that of exponential smoothing combined with…

182

Abstract

Purpose

The purpose of this paper is to evaluate the forecasting performance of grey prediction models on educational attainment vis-à-vis that of exponential smoothing combined with multiple linear regression employed by the National Center for Education Statistics (NCES).

Design/methodology/approach

An out-of-sample forecasting experiment was carried out to compare the forecasting performances on educational attainments among GM(1,1), GM(1,1) rolling, FGM(1,1) derived from the grey system theory and exponential smoothing prediction combined with multivariate regression. The predictive power of each model was measured based on MAD, MAPE, RMSE and simple F-test of equal variance.

Findings

The forecasting efficiency evaluated by MAD, MAPE, RMSE and simple F-test of equal variance revealed that the GM(1,1) rolling model displays promise for use in forecasting educational attainment.

Research limitations/implications

Since the possible inadequacy of MAD, MAPE, RMSE and F-type test of equal variance was documented in the literature, further large-scale forecasting comparison studies may be done to test the prediction powers of grey prediction and its competing out-of-sample forecasts by other alternative measures of accuracy.

Practical implications

The findings of this study would be useful for NCES and professional forecasters who are expected to provide government authorities and education policy makers with accurate information for planning future policy directions and optimizing decision-making.

Originality/value

As a continuing effort to evaluate the forecasting efficiency of grey prediction models, the present study provided accumulated evidence for the predictive power of grey prediction on short-term forecasts of educational statistics.

Details

Kybernetes, vol. 45 no. 9
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 26 December 2024

Shih-Hao Lu, Huyen Thi Thanh Tran, Thanh-Sang Ngo and Chen-Hao Huang

Given the growing use of virtual reality (VR) technology in marketing, our research focuses on the development trajectory of research in the marketing field from 2012 to 2022 to…

26

Abstract

Purpose

Given the growing use of virtual reality (VR) technology in marketing, our research focuses on the development trajectory of research in the marketing field from 2012 to 2022 to identify essential phases and sub-trends within this topic.

Design/methodology/approach

This study employs a main path analysis (MPA) methodology to analyze academic articles related to VR in marketing from the Web of Science database.

Findings

The research on VR in marketing has experienced significant growth over the past 10 years and is projected to continue thriving in the future. During the past decade, research in this field has transitioned from exploring VR affordances in marketing to realizing the potential of VR in marketing. From the information systems perspective, the three primary research trends that have garnered the most attention from researchers are VR technology as an artifact, marketers’ motivational approach and consumers’ motivational approach. With the continual advancement of VR technology, the research trend of Metaverse marketing will gradually displace VR in marketing.

Originality/value

To the best of our knowledge, this is the first research using MPA to explore the development trajectory of VR in marketing and provide a comprehensive picture of it under the Affordance-Actualization theory.

Details

Online Information Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1468-4527

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Article
Publication date: 8 August 2022

Haiyue Fu, Shuchang Zhao and Chuan Liao

This paper aims to promote urban–rural synergy in carbon reduction and achieve the dual carbon goal, reconstruct the low-carbon urban–rural spatial pattern and explore planning…

639

Abstract

Purpose

This paper aims to promote urban–rural synergy in carbon reduction and achieve the dual carbon goal, reconstruct the low-carbon urban–rural spatial pattern and explore planning strategies for carbon mitigation in urban agglomerations.

Design/methodology/approach

The authors propose the idea of land governance zoning based on low-carbon scenario simulation, using the Beijing–Tianjin–Hebei (BTH) urban agglomeration as the empirical research area. Specifically, the authors analyze its spatiotemporal evolution characteristics of carbon balance over the past two decades and simulate the land use pattern under the scenario of low-carbon emission in 2030. Furthermore, the authors create spatial zoning rules combined with land use transition characteristics to classify the urban agglomeration into carbon sink restoration zone, carbon sink protection zone, carbon control development zone and carbon transition agriculture zone and put forward corresponding targeted governance principals.

Findings

The study findings classify the BTH urban agglomeration into carbon sink restoration zone, carbon sink protection zone, carbon control development zone and carbon transition agriculture zone, which account for 28.1%, 17.2%, 20.1% and 34.6% of the total area, respectively. The carbon sink restoration zone and carbon sink protection zone are mainly distributed in the northern and western parts and Bohai Rim region. The carbon transition agriculture zone and carbon control development zone are mainly distributed in the southeastern plain and Zhangjiakou.

Research limitations/implications

The authors suggest restoring and rebuilding ecosystems mainly in the northwest and east parts to increase the number of carbon sinks and the stability of the ecosystem. Besides, measures should be taken to promote collaborative emission reduction work between cities and optimize industrial and energy structures within cities such as Beijing, Langfang, Tianjin and Baoding. Furthermore, the authors recommend promoting sustainable intensification of agriculture and carefully balance between both economic development and ecological protection in Zhangjiakou and plain area.

Originality/value

The authors propose a zoning method based on the optimization of land use towards low-carbon development by combining “top-down” and “bottom-up” strategies and provide targeted governance suggestions for each region. This study provides policy implications to implement the regional low-carbon economic transition under the “double carbon” target in urban agglomerations in China.

Details

China Agricultural Economic Review, vol. 14 no. 4
Type: Research Article
ISSN: 1756-137X

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